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www.americanradiohistory.com November, 1916 THE ELECTRICAL. EXPERIMENTER

300 -PAGE ELECTRICAL DUCK'S BEGI.lo and WIRELESS CATALOG MORE THAN EVER JUSTIFIES YOUR VERDICT THAT IT IS THE ONE CATALOG WORTH WHILE

150 pp. Wireless In- stru ments. 150 pp. Electrical Sup- plies. Over 40 pp. of Wireless Instruments. 15,000 of our catalogs Only 8c. in stamps ready for delivery to will bring this unri- eager electrical and valled catalog to your home. The great cost wireless enthusiasts of catalog and the ex- in all parts of the ceptionally low prices (oftentimes fully 25% world, One of ten below usual retail price) consecutive ship- prohibits its distribution otherwise. You ments of catalogs to may deduct the 8c. on our patrons during first $1.00 purchase. last November. WHAT OUR BÌG CATALOG CONTAINS 150 pp. Wireless Instruments, magnet wire of all kinds, raw material, storage batteries, telegraph instruments, battery motors, commercial motors and gen. erators, sewing machine motors, telephones, step -down transformers. massage vibrators, bells, push buttons, auto accessories, flash lights, hand lanterns, auto and miniature lamps, Xmas tree outfits, voltmeters, ammeters, lighting plants, Victrolas, air rifles, electric aeroplanes, model builders, electric railways,electrical and mechanical books and general electrical supplies. ST, The William B. Duck Co., 230 TOLEDO, OH OR The Moorhead Tube Patent Pending

The MOORHEAD tube must not be confused with the two member valve, as it is inopera- tive without the outer electrode, or do not class it with the Trons or three member detectors as it is far more sensitive than either, in fact it is the most constant, stable and sensitive detector that has been developed. A wonderful feature of the Moorhead tube is the static elimination. On the nights when static make the reception of stations with the ordinary detector impossible, the Moorhead tube brings the signals in with a marvelous clearness. The initial cost of the Moorhead tube is low when the guaranteed long life is considered, and the fact that each Moorhead tube is a guaranteed DETECTOR, AMPLIFIER and OSCILLATOR SPECIAL INTRODUCTORY PRICE UNTIL JAN. 1, 1917 $ 6 .50 PREPAID AND DELIVERY a17 U GUARANTEED WE REPLACE ANY DEFECTIVE TUBES WITHOUT QUESTION Write for circulars on the MOOR HEAD tubes and Special sets Pacific Research Laboratories, Sole Manufacturers PACIFIC LABORATORIES SALES DEPARTMENT 534 Pacific Building SAN FRANCISCO, CALIF.

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www.americanradiohistory.com 466 THE ELECTRICAL EXPERIMENTER November, 1916

(EARN ELECTRICITY

::- WICKS ICKS tesson. Sson t$o 5 WICKS Lesson No. IS

\\ rite me at once-TODAY! Just send the coupon or a postal. I will give you 20 complete lessons in practical electricity FREE! Think of it ! My personal and individual instruction for 20 lessons without a cent of cost to you if you act quick. No charge to you for these 20 lessons now or later. I make this sensational offer to secure a few more live students-to show, too, how quickly I can make you a Master Electrician no matter where you live, or what you do. But you must act at once! This offer closes in 23 days I Remember these free lessons are not merely sample lessons, but are a regular part of my full and complete course in electricity. Send the coupon without delay- TOD.A1'I Earn X2,500 to X4,000 a Year You can now qualify at home during your spare time, and without giving up your present position or occupation, for that most wonderful of all fields open to the ambitious man -the great and growing field of Electricity! Yes, no matter if you don't know a thing about electricity or never had a bit of electrical experience, I will take you in hand and make you an Expert Electrician so that you should easily earn $2,500 to $4,000 a year and more. And I'll do it so quickly and with so little effort on your part, that you'll wonder how it was possible. No hooks or tools to buy. I Train You By Mail! Men Wanted A. W. WICKS, E. E. instruct you p r,unally the whole I will -make Wherever you go there's always urgent demand Formerly with the General matter so simple for you that you can't help but Electric Co.; former General learn. When you have finished my instructions for Expert Electricians and at big pay. That's Manager of company ,na,tu- of Jacturing Jenncy Electric Mo- you are an Expert Electrician -ready to take a because the watchword the age is, "DO IT tors; also formerly with Fair- big paying job or start in for yourself. I show ELECTRICALLY." The field of electricity is banks, Morse R Co.; now Con- not only how to do practical electrical work, you broadening so fast that there's a big shortage of sulting Engineer and Director but how to estimate on jobs so that you can take of the !licks Electrical Insti- competent electricians. And the demand is in- tute. contracts at big profits. That's what it means to be trained by a man of my practical experience. creasing every day.

Mail Coupon Today I YOU MUST ACT QUICK Mail coupon today. I want to hear from you immediately. Don't miss my offer of 20 personal lessons free. Remember this offer is strictly limited A. W. WICKS, E. E., Director, Wicks Electrical Institute to 23 days. Write for all particulars at once. Here's your chance! No 81 W. Randolph St. Dept. 226 Chicago, Ill. obligation to you. Send coupon or postal NOW! Without any obligation to me whatever, please send me full description of your personal instructions in Electricity and particulars of your I A. W. WICKS, E. E., Director special offer of 20 of your lessons free. I Name Wicks E lectrical Institute I 81 W. Randolph St., Dept. 226 Chicago, 111. Street and No City State You benefit by taentio,tng "Í be Electrical Experimenter" when writing to advertisers.

www.americanradiohistory.com he Ellectilicail Experimenter 233 Fulton Street, New York. Published by Experimenter Publishing Company, Inc. (H. Gernsback. President; S. Gernsback, Treasurer; M. Ilymes, Secretary), 233 Fulton Street, New York Vol. IV Whole No. 43 CONTENTS FOR NOVEMBER, 1916 No. 7

FRONT COVER-, "LIGHTNING MADE TO ORDER." UNCLE SAM'S NEW 40 -MILE AN -HOUR ELECTRIC BATTLE - From a painting by George Wall. CRUISER By_I1. Winfield Secor and Arthur C. Doyle. 478 WIRELESS AND AEROPLANES All) EUROPEAN "GUN DR. CHARLES P. STEINMETZ (Our Supplement feature) 481 SPOTTERS" 469 NEW ELECTRICAL METHOD OF CLEANING SILVERWAILE- HOW ELECTRIC CURRENT CONTROLS GREAT "MOVIE" A HELP TO MOTHER 482 BATTLE SCENES 470 THE SPERRY 1.280,000,000 C.P. SEARCHLIGHT THROWS BEAM ELECTRICITY IN THE TREATMENT OF INFANTILE OVER FIFTY MILES 484 PARALYSIS 471 TIIE MARVELS OF MODERN PHYSICS THE TELEPHONE VALUABLE IN TARGET PRACTICE 472 By Rogers D. Rusk B.Sc. 485 ELECTRIC DEVICES HELP THE HOUSEWIFE 473 BARON MÜNC1-IIIAUSEN'S NEW SCIENTIFIC ADVENT(JRES. LIGHTNING MADE TO ORDER By IIugo Gernsback. 486 By Samuel Cohen. 474 WHEN AMATEUR WIRELESS WAS YOUNG.... By H. de Scott. 488 MOVIE CONCERN BUILDS PORTABLE ELECTRIC PLANT 477 RADIO LEAGUE OF AMERICA 489

*1J111.410-1.JI0.110.1JI!1JLN11 if.t09-11VARILIIuIIPM14.4109 OR L!J Radium and Evolution L!J

1, we place a thermometer into a phial con- though this tunnel is far abo taining a minute quantity of Radium came unendurable 'as the work Bromide, it will indicate a temperature 2.7 cooling had to be resorted to in or - ow the degrees hotter than the temperature out- workmen to proceed with their work. Professor Joly side of the phial. then made the astounding discovery that the rocks of the Simplon contained Radium, which accounted for the What the température would be if we substituted Ra- unexpected high temperature within the mountain. dium for Radium Bromide, we have no means of knowing. For science has not as yet produced pure Radium, From this Joly has built up a new theory of evolu- P4) although the lay world prefers to think so. Our closest tion and while revolutionary in the extreme it is most approach to Radium so far has been Radium Bromide, plausible and gains more - adherents each year. which if .kure. consists roughly of three- fifths by weight of the element Radium and two -fifths of the element Lord Kelvin already deduced that if the earth contained only two of Radium per million million Bromine. . parts - and a great deal more is actually found in the rocks Turning back to our thermometer we also make the and crust of our globe -this minute quantity would discovery that the heat radiated from our speck of raise the temperature of the earth's core 1,800° C. in LJ Radium Bromide does not grow less as the days and one hundred million years. There being no escape for 11+J months, nay years and centuries, roll by. The mysteri- the imprisoned heat -the earth's cruet being an exceed- L!J ous element continues to furnish prodigious amounts of ingly bad heat conductor -Professor Joly convinces us 0.) energy, with never a let up, or at least not until it has that as the ages roll by, the interior of the earth must L_1 "worked" for 2,500 years -this being the present calcu- become hotter and hotter. Finally, after the end of L) lated age of Radium. millions of years, the crust must give way to this tre- L!J mendous heat from within and the bursting earth must L In order tobetter comprehend'what this means, let us go up in flames, becoming a burning gas ball, just as J compare it with coal. This is what we P.J find: we see our sun today. According to Professor Soddy, a gram of pure Ra- This will be the "incandescent age," a title suggested dium evolves 133 calories of heat per hour. In one by Professor Soddy. After another tens of million years year (8760 hours) the same gram of Radium evolves the incandescent earth will have expended all of its heat L!J 1,160,000 calories. In 2500 years -the length of time into space by radiation and it gradually will cool. A Radium will evolve energy -2,900,000,000 calories will be new crust then begins to form anew. This is what we developed. Now, one gram of coal when burned see at present on the planets Jupiter and Saturn, worlds evolves 2,200, net, calories of heat. Consequently, the just beginning to cool after emerging from their incan- energy developed by Radium is more than a million descent age. times that furnished from the combustion of coal. Thus we find that worlds do not die. They slowly Commercial Radium salts are at present obtained by pass from one stage to another, in a long and intermin- [kJ working the Austrian Pitchblende and lately from the able cycle. It is more than probable from the above American Cornotite found in Colorado. These are that the earth must have passed many times through L!J practically theonly commercial sources known today. this cycle. Probably every time the world went up in flames, man was at his highest point of civilization, in- But Radium is by no means as scarce as most people finitely further advanced than we are today. In an in- believe. Radium emanations have been found in springs, stant every living soul had perished and for millions of in the air, in rocks, etc., and this has given rise to an years hia like was not to tread again on the hardened extraordinary throry regarding .the evolution of the earth crust. worlds. This is the new and greater gospel of Radium, the L When the famous Swiss-Italian Simplon tunnel was element which will emancipate man and which will constructed some years ago, totally unforeseen circum- destroy him and his all later. stances arose which made the work most difficult. Al- H. GERNSBACK.

14J 1111111111111111111111111111111.114111 1111111J11111 + L!J!JL!J1JL1JL1JLJ MAP THE ELECTRICAL EXPERIMENTER is published on the 15th of each has been included. ALL accepted contributions are paid for on publication. A month at 233 Fulton Street, New York. There are 12 numbers per year. Sub- special rate is paid for novel experiments; good photographs accompanying them scription price is $1.50 a year in U. S. and possessions. Canada and foreign countries, are highly desirable. $2.00 a year. U. S. coin as well as U. 8. stamps accepted (no foreign coins or stamps). Single copies, 15 cents each. A sample copy will be sent gratis on request. Checks THE ELECTRICAL EXPERIMENTER. Monthly. Entered as second- and money orders should be drawn to order of THE EXPERIMENTER PUB- class matter at the New York Post Office, under Act of Congress of March 3, 1879. LISHING CO., INC. If you change your address notify us promptly, in order Title registered U. S. Patent Office. Copyright. 1910. by F. P. Co., Inc., New that copies are not miscamed or lost. A green wrapper indicates expiration. York. The contents of this magazine are copyrighted and must not be No copies sent after expiration. reproduced without giving full credit to the publication. All communications and contributions to this journal should be addressed THE ELECTRICAL EXPERIMENTER is for sale at all news stands in the to: Editor, THE ELECTRICAL EXPERIMENTER, 233 Fulton Street, New York. United States and Canada; also at' Brentano 's, 37 Avenue de l'Opera, Paris. West- Unaccepted contributions cannot be returned unless full return postage ern Advertising Office, 58 E. Washington St., Chicago. Ill. 467

www.americanradiohistory.com 468 THE ELECTRICAL EXPERIMENTER November, 1916

OUR NEW CATALOG X

of apparatus, "A little better than the best," displays in attractive form many improvements recently incorporated in a product already remarkable for its reliability during ten years of successful manufacture. We shall continue to give our customers prompt service, courteous treatment and apparatus which will be permanently serviceable. Catalog X of radio apparatus and general catalog of electrical apparatus and parts will be mailed upon request for which we ask the courtesy of 6c stamps to cover mailing both books. Type "A S A" Receiver A new receiving set of the most modern type. Wound with "Litzendraht" wire, primary dead end switch. Wave lengths - 400 to 15,000 meters, panel type, all ad- CLAPP EASTHAM CO. justments and connections on the front. 141 Main Street Mahogany case. br,ÿ4 Price $150.00 CAMBRIDGE - - MASS. 114; il^r t3441M4>41: 3 a WE ARE HEADQUARTERS FOR ELECTRICAL AND WIRELESS GOODS OUR NEW AMCO NAVY TYPE LOOSE COUPLER HAS MADE A TREMENDOUS HIT THE NEW AMCO NAVY TYPE LOOSE COUPLER embodies the most recent advances in the design of receiving transformers. High frequency resistance loss, capacity loss and leakage have been cut down by the use of special materials and methods. The primary winding is enclosed in a cabinet, the sides and top of which are polished black FORMICA giving a finish and having insulating qualities far superior to hard rubber. FORMICA is also unbreakable. Two 13 point switches on the front, control the primary by groups of several turns and by single turns respectively, thus giving a variation of from r to 156 PRICE $15.00 - -. -- turns in steps of one turn at a time. The secondary is wound with a special silk covered wire. The ends are polished FORMIC \. :\ very fine adjustment of the secondary is secured by a 12 point switch. This coupler is adapted to both short and long wave reception, and we guarantee it to be superior in every respect to any other coupler on the market or your money back. Order one of these Instruments today, keep It 10 days, and then II you don't like It send It back and we will refund your money by return mall OUR NEW BIG 232 PP. UNRIVALLED ELECTRICAL AND WIRELESS CATALOG IS THE EXPERIMENTER'S REFERENCE BOOK SEND 6 CENTS FOR OUR CATALOG. DO IT TODAY The latest edition of our famous catalogue is just off the press. Send 6 cents in stamps for a copy right away. It contains 232 pages and is fully illustrated. Complete description and prices of all the latest electrical. wireless and experimental apparatus, Storage Batteries, Rectifiers, Transformers, Spark Coils, Wire- less Apparatus. Lamps, Flashlights, Meters, Books, Tools, Dyna- mos, Motors, Railways, Wires, Supplies, Telegraphs, Telephones, Model Aeroplanes. etc. OUR PROMPT DELIVERIES WILL SAVE YOU TIME AND OUR PRICES WILL SAVE YOU MONEY This catalogue shows several hundred parts and sets of materials for building your Hare Is the Navy Junior own apparatus at home. We do all the Loose couplers in which the primary is variable by means of switches instead ofa difficult work in our factory and ypou can put the parts together slider have becomme so po ular that we bave brought out this wonderful little mstru- with to meet the demand at medium price, The erimur,' is fitted with a genuine the aid of a screwdriver and a pair of pliers. This cata- hartd rubber panel across the front, Two ten -point switehesare mounted on the pa 1. logue is worth more to you than all other catalogues put to- One switch controls the primary winding in groups of ten turns at a time while the other switch controls time. The primary therefore gether and you are doing yourself an injustice if you do not s neeturnn at a e y rotary ie nobsy and quickly send for it right away. the neeondare is variable by meona of a m lti- pointed switch, ton trolled by the same handle that vanes the coupling The aecondary is carried on two rods and slides with movement In and out of the primary. The _proportions of this tuner have been IF YOU ARE BUILDING SOMETHING WE HAVE JUST WHAT ,,,,,,,,., out by careful experiment and is ve efficient.lfi The instrument is beautifully easyryfinworkedished in dark mabegany, with gold lacquered brass trimmings, YOU HAVE BEEN LOOKING FOR PRICE ONLY $7.50 THESUPP ADAMS- MORCAN CO. YUINUUSEUS 13 Alvi n PL, Upper Montclair, N. J. WE ARE HEADQUARTERS FOR ELECTRICAL AND WIRELESS GOODS

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H. GERN 5 B AVK EDITOR H. W. 5ECDR A550CIIITE EDITOR

Vol. IV. Whole No. 43 NOVEMBER, 1916 Number 7 Wireless and Aeroplanes Aid European "Gun Spotters" WHILE it has been considered communication with the distant shell-spot- or Zeppelins at remarkable heights, it seems for a long time in military ting aeroplanes. The high -powered battle - that the French aviators have a way of circles that aeroplane wire- planes, each of which is equipped with a obtaining this most valuable information less was certain to prove ex- radio set capable of transmitting up to 30 without undue risk to themselves or their tremely valuable eventually, or 40 miles, sail forth, and though they machines. from all aspects, it is only within the past fly at a fairly great altitude, the aerial Undoubtedly the aviator may now and few months that we have heard anything observers are quite able to accurately ob- then lose his life, or at least be captured definite in this direction. serve the resultant effects of the shell fire. by the enemy, but by flying at a great alti- The Allies, according to reports received One of the reports states that a certain tude it seems he has been able to safely ob- from the battle- fronts, "somewhere in French battery of artillery actually suc- tain this much needed information and to France," have found a number of ingenious ceeded in dropping four shells in succes- signal it to the artillery officers, in a num- uses for the radio equipped aeroplane. One sion on a bridge 14 miles away. The offi- ber of casts which are on record.

The French Gun Batteries are Reported to be Planting Successive Salvos on Points 14 Miles Distant, with Machine -like Accuracy. An Aeroplane Fitted with Wireless Apparatus Flies over the Enemy's Position and Signals Back the Result of Each Shot. of these is to accurately locate (or "spot ") cers in the aeroplane helped to bring about It goes without saying that in any such and report the effect of shell firing over this truly marvelous accuracy of fire by case as here cited, where the range is as considerable distances, as clearly shown in signaling back the exact effect of the bom- great as fourteen miles, that those in charge the accompanying illustration. The manner bardment to the commanding officer be- of the guns cannot very well see the struc- in which this scheme operates in the in- hind the French lines, via radio. ture to be demolished from their position stance reported is as follows: While this scheme may seem hazardous except in rare instances. It often happens Behind the French lines there is erected in the extreme, especially where the enemy that such firing is to take place over a hill, a collapsible radio mast and the proper is plentifully supplied with modern anti- as shown in our illustration. Firing over signaling equipment capable of keeping up aircraft guns capable of hitting aeroplanes (Continued on page 5331

www.americanradiohistory.com I 470 THE ELECTRICAL EXPERIMENTER No%ember, 1916 How Electric Current Controls Great "Movie" Battle Scenes BEHI\D the staging of a trelnen- tion U.S. Army field guns, exactly timed to best way to use these lights without em- dous motion picture battle scene suit the psychological requirements of pro- ploying the mercury vapor tube lamps. The lie innumerable details of execu- ducer Blackton. These were not discharged studio experts utilize normal daylight as tive technical skill and in some of by the artillerymen that stood around the the blending medium. The satisfactory re- these electricity is depended upon guns. In this case the artillerymen merely sults from arcs can also be credited to an for essential results. An instance of this is went through the motions. A cool and exclusive improvement in mounting the in the work of the explosion man, as he is practiced man in the background fired them arcs, devised at this studio. The globe called by the Photo -play directors. To him with his trusty battery through wires con- supports are such that no shadow is thrown the use of a battery and wires and detona- nected to each gun. This was done in or- by the supports upon the field to be pho- tor is as important as to the engineer of der that the action of the guns would be ab- tographed. any colossal public work. The only dif- solutely timed with the action of the scene, Another improvement incorporated in ference is that the movie explosion man's and for that it was necessary that one man these lamps is the attachment of the rheostats effects are theatrical instead of practical. only have control of all the discharges. directly to the lamps. In studio work this In the recent film- is an item of great ing of a big battle convenience, since scene in Commodore ordinarily the rheostats are separate J. Stuart Blackton's The Two Upper Views Illustrate the "The Battle Cry of Staging of a Battle Scene for the 1 from the lamps and War" on Staten Film Play "1 he Battle Cry of War." installed on t h e A Mine Explosion Is Being Faith- walls wherein a Island, the explosion fully Duplicated in this Scene. bis maximum of wir- expert, with is involved little Below: One of the Few "Movie" ing to trusty detona- Studios Utilizing Arc Lamps for serve the outfit. tor, was a most im- Illumination. About one hundred portant factor in the of these arcs are spectacular success hung overhead in of the action. Her - the studio on ten m a n Rottjer, in tracks, spaced ten charge of explo- feet apart. They can sions for Vitagraph be moved about and films, staged burst- concentrated easily ing shells, gas at- anywhere, rheostats tacks and subterra- and all. The re- nean mines realis- mainder of the arcs tically with a touch are disposed of in of his finger on the form of twin - the arc floor lamps on electric key. Total- portable stands for ly inconspicuous on spots and ray effects, the side lines of the or in the form of battlefield, this ex- banks of six single pert executed explo- arc lamps mounted sions timed to the on frames that may fraction of the sec- be rolled from place ond, and without the to place to serve as injury of a single side lights. The person among the floor lamps and the hundreds that banks are fed with charged and strug- ,flexible insulated gled across the ter- cables, and since rain where scores of they carry their powder caches lay c own rheostats, a r e scattered. --. All this ^rn'F.P11* permissible for use was managed suc- tt\¡r iiñ.i._.+r.-K` at other locations cessfully, ending ..traslei+u._ uïtj where interior light with a climax of a for photography is mine explosion that required. consumed three hundred pounds of RHOTANIUM- t h e explosive at NEW SUBSTI- once. TUTE FOR Amid a charging PLATINUM. regiment small ex- One of the latest plosions that left scientific products shell craters three of Yankee genius is feet deep represent- an alloy known as ed the shattering of Rhotanium, intend- shells striking the ed to substitute ground. In connec- platinum. T h i s tion with these dis- composition is made charges bombs were up of several rare s i inultalieously metals including thrown into the air with a rapidity invisi- This was executed delicately and in perfect polonium. Its specific gravity is about one ble to the eye, exploding about 200 feet harmony with the plan of the producer, half that of platinum and its cost is 50% above ground simulating shrapnel explo- with varying pauses between each flash - less than platinum. The electrical resist- sions. Then, here and there, heavier erup- One- Three -Four -Two, by gun numbers. ance of Rhotanium is thirteen times the tions of earth gave the effect of mines. A remarkable use of arc light illumina- resistance of platinum, while the coefficient French mortars hurling bombs were also tion is that employed in the production of of resistance for changes in temperature imitated cleverly, while rolling clouds of gas motion pictures at the Vitagraph studio in is only one -third that of platinum. Due from nozzles in the defensive works gave a Brooklyn. In one of its glass -covered stu- to the relative low cost of this new alloy representation of the real thing in that line dios alone they employ 125 arc lights, all Here results it holds particular promise for use in the and there were mammoth 16 -inch so arranged as to give maximum crucibles and other chem- guns destroyed by internal explosions in photographically. manufacture of a manner to suggest that an enemy shell The matter for most comment in this ap- ist's ware for use in the chemical labora- had struck them fairly. plication of arc lights is the fact that they tory. It is expected to prove very desirable Another thing in which the indispensable are used alone and without any mercury for use as a resistance element in small electric detonating apparatus figured was tube lights as an adjunct. After long ex- electrical furnaces such as those used in the discharge of a battery of four regula- perimentation the company has found the laboratories, etc.

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 471 JAMES CLERK MAXWELL. November Marks His 37th Death Electricity in the Treatment of Infantile Paralysis Anniversary. The plague of infantile paralysis well - ratus, so that the physicians and nurses can Born, June 13, 1831. Died, Nov. 5, 1879. nigh succeeded in thoroughly alarming the at once obtain any certain form of current. James Clerk Maxwell was born at Edin- entire country during the past summer. Besides the direct application of electric boro, Scotland, June 13, 1831. His parents, Hundreds of new cases sprung up over- currents of certain wave form and voltage who were distinguished and well- to -do, night, as it were, and it seems to be the con- for the relief of muscular paralysis, there were amply able to afford him every world- sensus of expert opinion that once the are also available a number of special de- ly advantage. germs have started in their deadly work vices. There are motor -driven manipulat- His chief characteristic, as a boy, was that he showed the most lively curiosity in almost everything that came to his notice. His bent was for securing accurate knowledge, and when any indefinite reply was given him, he would at once come back with, "But what's the particular go of it ?" He was also a clever and indus- trious amateur experimenter, putting his questions directly to nature. Studious and well- trained in the fine schools of the Scottish capital, young Max- well early showed his proficiency in mathematics, making his first original contribu- tion to that science at fifteen; for, in 1846, while he was still at the Edinboro Academy, the principal, Professor Forbes, read a paper before the Royal Society on A Mechan- ical Method of Tracing Oval Curves, written by his youthful pupil. Shortly afterwards he entered the university, where he became an excellent student in mathematics and physical science. During this period he contributed several valuable papers. He graduated at the age of nineteen. As he was fond of science, he entered the Trinity College, Cambridge, where he took his doctor's degree in 1854. The following year he started on a series of electrical and magnetic studies, which became the leading work of his life. Maxwell's great work in electrical and magnetic philosophy consisted in gathering the vast store of experimental facts and observation on these subjects that had been Photo Copyright by International Film Senlee accumulating so rapidly during the past Electricity Has Helped to Alleviate the Suffering of the Thousands of Children Stricken with "Infantile hundred years, and weaving them into a Paralysis" and Here We See a Little Miss Receiving Such Treatment. workable theory, mathematically demonstrable, by means of which much of the very little can be done towards alleviating ing machines to which the patient's feet are observed phenomena could be explained and the suffering of the unfortunate victim. strapped, and while they sit in a chair in the relation between them better under- Some measure of success has been effect- front of the machine the apparatus works stood. ed by spinal injections of blood taken from the limbs back and forth. In many cases In this way he was able to go far be- persons who have previously had the dis- there is permanent relief from what promises to be a serious case of muscular para'. ease. However, there has to be a vast lysis. amount of muscular manipulation adminis- Professor Finsen, of the Finsen Univer- tered to those afflicted with the disease, and sity, has successfully demonstrated that the a great deal of good has been undeniably ultra -violet light, produced by his arc light, accomplished by this method of treatment. which is of special construction, has the ef- Artificial stimulation of the muscles and fect of curing infantile paralysis. It has nerves has been carried out in a number of also been shown that, by employing sunlight instances at some of the leading hospitals which passes through cobalt glass in such a by means of electric currents of the proper manner that it is applied directly,over the kind. The photograph shown herewith il- point where the paralysis is most acute, lustrates how electric current is applied to good results may be obtained in many in- a child suffering from the infantile paraly- stances. sis, the current being here applied through It is hoped that in the near future our two dampened sponge electrodes. Various American physicians will start a thorough strengths of Galvanic, Faradic and sinusoi- investigation with regard to the use of ul- dal currents are available from the elabo- tra- violet light for the curing of this per- rate switchboards shown in the background. plexing ailment so little understood at pres- These switchboards contain the necessary ent, both with respect to its causation, ger- electrical measuring and controlling appa- mination and cure. verified, while the developments of later possible to account for all electric and mag- years have profoundly changed our ideas netic action by supposing electricity and on some of the subjects Maxwell treated magnetism to be stresses and motions in a upon. weightless material substance, called the Perhaps the most famous instance of the ether. As a consequence of this he showed wonderful insight possessed by this investi- that the ratio of the two centimeter -gram- gator is the case of invisible electromag- second systems of electrostatic and electro -. netic waves. It was Maxwell who first de- magnetic units are numerically equal to the James Clerk Maxwell, the Famous Scotch Phy- sicist, monstrated that these effects travel through velocity of light in free space, expressed in upon Whose Mathematical Presumptions in Hertz and Others Have Built the Radio Telegraph space the form of transverse vibrations, centimeters per second, i.e., 30,000,000,000 of To-day. similar to those of light, but of much great- cms., or 186,000 miles per second. er wave length and at the same velocity This achievement has well been called yond the experimenters' past performances, of light. Faraday had guessed this and "the first great step towards the true un- for he was able to make predictions based Hertz proved by experiment that Maxwell's derstanding of the nature of electricity on his theory and its consequences -that conclusions were correct. The whole sci- and magnetism." certain things, when improved, would be ence of radio -telegraphy and telephony has All his activity of the first order took found in nature to be so. Since then many sprung from these basic and far -reaching place in the compass of a short life. He of his predictions have been experimentally facts. His grand conception was that it is (Continued on page 537)

www.americanradiohistory.com ins 472 THE ELECTRICAL EXPERIMENTER November, 1916 The Telephone Valuable in Target Practice THE telephone is doubtless the one to fire at. A man is detailed and stationed target that is above the pit and. being shot instrument which performs more at the telephone box with a telephone hand- at. This target is in turn pulled down in useful things than any other elec- set plugged in. After firing, any one of the answer to a buzzer signal and marked as in trical device. It is now used in men may call to the man at the telephone the first case. This alternating of targets target practice and it has been to sash or mark targets Nos. 2, 4, 10, etc. is continued with every shot and carried on found to be the most sat- at each of the other isfactory means ever targets in the same tried for signaling in manner. this kind of work. Sometimes it hap- In the target pits are a pens that the marking number of iron frames, is not properly under- each equipped with two stood, or there has movable sashes, as indi- been an error in the cated in Fig. 1. In location of the shot. the sashes are The range officer will placed iron buzzer then instruct the op- boxes equipped erator at the tele- wit h buzzers phone to call the offi- and terminal cer in the target pit strips. Midway a n d instruct in the pit, or at him to have about the cen- certain targets tral position of re- marked, o r all the targets, to have a n y is placed a tele- other informa- phone box. This tion that may box is equipped be desired with a bell that c o m municated i can be operated over the tele- from any of the phone. The of- firing lines, two ficer at the tele- jacks for plug- phone box on ging i n hand the firing line sets, and six push buttons. gets in touch immediately The push buttons are for ring- with the officer in the pit, to ing the bells mounted in the whom he gives instructions telephone boxes that are loca- using the hand set described. ted at different firing lines. When the officer in the pit de- These firing lines are usually sires to talk to someone on the planned at 200 to 1,000 yards range he pushes the button con- from the targets; Fig. 2 shows nected to the station desired. a squad firing from the 200 The operator at that point an- yard line. At each of these fir- swers the call and procures the ing lines there is located a sub- person wanted or delivers the stantial cast iron telephone box. message. Each box is fitted with a bell In some cases where the fir- that is operated from the tele- ing lines have quite a number phone station located in the pit, of targets say fifteen or twen- two jacks for connecting a ty, it is found difficult to call composite hand set, a push but- out to the man stationed at the ton to ring a bell at the sta- telephone the number of the tion in the pit, and a number target to be signaled. When of similar push buttons for op- this is the case, plugs are in- erating the buzzers that are inserted in jacks with their sig- stalled in front of each of the Militia Using the Telephone for Checking Target Scores at Augusta, Ga. f- nal conductor running out to targets in the pit. The Target l' its; 2- Officer and Telephone Operator at Firing Line 3-A the man on the firing line. One a company Closer View o f the Firing Line Telephone Operator Communicating with the of these is in When or squad of Target illustrated Fig. men are on any of the firing Checkers. 3. These men can then do their lines for practice shooting or own signaling by touching the contesting for record marks, an offi- The man at the telephone will push the cor- end of the conductor to an iron rod driven cer is stationed in the rifle pit at the responding number of buttons on the target into the ground. This feature is shown by telephone station to communicate with the called; the man in the pit hearing the buz- the cords from the telephone box to a pro- firing line. At each of the targets with its zer immediately pulls down the sash with tecting cover on the ground. When not associate buzzer is stationed an attendant target and locates the shots. As one tar- in use these conductors are coiled up and put to answer the buzzer signals, checking the get is pulled down the one in the other away with the hand set. This interesting targets and registering the position of the sash automatically goes up, so that one tar- equipment was installed for the Georgia shots fired at the target. get always appears above the pit. The re- State Militia at Augusta, Georgia, by the On the firing line the contestants for sult of the firing is signaled to the scoring Western Electric Company. markmànship are assigned to their respect- officer and the men on the firing line by Every day sees some new application of ive places in line with the targets they are holding a disc over a like position on the the telephone to the wants of mankind. STATUE TO PROFESSOR American industries. And now it is be- tution of German Electrical Engineers, the JOSEPH HENRY. ginning to seriously affect the telephone Institution of German Engineers, the In- A bronze statue to Professor Joseph business. stitution of German Architects, the Asso- Henry, whose name is intimately associated The pair of jumper wires used on the ciation of Blast Furnacemen, the German with the invention of the telegraph, is to main frame formerly consisted of one Chemical Society, and the Association of be erected' at Albany, N.Y., for which pur- white and one red cord. But in future Shipbuilding Engineers. Headquarters are pose funds are now being collected. they will consist of one white cord and an- in Berlin. The "Verband" will thus repre- Among the members of the honorary com- other white one with a couple of red sent 60,000 members of the different pro- mittee are Dr. Alexander Graham Bell, threads woven through it. fessions involved. One of the principal Theodore N. Vail. Thomas A. Edison, Dr. results which is looked for from the com- M. I. Pupin and Dr. J. J. Carty. UNION OF GERMAN TECHNICAL bination is the furtherance of the work of ASSOCIATION. finding substitutes for the raw material A "Verband" of the principal German hitherto obtained in neutral countries or TELEPHONE CORDS TO BE technical associations has been formed those with whom Germany is now at war. WHITE. under the name of the Association of Ger- What a fine chance for a "successful" al- The shortage of dyes, due to the Euro- man Scientific Societies. Those societies chemist, who could turn lead into copper, pean war, has been felt in. practically all comprising the "Verband" are the Insti- and silver into gold.

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 473 New Electric Devices Help the Housewife the latest attempt to retain oven, owing to the more flexible applica- with an embarrassment of riches where POSSIBLYthe labor -saving advantages of elec- tion of the heat and the fact that the electric appliances are concerned, and one tric cooking on a large scale, and at oven is entirely enclosed except for a great difficulty lies in deciding where to the same time to reduce its cost, may be small ventilating pipe. begin. 'l'he best plan is for the pros- seen in thc combination gas -electric range. The portable electric serving table mount- pective purchaser to study her own situ- This interesting novelty is equipped with a ed on wheels has come into vogue of late. ation and discover where its weakest spot "fireless- electric" oven while gas is retained One of these is shown herewith. They may lies. Undoubtedly she will find some ma- for the burners at the top of the stove. It contain several necessary devices such as chine designed to overcome that particular is too soon to speak authoritatively of the an electrically heated chafing dish, a cof- difficulty. And that is the point at which merits of this device. Certainly, however, fee percolator, tea -pot, a dish warmer, a she should begin thc electrification of her it promises well. stew-pan, etc. A flexible attachment cord housekeeping. Photos courtesy New York The electric range has come to stay. enables the hostess to connect the serving Edison Company. When properly used they not only repre- table to a convenient base or floor plug re- sent the acme of flexibility and cleanliness ceptacle. WIRELESS FROM GIRL IN CALI- but economy as well. Some of the ranges Then, too, the up-to-date electric housc- FORNIA HEARD IN LYNN, MASS. are equipped with automatic time- switches kceper can invoke the aid of the genie, Elec- The message, "l- Tello, Massachusetts; how which cut off the current at the end of tricity, to whip the cream, shave the ice, are you ?" vibrating its way across the coun- any desired prearranged time. In this way mix the cake or bread dough, sift the flour, try from San Raphael, Cal., was picked up the mistress or cook may start a roast on beat the eggs, chop meat, slice potatoes by Gustave A. F. Werner with his wireless the electric range and, having set the time - or fruit, polish the silver, wash the dishes, receiver in the Highland first station, Lynn, switch for the proper time period, she may et cetcra. Just snap the switch and - recently. go out and do her shopping. The roast will Presto -the magic current starts to work. The message was sent by Miss Kathleen be done to a turn when she returns. Unlike the human servant, it never becomes G. Parkin, fifteen years old, one of the Also it is possible to set the thermostat tired. It is satisfaction itself. youngest girl wireless operators in the to constantly maintain the proper tempera- Of electric refrigeration for household country. She signed the query and added ture. Baking, roasting and boiling can be purposes, one can now say that it is a fact. her address. done in this way. When the proper tent Machines to accomplish this work are now \Verner immediately replied, "First rate, perature is reached, which requires ten min- being produced, and it is said that the man- thank you." utes to half an hour, depending upon the ufacturers are still busy supplying the ad- She is a member of the American Radio temperature required, the current automat- vance orders for their machine. Like oth- Relay League, to which organization Wern- ically cuts off and from then on cooking er electric power devices, the arguments er also belongs. Miss Parkin and her work proceeds as in a fireless cooker. The heavy heat insulation about the Photo at Right (top) Shows one of Latest House- hold Conveniences-a Portable Electric Serving walls of the oven -two Table on Which There is a Percolator and Table inches of rock wool - Stove. A Flexible Cord and Plug Connects the Serv- causes the ovens to re- ing Table with the Nearest Base Receptacle. tain their heat for hours. Lower Right Hand View illustrates a Very Complete Elec- tric Kitchen with the Magic Current Performing All the No attention is required Work from Broiling a Steak to Washing the Dishes. until the hour arrives at Even the Refrigerator Ice Is Electrically Produced. which it was determined Photo Below Shows New Electric Range Equipped With the meal should be Time-clock Attachment and Thermostats to Maintain Even Heat and also to Cut off the Current at any Pre. ready. determined Time. With the new electric range, breakfast can be prepared in the way just mentioned the night before with the assur- ance that it will be ready exactly on time. Cooking processes that do not require much time and for which the food can be prepared in advance are performed oli the stove top. For this purpose the electric range has two 8-inch and one 10 -inch radiant heaters, each with a special three -heat indicating control switch. In the combination gas and electric ranges, the stove top is provided with four gas burners, one of which is of extra large size with a small, specially controlled sim- mering burner in the center. All the burners can be lighted instantly by means of an automatic gas lighter controlled by a valve at the front of the stove, which normally burns a very small pilot flame. It is claimed that better cooking results can be obtained in the for it include cleanliness, convenience and were described in the last issue of this electric ovens than in a gas oven, owing low operating cost. As a medium of re- journal. to the fact that two heaters are provided, frigeration it possesses two special advan- one at the top and the other at the bottom tages, the extremely small temperature va- An with electric apparatus for washing smoke baffle plates to provide a uniform riation, impossible to secure with melting has been perfected to relieve cities of the distribution of heat. Pastry can be ice, and the fact that the machine also pro- smoke nuisance. The smoke is driven by browned just as in any other kind of duces ample ice for table use, about twenty fans through a column of water which range. It is also claimed that food shrinks pounds in the course of twenty -four hours. washes out the soot and cinders. Pitts- less in these electric ovens than in a gas Indeed the modern housewife is faced burgh papers please copy! .

www.americanradiohistory.com 474 THE ELECTRICAL EXPERIMENTER NONCnil,er, 1916 Lightning Made to Order By Samuel Cohen ONE of the most perplexing prcU- that scientists have attacked during recent years involved either the harnessing or imitation of the forces of Nature. Many of our greatest scientists in all parts of the globe have spent fabulous sums and years of patient study on such problems, but most of them have signally failed; a number of eminent scientists even claim that such co- nundrums will never be thoroughly solved. This, however, appears, in our present day, to be highly doubtful. As early as 1890 Dr. Nikola Tesla undertook to solve the problem, and some years later succeeded in demonstrating to the world that it is quite possible to imitate certain natural dynamic forces on a scale of surprisingly vast magnitude. Most of us know that Lightning is a natural electrical tischarge taking place between two adjacent clouds, each having been charged with electricity of opposite polarity. As soon as they approach sufficiently close, the electric potential between them becomes so terrific that the air strata between is ruptured, thus producing a vivid spark, followed by thunder, which is caused by the sudden rush of air into the evacu- ated space produced by the electric discharge. Lightning may be caused also by a discharge taking place between a cloud and the earth. The process by which the clouds are electrically charged is still a mystery, and we must wait until some fu- Fig. I. The Wonderful Tesla, 300 K.W. High-Frequency Oscillator Coil in Full Activity, Discharging ture genius will explain to us the exact Sparks Like Veritable Bolts of Thor and Measuring 65 F.et Across. phenomena that takes place in the upper atmosphere, where such electrical disturbances take place. Dr. Nikola Tesla, who is perhaps the greatest living authority on alternating currents of both high and low frequency, has performed some of the most marvelous experiments ever dreamed of with high potential, high frequency currents. As early as 1890 this savant had produced electrical disturbances in his laboratory at Colorado Springs equal to the lightning produced by Nature. Although a number of years have elapsed since these experiments were conducted, not a single scientist or engineer has been able to produce such awe- inspir- ing, electrical performances as did Dr. Tes- la. It is true that he is far ahead of his time in many of his inventions, yet he has ably demonstrated that it is possible to imitate some of Nature's secret forces. It should be noted that his sole purpose was not simply to imitate these forces, but he was performing certain experiments on the problem of radio transmission of electrical energy through space. The startling lightning effects here shown were produced during the course of these experiments. During a recent interview the writer had with Dr. Tesla, the photographs herewith reproduced were kindly loaned to accompany this article. Two of these photos were never shown to the public before. Our front cover, painted by Mr. George Wall, is an exact reproduction in colors corresponding to Fig. 1. The man was seated near the apparatus solely for the purpose of showing the relative size of the high frequency oscillation coil. The photograph was obtained by double exposure; that is, the plate was exposed with the man, while the apparatus was not in operation; then he was removed and another exposure made of the sparks on the same plate, as it would not be very healthy for anyone to be there when the experiment is conducted. In Fig. 1 we see the Tesla electric oscillator in full activity at twelve million Fig. 2. A Close View of the Tesla Coil and Massive 'Metal Ball Which Acts as a Reservoir for the Electric Charges. (Continued on page 533)

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 47;

Pig. 3. Compare the Size of the Tesla Coils Here Shown with That of the Man at the Left. A Double Exposure Was Necessary -First with the Man and Apparatus, Then with the Apparatus (Less the Man) Fully Excited. Sparks Measure 22 Feet in Length. Fig. 4. A Problem in Harmonics. Dr. Tesla Placed a Number' of Inductance (Air Core) Coils Within the Large High Frequency Coil as Shown. Each Coil Resonated or Became Attuned to a Certain harmonic of the Fundamental Oscillation. Glowing as Seen.

www.americanradiohistory.com 476 THE ELECTRICAL EXPERIMENTER November, 1916

after breakfast. The inventor is in his six- Remarkable Electric illumination of Outdoor Theatrical ty -ninth year and still going strong. The illumination and lighting effects of scenic effects, invisible illumination for the the mammoth outdoor pageant Caliban, a musicians located over the stage and the THE OLDEST "HELLO" GIRL. Shakespearean Masque, produced light screening cutting out of At the Linkville exchange, just outside recently or the stage of Kansas City, Harry Moore, in the stadium of the College of the City from the view of the audience, during the aged 72 years, and his wife, Anna Moore, aged 66, of New York, were remarkable in being the arrival. plug most elaborate of ever wit- In spite of in on the switchboard to answer calls system lighting the extremely large areas to and give connections. They give day and be flooded with light, now night service bricht sunlight, and love the work. Though and then Mr. and Mrs. Moore are well along in shading off into different years, subscribers never have to complain colors and cutting out about the lines being busy, for their serv- portions of the scene en- ice is always prompt and cheerful. tirely, was accomplished These operators know every man, woman to the wonder of the spec- and child in their community, and they tators. know every subscriber's number. One of All the illumination and them is always at the switchboard. The lighting effects being pro- story of these oldest operators in the world, duced by incandescent who never receive a complaint on the serv- nitrogen -filled lamps, the ice, might be read with profit by the young- lighting was controlled est operators in the world. from a single switchboard Mrs. Moore knits and darns at the back of the stage, the switchboard. Her spectacles rest on the stage manager communi- lower ridge of her nose. Her gray hair is cating his orders to the done up tight on her head. She is the chief distant light operators and operator and her husband is her worthy Fig. I. Flood Illumination of the Huge Central Ring at Mammoth ordering color changes and faithful assistant. Outdoor Theatrical. The Distance from the Nearest Flood Light Projector to Center of the Ring Was Over 200 Feet. by means of an elaborate telephone system. So per- WOODPECKERS ATTACK nessed in a dramatic performance in Amer- fect was the central control that the lights ELECTRIC LIGHT POLES. ica. It marks special interest in the re- glowed mysteriously here and there during Certain kinds of birds are fond of bor- placing and proof of superiority of the the performance -the color of illumina- ing or pecking holes in trees and poles. A high power nitrogen -filled incandescent tion varying according to the scene. redwood pole on the Hanford line of the lamp projector over the arc lamp. The light for the general flood illumina- The magnitude of the lighting problem tion came from five sources of special light is appreciated when the immense outdoor towers. Fig. 2 shows one of the daylight areas to be flooded from great distances is flood reflectors, batteries of which were lo- considered. The circular stadium has a cated on the arcade of the stadium, high seating capacity of 20,000. The immense above the audience, the distance from these stage shown in Fig. 1, is 80 feet long, 40 lights to the center of the ring being some- feet high and 20 feet deep, and at a dis- thing over 200 feet. These flood reflectors, tance of over 300 feet from the spot and especially designed for this production, con- searchlight tower. At the height of the tained 1,000 watt nitrogen -filled incandes- illumination incandescent lamps and projec- cent lamps with high -power reflectors and tors drew 1,100 amperes from the alternat- a special light shield to conceal the source ing current lines, while searchlights and of light from the audience opposite. Two arc -lamp spot lights drew 30 amperes from banks of these lamps furnished general il- the direct current power station of the lumination for arrival and departure of the City College. audience front the grounds and during the The action performance the full battery was used for passed through flooding the central ring, and vari- colored three stages. In effects were secured by a boomerang or the large 100- quick -change color slides. A bank of these foot diameter lights concealed on either side of the stage ring in the cen- flooded the stage towers with blue light. ter of the sta- Two 18 -inch searchlights and three 50 am- dium, 1,500 pere spot lights, practically the only arcs trained amateur used in the production, served only for spot actors and ath- illumination of principal figures and in- dividuals. ,, - letes presented, in action, ritual One of the newest and most novel light- and dance, the ing features was the curtain of light. Dur- art of the the- ing the arrival and seating of the audience, The Woodpecker Is a Busy Bird. If You Don't Egypt, several 1,000 -watt, glass-lined reflectors Think So. Just See How He Decorated This ater in Electric Pole with His Bill. Greece, R o in e, were placed before the stage settings. Ger- These reflectors directed toward the au- France, San Joaquin Light & Power many. Spain and dience produced a mild blinding in the di- Company in rection of the stage, thus acting as a com- southern California recently had to be re- Elizabethan Eng- placed because of the activity of the birds land. Directly in plete screen or curtain of light. Special lighting for the musicians above in using it as a storehouse for winter food. front of the the stage and the chorus of 300 singers was The accompanying illustration shows a stage proper was accomplished by thirty, eight foot strips of section of the pole which contained many a large, dragon - blue lights, without interfering with the il- hundreds of acorns. This particular pole like form of lumination of the general performance. had been in service seventeen years. The cave, around The lighting effects and special lamps for base had been oiled but the part above which much of this production were designed, installed and ground was untreated. It should be ex- the action cen- engineered by the Universal Electric Stage plained in connection with this that only tered and which Lighting Co., of New York City. poles of soft wood, which have long been Fig. 2. One of the Day - was finally re- exposed to the weather, are attacked in this light Flood Reflectors, moved or seem- EDISON IN BED THREE HOURS way, and then only rarely to an extent that Fitted with 1000 Watt, ingly transferred makes Nitrogen Filled, Incand- IN 15 DAYS. trouble for the power companies. escent Lamp, Focusing by lighting ef- Thomas A. Edison recently went on an- By far the greater portion of the damage Device and Boomerang fects into a the- other "spree." His is a sleepless spree and s done by woodpeckers, although several or Colored Slide Holder. ater represented the one in question was termed by mem- other kinds of birds, native to California, by the stage bers of his "insomnia squad" in the in- ometimes attack wooden poles. In Mexico proper. The lighting consisted of general ventive wizard's laboratories, as one of and other countries it has become impera- illumination during the entrance and seat- the greatest he ever ventured forth on. tive that steel poles be employed, owing ing of the audience. White flood lighting During fifteen days Mr. Edison worked all to the fact that worms and other pests and vari- colored flooding of the different night. The fatigue of all night labor was persist in drilling holes in and through settings, illumination of the stage, with offset by an hour's sleep each morning them.

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 477 ELECTRICALLY MADE THUNDER- Movie Concern Builds Portable Electric Plant STORMS FOR THE "MOVIES." ONE more unit has been added to the stripped chassis of which was the foun- We sit at a 'movie" watching our fav- the great fleet of motor -cars in dation for the vehicle. The propulsion orite actor or actress performing all kinds the extensive garage of the Vita - motor is a White gas motor bought with of didoes, from jumping off a cliff to be- graph Company. This time it is the chassis. In the body as built are two ing electrocuted in the electric chair not a dynamo car to provide a port- separate compartments. In the front one, thinking perhaps that electricity plays able lighting system for motion- picture pho- which is the smaller, is a dynamo of 218 many hundred secret roles every day at the motion picture studios, from creating a beautiful tropical sun -set to an entranc- ing moonlight scene. It is up to the stage electrician to solve many of these problems, some of which could hardly be arranged for at all, if it were not for the great flexibility with which the electric current in its many forms, readily adapts itself to a hundred and one new problems Fig. 1 (top) shows the stage set for a thunder -storm scene from the Thanhouser- Pathé photo -play- Saint, !Woman and Devil- featuring Miss Florence La Badie. The rain is falling heavily as created by allowing water to fall in a thin sheet or curtain from the tank above the setting. Fig. 2 (bottom) shows the rain storm in full swing. The propeller at the right is driven by the electric motor seen at the center of the stage, and while rapidly revolving, the stage hands above the propeller empty several sprinkling cans of water on it. This results in a driving rain being blown against the rain curtain For Photographing Night Scenes in Isolated Districts One of the Leading Movie Producers Designed already falling. The actors do not get This Portable Gasoline Engine and Dynamo Plant. wet as they stand behind the falling sheet of aqua pura. The photos show the set- tography. The car, one of huge propor- amperes and 120 volts rating. The rear tings only. tions and large capacity, was built in the compartment contains a five- cylinder, ma- An electrically ignited flash -powder company's own garage from designs made rine gasoline engine of 50 H.P. at the charge, carefully manipulated, is passed by its experts. It is now in successful rather high speed of 750 revolutions per across the scene at the proper moment, operation. minute under load. The entire body is apparently shattering the large vase. The Such a car has long been needed, because lined with galvanized iron for fire proofing vase is sure to be shattered -never fear - and heavy rubber mats on the floor serve for the reason that it is secured to a at many outdoor locations in the more re- held by a nearby mote Long for electrical insulation. The body can be string stage attachee, sections of Island, where it is closed entirely to the weather. who cheerfully yanks it asunder at the desired to take motion -pictures at night, The studio arcs used for taking filin ac- psychological moment. there is no nearby electric line that may be tion indoors are of various sizes, tapped for current to supply the powerful consuming usually about 28 am- arc lights. The need for facilities became peres and 12 -15 amperes. The more urgent after the great production of dynamo on the car not only de- "The Battle Cry of War" was begun, se- veloped a full capacity for such quel to "The Battle Cry of Peace." lamps in the outdoor work but The dynamo car consists of an enclosed produced a highly satisfactory van -like body mounted on a 5 -ton truck, quality of light. TUNGSTEN PRODUCTION SETS ELECTRICITY IN THE NEW RECORD FOR THE LAUNDRY. UNITED STATES. The use of electricity in the The tungsten production of the United laundry has been making steady States during the first six months of 1916 progress, but its usual applica- exceeded the production of this or any tion is in driving motors and other country in any previous twelve heating irons and mangles. The months. Prices were even more phenom- extension of its use for elec- enal than production and reached more trolysis represents one of the than ten times their ordinary level. The latest applications which prom- output was equivalent to about 3,290 short ises to improve the laundering tons of concentrates carrying 60 per cent process, reduce the cost, and WO., valued at $9,113,000, according to an add to the load of the central estimate made by Frank L. Hess, of the station. There should be many United States Geographical Survey. Cali- opportunities for introducing fornia is one of the chief tungsten produc- this process in all cities. ing states. A notable application of this process on the British hospital SILVER CAN BE MAGNETISED. ship Aquitania has recently been By H. J. Gray. reported. In that case ordinary It was discovered in the course of some sea water is used as an electro- experiments conducted upon the Newtonian lyte and the resulting product is constant of gravitation, described in a paper applied not only in the laundry, read before the Royal Society in December, but also in the swimming bath, 1915, that silver is capable of being mag- for various disinfecting pur- netized under certain circumstances. Bars poses about the ship and for of very pure silver were heated to 130° C. surgical use. It is also applied and kept in a strong magnetic field, and it for the purification of drinking was afterward found that they had become water, one part in one million permanently, though weakly, magnetised. sufficing in this case. The elec- This curious result, which is really an off- tric sad iron has also proved to It's Raining in the "Movies." Above We See the Pouring shoot of Rain and Below -A "Terrific" Wind, Created by an Aero- experiments directed to quite a be extremely efficient. plane Propeller Which Drives the Rain Toward the Left. different end, reminds us that magnetism is not a property peculiar to iron, any more German engineers are using zinc wires in Electrically than radio operated locks are now fitted -activity is peculiar to radium. place of copper, which is required for mil- on automobile doors. Pressing a button Iron and nickel are chief magnetic metals. itary purposes. opens the door.

www.americanradiohistory.com THE ELECTRICAL EXPERIMENTER

LEGEND: ELECTRIC BATTLESHIP I- Motor-driven anchor hoists. 2-Heavy gun turret turning motors. 3- Motor-driven gun elevating mechanism. 4- Telephone from gunner to range finders 27A and bridge. 5- Electric firing device on all guns. All guns may be fired simultaneously from bridge. 6- Electric buzzer signal for timing gun firing. 7- Ammunition hoist motor. 8- Electric lights throughout ship. 9- Telephone from bridge. 9A- Loud -speaking telephone from gun turrets to ammunition rooms, etc. Similar service throughout vessel. 10-Electric submarine telegraph. 11-Submerged torpedo tubes fore and 'aft. 12- Fuel oil tanks for boilers. 13 -Fuel oil stored in double bottom of hull. 14- Ammunition rooms serving turret guns. 15-Electrically closed doors operated from and annunciated at the bridge. 15A -Warn- ing whistle for doors 15. 15B- General alarm bells scattered throughout ship for "Battler'muster. 16 -Radio room for general use. 16A- "Battle" radio room; absolutely sound proof. 17- Motor -driven culinary apparatus in kitchen. 18- Electric stoves for cooking. 19- Cable connection for electrically firing guns from bridge. 20- Buzzer signal for timing secondary guns. 21- Motor-operated cranes for lowering boats. 22- Wireless aerial "lead -in" cable. 23- Electric steering and propulsion controllers on bridge -duplicated in emergency pilot room at 26 also in conning tower. 24- Keyboard for signaling by Ardois lamps 29. 24A- Electric wig -wag signal semaphore. 25- Electric search -lights scattered about vessel. 26-Control keyboard for electrically firing all guns in salvos, etc., from bridge conning tower, or below decks.

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Uncle Sam's New 40 -mile an Hour "Electric" Battle- Cruiser By H. Winfield Secor and Arthur C. Doyle* The most wonderful fighting ship ever built by any nation is about to be constructed for the U. S. Navy. It will speed over the seas at over forty miles an hour. The armament will be of the best, the main battery comprising eight 16 -inch guns of the highest power, besides numerous smaller calibre guns. The electric power plant driving the propellers will develop 175,000 H.P., sufficient to operate all the New York Subways. WHILE the foreign powers are next year, will resemble huge blast furn- perts are in hopes that they will tear busily engaged in a titanic aces gone to sea. From their six massive through the sea at 38 knots or more, struggle for the supremacy smoke stacks there will belch forth reel- stripped. This velocity of travel is equiva- of Europe, Uncle Sam's ing black smoke from 175,000 H.P. in lent to about 42 land miles per hour. naval engineers have been boilers. These ships will be designed with These latest bull -dogs of the sea will be also busily engaged, though in a somewhat special regard to the shape and finish of electrically driven and their boilers will be different way. The results of their calcu- the hull, which will have a length of near- of the oil -burning type. It has been speci- lations and researches have brought forth ly 900 feet. The beam of the vessel will be fied that they shall be so equipped that plans for one of the mightiest fighting craft 97 feet, and their full load displacement they can steam along without giving off ever dreamed of, even by naval construct- about 40,000 tons. These marvelous ships, any smoke from their stacks, when it is ors. In short, these new ships, four of the greatest of their kind ever designed, are desired to conceal their movements. They which have been authorized to be laid down scheduled to attain a speed of 35 knots with are to be so arranged that when desirable, `(Formerly Chief Electrician U.S. Navy). full equipment aboard. And the naval ex- for maneuvers, heavy banks of thick, black

www.americanradiohistory.com THE ELECTRICAL EXPERIMENTER 479

26A- Signaling lamp on forward mast head. 26B -Speed signaling lamp on 'aft mast head. 27-Telephone on head of range finding officers on masts and other points communicating with gunners and bridge stations. 27A-Range finding telescopes on masts, etc. 29- Ardois signaling lamps operated from keyboard on bridge at 24. 30- Smoke stacks for boilers. 30A- Electrically controlled steam "Siren and "Fog" whistles. 30B- Electrically controlled maneuvering whistle. 31- Electric launch. 32 -Main flue to smoke stacks. 32A- Motor- driven washing machine in laundry. 33-Oil burning boilers. 34- Air -spray oil burners in steam boilers. 35 -Air pumps for lifting fuel oil from double bottom or tanks. 36 -Air compressors (all motor driven) for oil spray burners, etc. 37 -Steam turbines driving electric generators 38. 39 -Main electric distribution switch -board. 40- Remote control switch -board linking bridge with propeller and rudder motors, et cetera. 4I- Electric propeller motors controlled from bridge (23), conning tower or pilot room below decks. 42- Propeller shafts. 43- Evaporator plant (motor-driven), producing drinking water from sea water. 44- Motor-driven fans to circulate fresh air through lower decks of vessel. 45 -Fresh air funnels supplying fans, etc. 46 -Helm or rudder motor controlled from bridge (23), conning tower or pilot room below decks. 47- Electric helm indicating switch device; shows by numbered lamps at 23, exact position of the rudder. 48-Two "Battle" wireless antennae supported on both sides of war- ship, thus giving 3 aerials in all. 49- Microphone system for detecting submarines. 50- Electrically released self-illuminating buoys. Push over -board. of a button throws them into the water when man falls

43e. 32

PROPELLERS

smoke can be rolled out of their stacks, The General Electric Company will in- gigantic dynamos, together with their driv- forming a veritable cloud bank or screen stall the turbo- electric generating equipment ing turbines, measure 50 feet, 7 inches long to conceal the operations of other war ves- as well as the electric motors, which are di- by 22 feet wide and 15 feet high. They sels behind them. will be placed on two decks, as shown in

11111111111111111111111111111111111111111111 I 111111111111111111 lllllllll 1,111 The general arrangement of the electrical :wi1111111111 ,,ll,,,,l II lll lll lllll .lll the accompanying illustration, according to and other equipment upon these wonderful the present plans. The relatively small Do you know what happens on a space thus occupied by this monster power examples of modern naval architecture, is ship when the ene- shown in our accompanying wash- drawing. modern fighting plant becomes evident when compared to my is spotted? The multifarious the space that would be occupied by Some idea of the vast size of the power by electricity in locat- the plant, or, rather, the vast amount of energy rôles played reciprocating steam engine, used on most ing the enemy war -vessel, and in of the ocean -going vessels. required to be developed by the power firing the guns, propelling and plant, may be had by comparing it for the steering the ship, also many other Another important item is the fuel to be moment with the horse -power developed by highly interesting but generally used under the boilers. This will be petrol- such a central station as that supplying unknown features are explained in eum or other oil of similar thermal value. electric power to the City of New York. this specially prepared and timely And besides that carried as reserve, in When these monster craft develop 175,000 article. tanks, a large portion of the oil fuel will H.P. they will then be producing 25,000 be stored between the two steel skins of H.P. more than the grand total put out by the double bottom of the hull. The very the Fifty -ninth Street Power Station of latest type of specially designed and ex- the New York Edison Company, this sta- rectly connected to the propellers. The tremely compact water -tube boilers will be tion operating the whole New York Sub- electric generating equipment will comprise fitted with highly efficient, compressed air way system. 4- 35,000 kilowatt turbo -generators. These (Continued on page 5331

www.americanradiohistory.com www.americanradiohistory.com THE ELECTRICAL EXPERIMENTER THE ELECTRICAL EXPERIMENTER 479 478

26A- Signaling lamp on forward mast head. 26B -Speed signaling LEGEND: ELECTRIC BATTLESHIP lamp on 'aft mast head. 37- Telephone offices on head of range finding turret on masts and other points communicating with gunners and n anchor 3-Heavy bridge stations. 3 otor Telephone from 2M -Range finding telescopes on masts, em. 20 - detailing mechanism. - Ardols 3-Motor-dawnnw Ru firing signaling lamps operated from keyboard on bridge at 24. 30 finders 2 Smokestacks Conner o range t frombidge. 6- for bollen. 30A-Electrically controlled steam "Siren" gu guns may be fired simultaneously rom and "Fog" whistles. all firing. 7 eh hoist 35B- Electricallycontrolled maneuvering whistle. Electric buzzer signal kw timing Rho 31- Electric launch. 32-Main flue to smoke stacks. tights throughout ship. 4.. 32A- Motor- O- Elotric turre to ammuni- driven washing machine In laundry. 33-Olt burning boilers. 34- from gun -spray bridge. OA-Louelephone vessel. Sub- Alr oll burners in steam boilers. 35-Air pumps for lifting fuel etc. Similar throughout tion ro ms, des fore 13- oll from double bottom or tanks. 36-Alr compressors (all motor telegraph. II-Submerged driven) for oll spray marine oil stored in double burners, etc. 37-Steam turbines driving electric Fuel oil tanks for boilers. 13-Fuel generators 38. 39 -Main electric board. 46-- serving 15-Electrically distribution switch- at the dge.ISA `Varn R mote control switch-board linking bridge with propeller and rudder doors operated frrom and annunciated y motors. closed bells scattered through- et cetera. 41-Electric propeller motors controlled from whistle for doors IS. 1513-General alarm bridge ß3I, ing room for general use, I6A- conning tower or pilot room below decks. 42- Propeller out ship for "Batllet'muster. 16--Radio shafts. 43- Evaporator sound proof. 17- Motor-driven plant (motordriven), producing drinking "gattle" radio room; absolutely 19- water from sea water. 44- Molor.drhen fans to circulate fresh ale kitchen. 18-Electric stores for cooking. culinary apparatus In bridge. 20- Burrer through lower decks of vessel. 6S -Fresh air funnels supplying fans, connection for electrically firing guns from Cable 21- Motor-operated crones for etc. 46 -Helm or rudder motor controlled from bridge (23), conning signal for timing secondary Rum. tower or pilot room below decks. Electric helm 'Irelrss aerial "lead-in" cable. 33-Electric 47- indicating switch lowering boats. fl- in emer- device; shows by numbered lampa at 23, °met position of the rudder. propulsion controllers on bridge--duplicated steering and for sig- 48-Two "Battle" wireless antennae supported on both sides of war- room at 36 also In conning lower. 24- Keyboard gene) pilot ship, thus giving 3 aerials in all. Microphone system for detecting lamps 29. 21A- Electric wig -wog signal semaphore. 49- naling by Ardols Control key- submarines. 50- Llectricatty reteased self- illuminating buoys. Push Electric search -lights scattered about seseeh 26- 25- from bridge of a button throws them into the water when man falls over -board. board for electrically firing salvos, etc., connng tower,o i g, ns below

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PROPELLERS FUEL OIL IRDOUBLE BOTTOM.'

took on be rolled out of their stacks, The General Electric Company will in- gigantic dynamos, together with their driv- laming a veritable cloud bank or screen stall the turhn- electric generating equipment ing turbines, measure 50 feet, 7 inches long 4 conceal Uncle Sam's the operations of other ves- as as the electric motors, which are di- by 22 feet wide and 15 feet high. They New 40 -mile an "Electric" -Cruiser xIs war well Hour Battle behind them. will be placed on two decks, as shown in By H. Winfield Secar and Arthur C. Doyle° The general arrangement of the electrical the accompanying illustration, according to The must wonderful fighting the ssod other ship ever built by any nation Is about to be constructed for the U. S. Navy. It will speed over equipment upon these wonderful the present plans. The relatively small seas at over forty miles an hour. rimpks know what happens on a The armament will be of the best, the main battery comprising eight 16 -Inch of modern naval architecture, is Do you i space thus occupied by this monster power guns of the highest power, lose in fighting ship when the enc. besides numerous smaller calibre guns. The electric power plant driving our accompanying wash- drawing. modern plant becomes evident when compared to the propellers will develop 175,00011.P., stole idea The multifarious sufficient to operate all the New York Subways. of the vast size of my is spotted? the spice that would be occupied by the Its the power in locat- i3 or, by electricity j W':(ILL the foreign powers tear "4 rather, the vast rôles played reciprocating steam engine, use d on most are next year, will resemble huge blastt hopes that they will amount of energy and in {1 busily fuiv perts are in ing the enemy war -vessel, of the ocean-going vessels engaged in a titanic aces gone sea. or owe. 'malted to be developed by the to From their six massive through the sea at 38 knots Ihnt, may power the guns, propelling and struggle for the supremacy cqo be liad by firing Another important item is the fusel to be M 's smoke stacks there will belch forth reel- stripped. This velocity of travel is comparing it for the also many other of Europe, Uncle steering the ship, used under the boilers. This will be petrol- Sam's ing black smoke from 175,000 H.P. in lent to about 42 land miles per hour Inhatcesiralestation but generally naval engineers have k highly interesting eum or other oil of similar thermal value. been boilers. These ships will be designed with These latest bull -dogs of the sea will pas °thatvsuoplyingsupplying are explained in also busily engaged, though in a 6e Pik Power to unknown features And besides that carried as reserve, in somewhat special regard to the shape and finish of electrically driven and their boilers will the City of New and timely f¡ different way. The results of their calcu- this specially prepared tanks, a large portion of the oil fuel will the hull, which will have a length of near- of the oil- burning type. It has been sáhat HP will craft develop 175,000 lations and researches have brought Larticle. be stored between the two steel skins of forth ly 900 feet. The beam of the vessel will be fled be so equipP, then be producingroducin5,0(10 2 plans for one of the mightiest fighting that they shall P. fare than w..1 the double bottom hull. craft 97 feet, and their full load giving. a. the grand total of the The very ever dreamed displacement they can steam along without is put out by of, even by naval construct- about 40,000 51 ESdtLeent latest type of specially designed and ex- tons. These marvelous ships, any smoke from their stacks, when etw ors. In short, these new ships, four of the Yorke propellers. The tremely compact water -tube boilers will be greatest of their kind ever designed, are desired to conceal their movements..Tey boil Coz an th stoa-f r ctly connected to the which have been authorized to he laid down scheduled the fitted with highly efficient, compressed air to attain a speed of 35 knots with are that when desirabx whole New YSt k Sub- e ectric (Farmnfy Chief Electrician U.S. Nary). to be so arranged Mkt t) system. These (Cpntinued on page full equipment aboard. And the naval ex- for maneuvers, heavy banks of thick, kilowattgtnrbógeneratore. 533) www.americanradiohistory.com 480 THE ELECTRICAL EXPERIMENTER November, 1916

COOKING EGGS BY A, is held in a nickel plated base, B, by well will boil out and be condensed on the ELECTROLYSIS means of a special bolt. The porcelain dish cover, meantime, cooking the eggs to the An ingenious electrical cooking device has a small well, C, located in its center desired point. Finally, the water will all be has recently appeared, which, among other and in which the two carbon electrodes boiled out of the well, thus automatically novel features, does not make use of heat D are placed. The. cover, F, sets in the turning off the current just when the eggs groove, G, of the dish, A. This have reached the desired turn to suit the groove is of sufficient capacity to individual taste for which the water meas- hold as much water as the well, C, ure was set. will hold. It is interesting to note that not more The eggs, E, are placed in a per- than 1% teaspoonfuls of water need be forated metal holder. A separa- ble plug is connected to a flexible cable which leads the current to the two carbon electrodes. The operation is as follows: 'A measured quantity of water is placed in the well from a measure. The measure is filled up to the desired point by covering one or more of the holes with the fingers, thus determining the degree to which the eggs will be cooked, whether soft, medium, or hard. %Vhen the current is turned on a sufficient 1 quantity flows through the water and the carbon electrodes to cause the water to boil almost immediately. The resistance of the water is Í materially reduced by the carbons, which contain sufficient salts to insure satisfactory operation at all times. Salt should therefore never To Cook Eggs to Just the Right Degree, a Meas- be added to the water. ured Quantity of Water Is Placed in the Lower For the uniform cooking of Receptacle C. Ebullition Is Produced by the dif- Electric Current Passing Thru the Water; Finally ferent size or different numbers of All the Water Condenses on the Cover F, and The Latest Device for "Cooking" That Great American eggs it will be apparent first of all Into Groove O, Thus Cutting Off Current. Breakfast Essential-the Egg. The lien -Fruit Are that the amount steam condensed Steamed, Not Boiled, and This Is Said to Make Them of Extremely Edible. on the surface of the egg will be ap- boiled to cook four eggs, as compared with proximately proportional to t h e the kettle full that used to be necessary. developed in resistance wires, but instead amount of heat absorbed by the egg. Thus, The economy of this must be obvious. steam is formed by the passage of current when steam first begins to form, the eggs are Furthermore, no one who has eaten eggs directly through a small quantity of water cold and will absorb a great deal of heat cooked by steam will ever want to eat the in sufficient quantity to cause the water to and the condensation on their surface will be old fashioned boiled eggs again it is boil. This device is used principally for great. It is obvious that a large egg with a claimed. The whites are never tough as cooking eggs, and in this connection the greater surface will condense more steam they are in boiled eggs, but always tender use of a graduated quantity of water will than a smaller egg. Now, as the eggs are and delicious. allow of a regulation of the degree to which placed directly over the sloping sides of the This same device when used for warm- the eggs are cooked, without any further bowl, all this condensed steam will run into ing babies' milk is a household convenience watching; the circuit breaking automatic- the well and will be evaporated by the heat- that fills a long felt want, It is 'impossible ally when the water has been boiled away. ing action of the electric current. On the to burn or scorch the milk atilt it is un- The cooker is so arranged that it will cook other hand the steam which is condensed on necessary to watch it while it is warming. the eggs to the same extent, whether there the inside of the cover will run down inter Other possibilities for this form of elec- is one egg or more and whether the eggs the groove G and remain there. Therefore, tric heater are being developed{;,, as it is are large or small. when the eggs have become heated to the apparent that it can be applied for all sorts A description of this device will make point where condensation no longer takes of steam cooking as well as warming liq- these points apparent. A porcelain dish, place on their surface, the water in the uids and sterilizing material by steam. AN ELECTRIC LAMP FOR THE A SHOCK -PROOF SWITCH FOR shut to prevent unauthorized persons over - MICROSCOPE. "SAFETY- FIRST." fusing the switch or tampering with live, The lamp here illustrated is constructed Each year the newspapers print accounts connections. to throw the light either on the mirror or of accidents resulting from the use of the Photo Western Electric Co. directly up through the condenser of the open type switch microscope. It gives illumination sufficient widely used in indus for oil immersion work. It is small and trial plants. Often compact yet very efficient and is neatly fin- such accidents go un- ished in black crystal lacquer. No light can recorded, but were it escape except through the single opening. possible to make an It is equipped with a 10 -watt Mazda tungs- accurate accounting the total would probably be surprisingly great. The enclosed switch here illustrated offers a complete remedy for the open switch evil. The switch and cut- out unit are completely enclosed in a metal box provided with a hinged cover which is held closed with a A Miniatir Certs Lamp w:::.'. (ves Effect simple spring catch. of Daylight for Microscopic Requirements. The switch is opera- ten bulb, and works on any 110-volt cir- ted by a crank handle cuit. It can be used on 220 -volt current located outside t h e when placed in series with proper resis- box. It may also be tance. The microscope lamp is supplied locked in the off posi- with blue and ground, and Daylite glasses; tion to prevent acci- the latter, when placed in front of a nitro- dent when repairs are gen -filled tungsten lamp, gives a white light in progress. Means having the same color and spectral energy are also provided to A "Safety- first" Electric Service Switch which Can Be Locked in the distribution as natural daylight. lock or seal the cover "Off" Position.

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 481 PRESSURE OF FOOT CONTROLS Charles Proteus Steinmetz This Month's Supplement THIS SEWING MACHINE MOTOR. CHARLES PROTEUS STEIN - order that they may be able to gain suf- The women folks like handy devices, es- METZ, the subject of our photo- ficient technical educational to enable them pecially electric devices -but above all else, graphic supplement with this to hold positions of responsibility with they must be simple and efficient. This ap- number of TILE ELECTRICAL Ex- greater remuneration than that accorded plies particularly to electric drives for sew -, PERIMENTER, is perhaps the most to the unskilled. ing machines; a large variety of speeds are widely known electrical engineer in the Also Dr. Steinmetz has a class in elec- very desirable for such work, but the or- Western hemisphere, and his fame has trical engineering at Union College, and dinary rheostat used for controlling the spread to practically all parts of the civi- this Institution gave him the degree lized globe. of Doctor of Philosophy in 1903. In his official capacity, Dr. Steinmetz Some idea of the responsibilities serves as Chief Consulting Engineer of the and important work performed in vast General Electric Company's works in the electrical field by this peer of Schenectady, N.Y. electrical engineers may be gained This accomplished scholar and technician, from the fact that he receives the whose name is practically a household word largest income ever paid to anyone in the United States at least, started his in a similar capacity, which amounts career in a very inauspicious manner; and to $100,000 a year. yet again, some would call it a very aus- Dr. Steinmetz is very short in picious manner. stature and somewhat stooped. He He was born in Breslau, Germany, in is always ready to talk on any sub- 1865, and when he grew up he associated ject owing to his extremely broad with a number of the most radical So- education. And he still believes in cialists in Germany. In fact, he was placed Socialism -even for Americans. He in jail with a number of Socialists, but as is said to have but one suit and to nothing could be proved against him, he wear no hat at all -true Socialism. was released. One thing led to another His interviewers invariably find him however, and so it came about that he be- puffing away at a long black cigar. came what Americans term "an undesira- With his manifold duties as Chief ble citizen," at least from a German po- Consulting Engineer to the might- litical viewpoint. The upshot of these mat- iest electrical corporation of all ters was that Dr. Steinmetz, then a young time, he has found an opportunity, man, withdrew to Switzerland and eventu- in his spare moments, to write a ally came to the United States. number of electrical books which It was in the year 1889 that this seem- have become classics in the science ingly very ordinary young man reached of electrical engineering. Ask any New York in the steerage of a French electrical engineer or electrical ex- steamship. He carried letters of high rec- pert as to what books he considers The Harder You Press on this Foot Rheostat the Faster ommendation from his professors at Bres- the most valuable in his library and the Motor Runs. lau and the Polytechnische in Zurich, but he will answer you in one word - his pockets jingled not with the coin of the Steinmetz ! motor current gives only a few variations realm, or, at least, not above a few dollars. in speed at best. He finally procured a position as drafts- A FARMER PUZZLES THE TELE- In a recent sewing machine controller put man, which, although opening excellent GRAPH EXPERTS. on the market there is inserted in the cir- channels for his intellectual proclivities, cuit a coil of wire with about 120 turns did apply- Up in northern New York during last such high to block not prove of sufficient scope for August a farmer with good intentions. but of resistance as the ing the vast knowledge which he had accu- slight knowledge of the circuit completely. This coil is placed mulated in the mathematics, characteristics of neat metal -box, with a subjects of the electric fluid, created a lot of trouble inside a treadle physics, chemistry and medicine. for slightly curved strip of phosphor bronze The company with which he had become the board attendants and quad men of above it and the The the Western Union Company at New York, just under treadle. associated in the capacity of draftsman was Syracuse, coil is well insulated by a special cement, finally absorbed by the General Electric Watertown and Ogdensburg, says except directly beneath this strip. As the Telegraph and Telephone Age. At a point Company, and it was not many years be- where operator presses her foot upon the treadle, Charles P. had the poles carry half a dozen or more strip bronze is pushed fore Steinmetz made a naine of the principal the of phosphor for himself; in fact, such a name that he wires that terminate at down upon the resistance coil. On account Ogdensburg, the farmer wished to pass un- was appointed head of the Consulting En- der of its curved contour, it does not, under a gineering Department of the Company. the wires with a load of hay, but found moderate pressure, come in contact with This was but five years after he had that his load was too high. He solved his all the coils. Those with which it does reached America. difficulty by encircling all of the telegraph make contact, however, are short circuited, wires with a piece of his own wire in The name of Steinmetz is synonymous used thus reducing the resistance of the entire with mathematics binding bales of hay. This he drew tight, unit and permitting the passage of some to most people who know raised the on, leav- even the least bit about him, and he him- obstruction and drove current. The harder the operator presses ing his "tie wire" in place for the benefit of upon the the more the is self has said that he attributed all of his other farmers who might wish treadle, strip success and advancement to his excellent to pass that flattened out and brought into contact with knowledge of mathematics. way with loads of hay. the coil. The more of the coil is short-cir- This happened shortly before noon. the more current is allowed to pass. He takes active interest in various phases Business between New York and Ogdens- cuited, of educational work and serves as president burg stopped suddenly. The wire experts of the National Corporation of soon developed the worst "cross" they had Schools. This association aims to give industrial ever met with. Upon opening all but one training to grade -school boys in of the circuits they could work through the remaining one 11111.1111111111111111,111 after a fashion. Selection ,,,.,,,,,,,,lll 11111111111 lllll ,1,111111111111,1,,,1,11111, 11111111111 lllll111111,111111,.' $ at random was as good as using the same WITH THE DECEMBER ISSUE wire at both ends, provided all the other circuits were opened. we will present another This state of affairs lasted until the middle of the afternoon, adding gray }lairs to SUPPLEMENT the heads of the experts and emphasis to their remarks. Suddenly normal conditions of a famous radio inventor. This returned. Later in the day the lineman's is the second of a, series promised to our readers. report cleared up the mystery. These supplements are printed on LITERALLY. Detail View of Foot -controlled Motor Rheostat fine art paper, ready for framing. which Operates Sparklessly. They are invaluable to adorn your "Here are a lot of suggestions from out- den, your wireless station, or your siders as to how to run this newspaper. With increased current, the motor, and laboratory. See that they are carried out," said the with it the machine, runs faster. There- Order your copy now, to make editor. fore the operator has, theoretically, 120 sure you will get it. "Yes, sir," said the office -boy, and, put- different speeds at her disposal and the ting them all in a waste -paper basket, he harder the foot pressure is the faster the promptly carried them out. machine will run.

www.americanradiohistory.com 482 THE ELECTRICAL EXPERIMENTER November, I916

NEW ELECTRICAL METHOD OF of the silverware, there is now an electro- A recent report made to the American. CLEANING SILVER-A HELP lytic method of quickly and efficiently clean- Chemical Society on this electrolytic meth- TO MOTHER. ing such silverware, no matter how soiled od of cleaning silver by contact with alumi- Most of us have seen our women folk or discolored it may be. num in an alkaline solution, mentions endeavoring to scour or polish silverware, The illustration herewith shows the sim- among other things: that a number of care- particularly the discolored knives and forks, ple "apparatus" required to carry out this ful tests proved that sodium carbonate was process. It is necessary to purchase a small slightly more efficient than the sodium bi- aluminum pan about eight or ten inches in carbonate. The best concentration for the diameter, which may be of any shape. Be solution was found to be that calling for sure that the vessel is of aluminum. A suf- one teaspoonful of washing soda and one ficient quantity of bi-carbonate of soda, teaspoonful of table salt to each quart of costing less than ten cents a pound, is then water. Best results were obtained in these placed in the pan with boiling water to give a saturated solution. This is placed on the kitchen stove, so as to be kept thoroughly hot while the discolored silverware is immersed in the solution and allowed to rest on the bottom of the pan. It should be noted that the various silver pieces must not touch each other, but they must invariably touch the aluminum vessel. An electrolytic action is set up so that current passes between the aluminum con- tainer and the silver pieces, and the latter, being positive to the aluminum, causes in consequence an extremely slight amount of To Clean Even the Dirtiest Silverware. Procure the silver to be disintegrated from the ware. an Aluminum Pan and Mix up a Strong Solution This of course results in the incrustation of Bicarbonate of Soda. Keep it Boiling and being removed also, and when the process After the Spoons, etc., Have Laid on the Pan Bottom for a Few Minutes, They will be. Found is finished and the solution emptied out of to be Thoroly Clean. Cleaning Silverware Is no Longer a Detestable pan, will be a blackish and Aggravating Task, Thanks to the Electrical the there found de- Method of Cleaning it Here Described. posit adhering to the sides and bottom of tests when the cleansing solutioif was main- the aluminum vessel. This represents silver tained at the boiling temperature during the by any one of several well -known first- oxide and other matter which has been elec- process, and aluminum proved more efficient hand methods involving the use of ashes, trolytically removed from the silverware, than zinc for use as the active metal in con pastes or compounds variously guaranteed leaving the latter in a practically new contact with the silver. to shine anything, even down to lead. And dition. Principally, this method results in a dis- most of us know what an unpleasant and Contrary to general opinion, this process tinct saving in labor, and it is, besides, very thankless task this is to everyone whose lot is not injurious to the silverware. The convenient and clean. To quote the report it is to perform it. amount of silver disintegrated or deposited in question: "It removes the tarnish from Instead of scouring the knives and forks in the bath is so very slight that it amounts both the sterling and plated silverware and taking the chance of marring the finish to almost nothing. without appreciable loss to the metal." WHISTLE, AND THIS ELECTRIC illustrated in figure. The mechanical and paper writes him up, at any rate. His latest TOY BANK GRABS YOUR COIN. electrical details are apparent from lower claim to the title of champion heavyweight A very interesting electric toy bank has figure. The novelty of this toy lies in the patentee of the United States is a corn - been recently invented by Christian Berger, that that the coin which is to be deposited bination electric motor horn and signaling the well -known inventor of the submarine in the bank is placed upon a horizontal plat- device for the front and rear of a motor wireless apparatus and of the various elcc- form, and by the aid of a whistling sound car. it is automatically deposited. This is done The device consists of a handsome fig- by means of an electro-magnet acting upon ure -the inventor says he will make it to the platform which is controlled by a spe- suit any taste, from Venus to Charlie Chap- cial microphone, connected with a battery. lin -and a horn of unlimited possibilities. Referring to the second figure, it will be The horn possesses remarkable noise -pro- noted that the battery is held in a suitable ducing qualities- enough to wake the dead,. receptacle as shown on the left. The coin avers the sponsor of the magnificent look - door is in the foreground center and can be ing specimen of manhood here portrayed.. seen by referring to Fig. 1 (at the top) show- When the driver presses the button the ing the circular opening. The microphone is located in the right compartment and consists of a fine wire pivoted on an insulating rod. The end of the wire bears lightly upon a piece of gold foil fastened to the side of the safe, which latter is made of thin sheet metal. The electro- magnet used for retaining the coin platform horizontally is located at the bottom. The connections are made the same as for the Electric Dog, described in our June issue. The operation of the toy is as follows: The money which is to be deposited is placed upon the platform, Fig 1, which is pulled down until the electro-magnet holds it and keeps it in a horizontal position. By producing a sound such as clapping one's hands or whistling, so as to actuate At Left: New Shrieking Auto Radiator Decora-. the sensitive microphone, the coin platform tion. At Right: Direction Indicator and Tail. is released instantly and deposits the money Lamp; Both Electrically Operated. through the upper hole, Fig. 1. figure's arm goes up in a menacing manner, The safe is fitted with a door and lock is- at the back for the purpose of removing the mouth opens wide and wild shrieks the money collected therein. sue forth. For the rear of the car Mr. Sieben has added a direction indicator and_ tail lamp to his device. AN ELECTRIC MOTOR HORN Should the driver desire to turn to the Whistle but Once and This Electric Bank Hustles WITH TRIMMINGS. arm of the figure in'the rear will Your Coin into the Vault. left, the Henry Sieben, past wharfmaster and past point in that direction. At the same time- tric toys which appeared some time ago in master of plain and fancy inventing, has the mouth will open and the same wild this journal. added another to his list of momentous shrieks emanate. On the figure's chest: The bank as it appears when finished 3s contraptions; this is the way his local news- there reposes the tail l:ght.

www.americanradiohistory.com NOVt.ttii)Cr, 1916 THE ELECTRICAL EXPERIMENTER 483

PICTURING ELECTRIC SERVICE Madison Avenue, New York City. In ac- ination cabinets which are used in the TO AMERICA'S MILLIONS. cordance with the rules of the contest, the manner shown, the patient standing be- Poster Committee appointed by the Amer- hind the cabinet and the fluoroscopic image IMAGINE nearly 800 posters, all in col- ica's Electrical Week Executive Committee, being cast upon either of two rising and ors, all by individual artists, and you then turned over to the judges the entire falling screens. have an idea of the task before the collection of posters. The X -Ray tube of large size, measuring judges who recently selected the prize win- The judges were further instructed to about 12 inches in diameter and provided ners in the America's Electrical Week post- select those er competition conducted by The Society posters which for Electrical Development. The competi- should be classi- tion closed June first. Over 800 posters fied as eligible received representing $100,000 were over for t h e public worth of designs. vote to decide Since America's Electrical Week appeals the winner of a alike to rich and poor, man and woman, special $300 Pub - merchant and customer, artist and engineer, lic Choice Prize. everybody was asked to suggest a fitting de- In this way the sign to drive home into every hamlet and Society for Elec- city in the land, the message -"Do It Elec- trical Develop- trically l" ment relieved it- The judges were unanimous in their self entirely choice-which is shown here. In colors it, from the judg- of course, is many times more effective. ment of the The judges are recognized as representa- posters and tive commercial art critics. placed all the re- The poster might well be entitled "Alad- sponsibilities in din; Symbol of Service." the selection of Of all the Arabian Nights Tales, the story the prizes upon of Aladdin is, perhaps, the most fascinat- this Jury of ing. The all- powerful slave, who could be Awards. The So- summoned by the mere rubbing of a mys- ciety cxercised no terious lamp; the treasures thus at the com- influence upon mand of the lamp's owner; these make a the determina- narrative which will live as long as the pic- tion of the prizes world lives. Yet the modern Aladdin, and left the de- tured in this poster, performs wonders that make the adventures of our Arabian Nights cision of t h e insignificance. awards exclu- hero pale into sively to t h e Gone is the ancient lamp. Now it is the judges. gentle touch of a button and forthwith He After many comes the Genie, Electricity. bears, not deliberations, the precious stones, but things far more pre- judges elimina- cious- Light, Heat, Power. It is the power heat ted all posters that makes the world go 'round, the not entitled to be that forever drives out cold, the light that considered f turns night into day. o r and the Public's And this wonderful Genie comes Choice goes, as did Aladdin's, at our bidding. He Prize. How Some 125 post- is always "at your service." better ers survived this could the thought of America's Electrical test. The judges Week, "Do It Electrically" be presented to then determined the people? the This design will be used throughout the winners of campaign, millions of poster stamps, win- all of the prizes Photo from Jacques Norsr bill except the Public French Physician Examining Entire Chest of Patient with High Power X -Ray dow and car cards, lithographs, post- Choice Prize. Set. Insert View Shows X -Ray Skin Growths at X, Resultant from Over - ers, in newspapers, magazines, etc. It will Exposure to These Powerful Rays. be reproduced at least 200,000,000 times. The prize winners were then voted on with the follow- with water cooling attachments to carry ing result: off the heat from the heavy current used, No. 717-the first prize of $1,000 -Harold is supported behind the patient so as to von Schmidt, San Francisco, Cal. throw the X-Rays through his body onto No. 174 -the second prize of $500 -John the fluoroscope screen mounted in front A. Bazant, Bronx, N.Y. of the cabinet. At the left of the picture No. 452 -the Art Students prize of $200 may be seen part of the X -Ray stand and -Edward Staloff, Jersey City, N.J. holder with regulating apparatus on it for No. 392 -the first school prize of $100- timing the length of the radiographic ex- Harold H. Kolb, Somerville, Mass. posure. This timing of the exposure is ac- No. 80-the second school prize of $50- complished by means of a special clock - Wm. E. McKee, Jr., Hollywood, Cal. work mechanism. No. 84 -the third school prize of $25- Naturally the exposure to the X-Rays Armand Moreda, Brooklyn, N.Y. must not be too long or else the patient is No. 576-the fourth school prize of $15- liable to have his skin burned. In the case Ruth M. Jameson, Buffalo. N.Y. of special investigations and where con - No. 720 -the fifth school prize of $10- siderable research work is carried on in Edna E. Crowley, Chicago, Ill. this direction there is a danger of con - This decision made No. 717, entered by tracting a serious growth caused by the Harold von Schmidt of San Francisco, the X -Rays and a specimen of which is shown official design for America's Electrical in the lower right -hand corner of the illus- Week. It is interesting to note that this de- tration -the growth somewhat resembles sign, although not the winner of the Public a wart, appearing in this case on the fingers Choice Prize, figured prominently in the of the hand and the principal ones marked public voting wherever exhibited; this fact by crosses. confirms the judgment of the jurors that The cabinet which encloses the patient poster No. 717 carried a strong appeal to as shown herewith is therefore lead lined. America's Electrical Week Poster. Winner of message electric Grand Prize of $1000 In Nation -Wide Electrical the public, and that the of lead having been found to be a very good Poster Competition. Over 800 Leading Artists service at the push of a button set forth in screen or shield for the X -Rays. The par - Submitted Designs. This Design Will be Re- the design "gets across.' produced 200,000,000 Times During the Big Cam- titular outfit here shown is of French de- paign This Fall. LEAD LINED CABINETS REDUCE sign and there are also provided special The posters were assembled for the in- X -RAY BURNS. rubber gloves impregnated with lead salts, spection of the judges on June tenth in the In the illustrations shown herewith we which help to protect the surgeon and phy- Anderson Galleries, Forty-first Street and see one of the latest French X -Ray exam- sician to a still greater extent.

www.americanradiohistory.com 484 THE ELECTRICAL EXPERIMENTER November, 1916 The Sperry 1,280,000,000 C.P. Searchlight Throws Beam Over Fifty Miles pEOPLE residing within fifty miles area. This is accomplished in the Sperry the mirror, thus, also, adding more reflected of New York City have been sur- arc by maintaining a very deep crater in light to the beam. prised to see an extremely power- the positive carbon and into which crater The principle upon which satisfactory op- ful searchlight ray sweeping over this bright vapor is kept pressed. This va- eration of this high intensity arc depends the sky at night during the Fall por causes the mouth of the crater to emit now shows itself to be entirely different months. This penetrating flash of light a very intense illumination running, for ex- than previously supposed. It was first be- ample, as high as lieved that current density was the prin- 500 candlepower cipal factor for the operation of such arcs, per square milli- but we have found out experimentally by met e r, or 320,000 current densities ranging from 100 to 1000 candlepower p e r amperes per square millimeter that current square inch. T h e density is not the controlling factor, but force used to keep that current value is the important factor. the vapor pressed It is evident that to obtain this highly con- back into the crat- centrated light source and at the same time er of the positive produce constantly a sufficient supply of is the arc flame bright vapor to fill the positive crater, a from t h e negative rapid consumption of the positive electrode carbon and is simi- is necessary. It is for this reason that the lar to the arc flame positive carbons are so much longer than used in the old those previously used, being 44 inches for standard search - the standard 150 ampere arc. In the old light lamps. T h e type searchlight arc rapid consumption of arc flame appears the positive was not necessary since the as a flame of con- gaseous products were not used at all in siderable velocity the production of light, but in the Sperry emanating type of arc this rapid burning of the posi- from tive is necessary to provide the light emit - the negative car- ting, gaseous materials. bon, and gives but The Sperry interests after two years ex- very little light in perimentation with this new form of arc, either the old or are now manufacturing projector search- Sperry type of arc lights giving a candlepower intensity at the as compared with arc for a 36 -inch size, which, aside from the positive crater. the accompanying reduction in the diverg- T h e following ence of the beam gives an illumination on tabulation of the the target of six times that formerly ob- specific brilliancies tained with the older type searchlight of in candlepower per similar diameter. square millimeter, An elevation of the Sperry searchlight at Fig. 2. The control box con- and which is right- is shown tains a shunt wound motor (right) direct ly taken as the bas- connected to both a centrifugal blower is of efficiency - and a gear train for the feeding and ro- comparison for all tating mechanism. The blower furnishes trc work, shows air through two passages to the posi- Photo Copyright by Underwood & Underwood. this tremendous tive and negative carbon holders re- Fig. I. This Powerful Electric Searchlight Throws a 1,280,000,000 C.P. Beam light intensity of spectively. The air supplied to the positive of Light Which May Be Clearly Seen Over 50 Miles Away. the new Sperry holder is forced between a number of heat arc: radiating discs which surround the end of had its origin in Brooklyn, N.Y., where Ordinary Tungsten filament 2.4 to 5.4 the holder nearest the arc. The cap is Mr. Elmer A. Sperry, the gyroscope special- Ordinary Tungsten filament, open on the upper side to allow the air ist, and his engineers, have been testing out nitrogen filled 10.0 to 20.0 to escape from the positive holder. This the merits of his new electric projectot. Tungsten at the melting point, method cools the positive carbon and also It is said to be the most powerful in the (3500° C.) 72.0 removes the heat from the mechanism of world, its scintillating rays having been seen Arc flame, ordinary white the positive carbon holder, received mostly over 50 miles away. The searchlight shown flame arc 7.0 to 20.0 by direct radiation from the arc. in the photograph, Fig. 1, is nine feet high, Surface of crater "spot," while its accurately polished reflector meas- flame arc positive 50.0 to 90.0 ures five feet in diameter, and it produces Crater surface pure carbon is a candle power of 1,280,000,000, which average . 150.0 some light. The Sperry arc being the Up to the present the source of light candlepower of dense posi- which has been universally used has been tive vapor in deep crater of the positive crater of a pure carbon arc. a two-flame arc, special pro- This pure carbon crater has a fairly con- jector electrode 500.0 stant brilliancy of approximately 150 can- Sun at 30° elevation 775.0 dlepower per square millimeter, and it has been considered that this was the highest Another distinct advantage which the attainable brilliancy. It is true that the old new arc has over the older form lies in the standard searchlight arc gives the highest very great reduction in area of the light brilliancy obtainable from a heat radiating giving source or crater. It is possible by' solid, since carbon has the highest melting using this new type of arc to concentrate point of any known element, but this bril- the vapor into a crater which has a very liancy has been surpassed in the Sperry arc much smaller mouth area than heretofore by making use, in addition to this heated possible with a pure carbon arc of similar a superheated vapor or amperage. A distinctive advantage results crater surface, of crater, in gas produced in the arc, says Captain Adel- from this reduction in area of the U.S. Coast Artillery that the angle of spread of the searchlight no Gibson, of beam itself is materially reduced and the Corps in the Aerial Age Weekly. This beam made much more nearly parallel superheated gas is formed from certain throughout its length. For the standard Fig. 2. Electrical Operating Mechanism of New special materials that are powerful light 150 ampere arc, the diameter of the posi- Sperry Billion Candle -Power Searchlight. producers and with which the positive car- tive carbon is only 34 inch and that of the bon is impregnated. crater diameter somewhat less. The diam- The positive carbon is rotated, being con- For the successful use of this bright eter of the negative carbon is only 7/16 nected to the shunt motor through a ver- vapor as a searchlight source, it is neces- inch and with its smaller holder casts a tical shaft and a worm gear. A small sary that it be concentrated in a very small very much smaller shadow on the center of (Continued on page 524)

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 485 The Marvels of Modern Physics By Rogers D. Rusk, B. Sc. THE WIRELESS ERA. varies accordingly, producing an undulatory less era for a while somewhat unduly in- T11E Wireless Era is a name fre- motion of the ether. That is, the field about flamed the imagination of the public. Let quently given to the scientific the wire rises and falls periodically. With us look at the facts. period upon which we are now an ordinary alternating current the strain It is very significant that one prediction entering, by people who realize in the ether is most noticeable just about of a few years ago has not been realized, only vaguely themselves what the wire and becomes negligible a short dis- and that was concerning the wireless trans- they actually mean by it. In reality there tance away, although theoretically the waves mission of power. l'ow'er and energy are may travel at each reversal a long distance before being dissipated. Let us raise the

potential and frequency, however, and see \ 1 } \ what happens. The field rises to full qC .- \l strength in a very short time, and the waves / \l \ B follow each other at a greater speed. This r iii 1 ' / means that radiation is going to amount to l r % I i much more than before. The waves are going to be stronger, and their number will be multiplied many times. If instead of using a wire to direct the energy from A to B, we shorten the circuit very much, rf fig. 2 making it merely a local circuit at A, and if Illustratinkt 'low a Current of Electrical Energy we put another small or local circuit at B, Representing the Detection, at a Point 'B," Is Transmittz.d by Ether Whirls to a Point by a of Radiant Electric Energy. Conductor. then some of the radiant energy from A will be intercepted at B, and these waves pass- two different things. Energy is is a surprising wire ing B will induce a slight current at B. any capaci- relation between and ty for doing work, while power is wireless transmission. That they are not This is wireless transmission. See what a the rate gradual step it is instead of a very sudden at which work is done. Now sufficient ener- distinctly different phenomena may put new gy may be sent across the meaning in the phrase, "Wireless Era." one from wire to wireless transmission. In ocean to easily one case we have a small radiation factor, operate a delicate dctector, but the rate The question has often been asked "Will at which any work is done is ridiculously all wires be done away with in the future ?" due to a real current in a conductor. In the other case we have a high radiation factor minute. Energy has been transmitted but Now the theory most generally accepted at the power was negligible. When a subma- present is that the energy of an electric due to the absence of a long conductor. In the first the_energy is directed; while in rine is controlled at a distance, it is not current in ordinary wire transmission does power from the shore which operates the not reside in the wire, but in the ether sur- machinery, but rather power some rounding is, as from the wire, and that the wire source on board the boat itself which is its name implies, merely a conductor to con- controlled by the energy transmitted from duct or lead the current here or there. To the shore. The strength of the waves de- make this clear, let us imagine a current FINAL CALL crease too rapidly with the distance to al- moving in the wire in Fig. 1, from A to low of any great amount of energy being B and returning by the ground. The dotted / On November 1st, 1916, the transmitted. Most everyone remembers the spiral lines represent the strain in the ether subscription price of "The Elec- rule that the intensity of light varies in- due to the electrostatic and the electro- trical Experimenter" advances to versely as the square of the distance from magnetic lines of force about the wire. The $1.50 in U.S. (Canada the source. Applying this to wireless, and important point to notice is that the cur- and For- eign $2.00.) This is the last chance neglecting other losses, at the distance of rent, without this field, would be lifeless one mile the energy would only be and inert because the magnetic field repre- to subscribe at the old rates ($1.00 sents the energy of motion of the current; in U. S.,Canada and Foreign $1.50). 23,000,000 it would then have no energy of motion, No subscription for more than of its original value. This in itself would for the energy is really stored up in the five years at the old rate ac- stamp the wireless transmission of power ether and is transmitted by it. cepted. THE PUBLISHERS. as impracticable unless a different method Let us look beneath the surface a mo- of transmission than that now in use were ment at wireless transmission. In Fig. 2, discovered. the wireless waves are represented as trav- Nikola Tesla believed he had solved the eling from aerial A to B. We cannot doubt problem and in 1905 took out patents for a for a moment but what the energy is trans- system of wireless transmission of power, mitted by the second, it spreads out in all directions. the ether, as no conducting me- The medium of transmission with the ether as the medium. In brief, dium is present. Therefore, the main dif- of the energy by his system, he intended setting up pow- ference between wire and wireless trans- is the same in either case. The result is that in one case a large per cent of the en- erful, stationary, electric waves, setting the mission seems to be that while in wire reaches whole earth in vibration due to the re- transmission the energy is directed to a def- ergy its destination, while in the other case only a very small per cent does. flection and superimposition of waves from inite point, in wireless it spreads out and all parts of the earth. The principle is sim- dissipates itself in all directions. The field about a wire carrying a direct current acts quite like an invisible whirl- ilar to that of a string tied at one end and A further study of Figs. 1 and 2 may re- waved back and forth by the hand at the veal the reason for this. In a steady di- pool which pulls the electrons, or charged particles in the wire, along. The field, in other. Waves from the hand would travel turn, grows with the current, for the action to the opposite end and be reflected back is an inter -dependent one, and the result is a continuous current. If, with an alternating current, the oscillation frequency is high, the current does not have time between reversals to penetrate the wire deeply, and it is found that the current exists only on the surface of the wire. This is the well known skin effect and shows again that the energy must reside in the external Ï field, and that it takes some appreciable ;`;_ single moving time to start the electrons in motion. This a, a trar>!.' bsfo/roaNy Ware,sach ar7es,b'etrde0, /o fi7/ is what we call a current in a wire. the . . ear/h wi/h. Wireless telegraphy came into prominence fi94 ce in 1896, when Dr. Guglielmo Marconi first demonstrated its commercial value. Since If we Tie a String at one End and Oscillate its This Diagram Gives a General Idea as to How then its importance has increased by leaps Free End Back and Forth, There Will Be "Station- a Radio Station Throws Off "Ether- Ripples" of ary" Waves Set up Along it as at B. Tesla Ex- Radiant Energy, the Same as When You Throw a and bounds. The submarine has been di- pected to Vibrate the Earth with such Waves. Stone into a Still Pond. rected from the shore by wireless; the human voice has been transmitted hundreds (see Fig. 4) creating nodes and loops of rect current the field is steady and continu- and thousands of miles; and various kinds vibration in the string. The proposition, it ous. Change this current, however, to an of mechanism have been controlled by it. was claimed, had been partially demonstra- alternating one and the field or ether strain However, the glaring predictions of a wire- (Continued on page 538)

www.americanradiohistory.com 486 THE ELECTRICAL EXPERIMENTER November, 1916 Baron Münchhausen's New Scientific Adventures By Hugo Gernsback

BEl N G the chief chroni- lion miles away from us. Grad- of a world-famous How the Martian Canals are Built ually the distance was cut down man is never an easy to sixty million miles and his task. Famous men, as a rule, are him several hundred times that the public radio messages easily bridged this dis- most difficult of approach, as they is starving for a message from him. tance, enormous as it was. As will be have a mean trick of keeping aloof of Once prepared in this manner, he will, recalled, the radio-telephone messages were the ordinary garden variety of humans. as a rule, start to gush, hesitatingly at recorded on the Baron's Radiotomatic Not that they do not wish to have themsel- first. Apply more salve plentifully, rubbing plant, on the moon, erected there by him. ves chronicled in due and accepted man- it with the grain, never against it. As a This was done because the moon has prac- ner, no, quite the contrary. They do. And rule the G.M. will now talk freely. All tically no atmosphere to interfere with the they crave for publicity, more so than a that is then necessary is to pull out your weak impulses, after they traveled across stub -nosed society débutante, but they want notebook and take down the precipitate as the sixty odd million intervening miles. the public to believe that they are far above quickly as he talks. Embellish with scraps Recorded on the Radiotomatic plant, the such material things. They wish you to of your own imagination and the chronicle - messages were in turn amplified several think that they are as modest as a spring compound is ready to be sold to the high- thousand times and thence relayed across violet, but down in their innermost inner - est bidding magazine Editor- Gazink -in- the comparatively short distance of 238,000 mostness, they like it if you climb to the Chief. miles, separating the moon from the earth. top of a skyscraper proclaiming their great- Which brings us down to earth, or rather Thus every night I took down the Bar - ness. Of course, they can't do it themsel- away from it. For, if your great man is on's messages and everything ran along like ves, but they like to have it done for them, Baron Münchhausen and if the said Baron clock -work for many days. Münchhausen,

. . . This ray which has the property of disintegrating the ground by breaking up the atoms of the desert sands, has immense inherent powers. The ground, rocks, sands, etc., everything "melts" before it, as snow goes up in steam before an oxyhydrogen flame. . . by some fool chronicler. This induces them has taken it into his head to make the of course, knew exactly whether the mes- to think that they are real modest, but I Planet Mars his abode, how can you chron- sages reached me or not, as he could read- have found out long ago that modesty, like icle him if he don't want to be chronicled, ily check them. The Radiotomatic plant so many another vice is a business, a pretty or rather cant? on the moon, as will be remembered, re- little business at that, carefully studied and What good is it that Baron Münchhausen corded the message, but did not send out carefully plied to fool the public at large. has appointed me as his chief and upper- the amplified message itself till several Now to chronicle the usual species of most chronicler, if the Planet Mars persists hours later, being thus regulated by clock- great man -see first paragraph, line one - in rushing on through space, getting further work. The impulses never were sent out is far from simple, even if you know the away from the earth every day? Of course, till 11 p.m,, Eastern terrestrial time. Thus trick of chronicling. A simple recipe on I can't blame the Baron in the least, for he the Baron, who, of course, had a very fine the subject, therefore, might not be amiss. probably did his best to get his wireless radio plant of his own on Mars, could hear Proceed as follows: messages down to me, but just consider for his own message, as well as I could. For, Obtain a first -class introduction to the a moment what he is up against. if the radio waves were powerful enough G. M. Next mix a fair amount of tact When I first began to take down my to travel from Mars to the moon, they, with a little of the G.M.'s accomplishments nightly reports from Münchhausen, the of course, could travel from the moon to and his work. Mix with a generous quan- Planet Mars was near opposition to the Mars, because the sending plant on the tity of soft salve and carefully cover the earth. It was then about sixty -five mil- moon was even more powerful than the had G.M. with same. The thicker you lay it Copyright by Hugo Gernsback, 1916. All rights first one which Münchhausen on on the better the result. Do not fail to tell reserved. Mars. It is just like an echo. If the voice

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 487 is strong enough to carry from you to the At any rate, I. M. Alier says Münch- asm. The Honorable I. M. Alier seems distant echoing wall, it will travel back enheimer is now seventy million miles to mourn greatly over the lost wavelets just as readily, and you can hear your own away from us, whereas a few months and the interrupted connection. But voice. Thus the Baron heard his own mes- ago he was only fifty million miles away. what would you do? sage every day, just as well as I could. And he furthermore proclaims to all Cheer up, Honorable I. M. Alier. But there came a time when the planet of humanity, and others, that München- What's thirty or forty million miles and Mars, which travels in a vastly wider orbit hauser's wireless waves are no longer a few billion etheric waves between than our earth, became outdistanced by the pow'ful enough to bridge the extra dis- friends? Just think, the Baron might latter. Every day the two planets became tance. Such are the fickle wavelets. be on the Planet Neptune. And that old separated further and b o y is 2,654,001,000 further till finally Baron miles away! Just think Münchhausen's R a d io of it! messages could no longer Well, here's hoping bridge the gap. It must be THE majority of our scientists today are in accord with Lowell's that the Baron will remembered here that the theory of the Martian Canals. That these canals exist, no one de- soon find out a new Baron made his trip in the nies any longer. That they are artificial and that they carry waters brand of waves, to at the shoot at us. And let's Interstellar time of to keep a thirsting planet from perishing seems pretty well established. opposition of the two plan- hope that they are of ets, i.e., when the two were But how such immense waterways, 3,000 miles long and 25 miles wide, the cold variety. Hot but sixty million miles could be constructed has been one of the greatest puzzles to science, (air) waves have a short periodicity! separated from each other. In this instalment is advanced a new and fantastic theory on the But when the last message subject. Will it seem so extravagant one hundred years from now? But everything comes to reached me, Mirs and the an end sooner or later. So earth were already over one evening after I had seventy millions miles resigned myself to the apart-almost twice as far idea that I would not hear distant from each other as when I took Won't stretch a point; just like the in- from Münchhausen, again till the 1918 oppo- down the first message. stallment house when the 269th payment sition, I was suddenly electrified by an un- For days and weeks I waited nightly for is over due. familiar shrill, high -pitched note, corn- the usual 11 p.m. message but not a sound Our reporter suggested to Honorable ing in through my head receivers. The came from my Radio Plant. I installed I. Al. Alier that perhaps the scares could clock had just begun striking the eleventh hyper-sensitive detectors, which became so hour, and I immediately knew that it must sensitive that I could hear the waves sent be the Baron. out by a Ford Magneto at Melbourne, DON'T .111.x.5 THE fECEMBER The whistling note continued for almost Australia! But all to no avail. NUMBER OF THE "E. E." ten seconds, running higher and higher till Of course, I knew that sooner or later it finally went above audibility. Almost the Baron would erect a higher powered The December issue of THE instantly the familiar sepulchral but sym- sending machine on Mars, but it took him ELECTRICAL EXPERIMENTER pathetic voice of Baron Münchhausen broke some months before he finished it. will fairly teem with good things. in my ears and I was overjoyed to hear In the meantime I was a chronicler with- A number of new authors will con- him talk once more! out having anything to chronicle and every- tribute to this Yuletide issue, which "Well, at last! How are you my dear one poked fun at me, as was usual when the editors are striving hard to make Alier? Exhausted from waiting for my something went wrong with my plant. the very best one yet published. message that never carne? I can readily Also, as was their habit, the Yankton There will be a special Xmas fea- symoathize with you, my dear boy, but you papers began to lambast me in their usual ture article, the latest news of the can imagine that it could not have been style. The editors, it seems, had made it scientists, recent happenings in the helped. Bridging seventy million miles by a point, before taking on reporters, to first realm of wireless, and all the usual radio waves is no cinch, as you Americans try them out on me, and thus many rare departments. No matter whether are fond of saying. You will believe me and beauteous literary flowers bloomed in you read THE ELECTRICAL EX- when I tell you that my new Wireless Plant our local press. This is a fair sample taken PERIMENTER front. the viewpoint is a pretty little affair. It takes but a from the Yankton Trench Raider: of a layman or a scientist, you will trifle of 300,000 kilowatts to operate it. A a' full in surely find is cents' worth mere 400,000 horsepower ! But you can rest the December number. PSEUDO SCIENTIST LOSES assured that I will maintain communication "Electric Submarine Camera." By H. with you even when Mars is.in conjunction, Hartman, C.E. that is, when the earth and Mars will be ETHERICAL WAVE -CONNECTION "Baron Miinchhausen" in another ex- at their furthest separation, which is 230 citing adventure. By Hugo Genes - million miles. That is the reason of the Claims Earth and Mars Es- back. enormous energy. Of course, I am not tranged. Are Suing A "Xmas" story thoroly seasoned using the entire 300,000 kilowatts as yet, with volts, ohms and amperes and but I will need the full energy when the ! I for Separation a dash of "construction details" to two planets will be at their furthest sep- tickle the Bugs' literary palate. aration. Professor Flitternix figured it Wuxtra! Wuxtra!! Lost! Wireless "The Marconi $i,000,000 Wireless Waves between Earth and Mars. all out, and he thinks too that we will be Suit Against the United States able to maintain communication when the Anyone finding stray wireless waves Government." By A. Press, B.Sc. sun comes between Mars and the earth. Mars should prómptly return "Reminiscences of an Electrical It is a task to send waves almost around from -Shooter." By H. de Scott. same to 197 Mifflins Manor Road. Trouble and past the sun, which ionizes the ether "The How and Why of Radio Ap- for millions of miles around it, but Fabulous Reward. No 'answers ques- 1 paratus." we Part Two. have fond hopes of maintaining an uninter- tioned! - the Perhaps, readers, you won't be- "Announcement of Results of the rupted interplanetarian radio service in gentle $2,5.00 Interrupter Prize lieve it, but our self- appointed chronicler Contest." spite of the handicap. Hon- "Another Handsome Supplement of the wondrous imagination, the Photo of a IVell-known Radio Sci- But I am certain that my new radio orable I. M. Alier, the illustrous citizen entist" plant, with its many unique innovations, of this Burg, lost his connection with "How fo Build An Electrical Ther- does not interest you half as much as our that dear old friend of his, the venerable mometer." By Samuel Cohen. doings on Mars. And, as the recorder on Baron von Münchenstiner. Our star re- "The Measurement of Capacity." the moon does not hold long and extended porter, who called on Honorable I. M. Also there will appear the prom- messages, I must of necessity be short. Alier yesterday to ascertain why the ised article on "The Revolving Mir- In my last message I spoke about Mart- dear Baron, has of late been so extraor- ror for Determining Spark Charac- ian amusements and our visit to a Mar- dinarily quiet, was informed that the teristics." tian "showhouse." I will now try to ex- earth and Mars were on the "outs" "Experimental Chemistry Course." E plain to you how these wonderful people again. You wouldn't suspect it of such By Albert Wilsdon. build their stupendous canals. I have al- an old married couple, but I. M. Alier "Marvels of Modern Physics." By ready told you how the waters are moved in informs us that every time the fossilized ogres D. Rusk, B.Sc. ffi these canals on Mars, due to the indi- pair get together -opposition he called it rect agency of the sun. I am happy in now -right away, instanter, they begin to .I1 IMW IFIMl l9m^!IIMIfRIMIT!1119' IIIIEITINIT.419n1í" I911V1' T19P1nP1','l'171'8:n1'811'l'Jl'E being able to tell you from personal ex- oppose each other. She goes this way, perience how these ponderous engineering he Foes that Shocking! And they be pieced together endwise and thus feats are undertaken. wont "make up" till 1918. Isn't it make them reach, but he received the You are, of course, well acquainted with scandalous? suggestion coldly and without enthusi- the fact how incredulous your scientists (Continued en ha -e :ni)

www.americanradiohistory.com 488 THE ELECTRICAL EXPERIMENTER November, 1916 When Amateur Wireless Was Young By H. de Scott IT is a far cry from the modern wire- spark, which tho small served our purpose. ground connection for the receiving set less set rated at several hundred kilo- At last the psychological moment arrived was formed by pushing a large size screw- watts and capable of hurtling forth its and everything was tuned up. No polar- driver into the earth, to which a wire was etheric waves over several thousand ized or other type of relay was at hand, attached from the instruments. Happy to miles of space, to the small spark coil wherefore an old burglar alarm magnet relate, the coherer and decoherer behaved excited from a battery, with which Mar- coil, wound to 20 ohms resistance, was quite intellectually for once, and the dots coni and practically all other early radio rigged up with a light, pivoted iron arma- and dashes came tripping in, in apple -pie experimenters worked. ture, so that when attracted by the electro- order, much to the bewilderment of several Looking backward a few years the writer magnet it would close a secondary circuit sidewalk bystanders. well remembers the early reports of Mar- containing a vibrating bell. This was sup- The instruments were working over a coni's great successes in transmitting the posed, according to all documentary evi- distance of about mile on the outskirts now immortal 3 dots -representing the dence on hand, to shake or tap the coherer of the city, but inversely, the crowd was Morse code letter "S "- across the broad filings back into their original state. not very small. A duly uniformed blue - Atlantic from Cornwall, England, to Nova After spending several exciting minutes coat, better known to radio amateurs as a Scotia, Canada. in quieting down the obstreperous coherer "cop" hove in sight. After removing his Ltterest in wireless matters ran high in (not to forget for one moment the always hat and mopping his perspiring brow, occa- those palmy days, when the amateur's aerial lively decoherer), it was finally possible sioned by his recent sprint, he managed to on the roof tops of lofty buildings was a to realize and perceive that wireless trans- bellow out: "Wat ya got there, Bobby ?" rare sight indeed. But, so far as electrical mission was actually taking place. Not over You see I had made up this outfit quite experimenters went (we had no radio ex- a vast distance, like Marconi's, by any complete, even to a wiring diagram of the perimenters in those days), their interest means, as the coherer was not much over instruments which was of course conspicu- might run high or at any old speed they three feet from the spark gap. However, ously shellacked in the lid of the cabinet, liked, but one thing was certain : precious this distance was finally extended to about and to be sure it carried in large size and little information was available in book or 75 feet, after longer brass rods had been thoroughly legible Roman capitals the magazine form for some years to come. placed on the receiving and transmitting word Wireless. That was enough to get Around the year 1900 and in the next instruments to serve as antenna and ground the "cop" thoroughly interested. In fact, few years after that time, the author was capacities. These were old, brass- plated, after he had listened to the spasmodic rav- residing at Trenton, New ings and sputterings of the Jersey, and carried out a coherer and his twin- broth- number of careful experi- er, the decoherer, for a ments on the old coherer minute or two, he flatly re- type radio receiving sets. fused to believe anything The first bit of information less than that the instru- that he remembers reading ment was copying low-down was that endeavoring to racing reports via wireless. explain how to construct a The climax of the matter crude form of coherer. The was that he gave an impera- patent specifications fairly tive order to `close up that teemed, of course, with very contraption and away with elaborate specifications on it." A little incident of this the construction of the im- nature, however, did not proved Marconi type co- deter the present scribe or herer, which was a very his enthusiastic co-experi- beautiful instrument, to be menters in the least. While sure. But, in view of the experiments were being car- fact that no air pumps were ried out with this crude but available and also as there gradually improving radio was considerable doubt as experimental set, a number to the size of the silver and of rather amusing incidents nickel filings to be used in happened from time to time. it and their quantity, little One of these comes to progress could be made mind vividly and happened with this data, at least at thus : One day the spark coil the outset. and key were situated on the floor of our domi- However, a hand-book A Relic of the Author's Early Radio Experimental Days. It Bears Mute Evidence to third which appeared about this the Fact That There Was Such an "Animal" at Any Rate, Even Though Some of the cile, while the innocent time, contained the quite Neighbors Sx ore It Was Nothing but a "Fake." looking receiving cabinet startling information that if was placed on the parlor ta- we were to take two round carbon, motor iron curtain rods "swiped" from the kitchen ble, with its two brass curtain rods pro- brushes. and insert them end to end in a window when mother was out to the corner jecting from either side in their most scien- glass (boiler gauge) tube, and provided, grocery. tific looking manner. A number of the however, that we had a small quantity of After several months of experimenting neighbors were present on this occasion, clean, soft, iron filings between the plugs, with about one thousand and one (includ- including several electrical "sharps," who, that this somewhat doubtful -looking device ing the famous "57 ") kinds of filing mix- in their spare moments, dabbled now and would respond to the etheric waves sent out tures, containing all the know metals and then into the mysteries of the electrical art, by a spark coil discharge. This information some that were apparently unknown, the even so far as to installing their own elec- seemed quite wonderful indeed of itself, writer and his associates finally achieved tric door bells. When everything was and many doubts were expressed by the a certain measure of success. A piece of ready the spark coil was operated and true writer's electrical friends as to whether No. 14 B. &S. gauge, rubber covered copper to nature the receptor responded promptly such a junky contraption would really at- conductor was suspended on a bamboo fish- with a rat -a- tat-tat on the glass coherer tempt to work; in fact, as I recollect it, most ing pole secured to the edge of the roof; tube for every spark. Those present were of the conclusions were that it distinctly the lower end of this crude antenna was quite astounded at the uncanny perform- would not! However, one of these co- taken in through a porcelain tube in the ance and flatly refused to believe that any herers was constructed and the next thing first floor window sash. A 2 -inch spark such mystical animal as a Hertzian Wave was to try out a scheme of pure, etheric coil, which the "general staff" had man- existed in the universe. To cap the cli- wave wireless transmission without any aged to design and construct by this time, max, one of them finally suggested that we ground connection. A spark coil seemed was connected up to the water pipe and close all of the hall doors on every floor, absolutely necessary, but as none was avail- the aerial. The writer arranged to have as he felt sure that the messages came able a medical or shocking coil was pressed one of the family close the key now and down the stairs to each floor and managed, into service. This coil was hooked up with then (mostly then), so as to send out waves somehow or other, to enter each door, so about 10 dry cells, and after fiddling around frcm the improved antenna while he sal- as to propagate themselves in a direction with it and receiving innumerable and un- lied forth with the trick box, containing certain to reach the ever faithful receiving expected shocks, we finally managed to the receiving instruments in order to test instruments. And so it went, much in ac- obtain about 1/32 of an inch spark at the the working range. For a receiving an- cordance with that golden proverb -"Where secondary. We found it necessary to con- tenna, a piece of No. 14 cotton covered Ignorance is Bliss 'tis Folly to be Wise." nect a tin -foil and waxed paper condenser magnet wire was utilized, suspending it Shortly after these experiences the across the vibrator in order to obtain this from a 10 -foot clothes -line prop. The (Continued on page 537)

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 489

721e RADIO LEAGUE HONORARY MEMBERS CAPT. W.H.G. BULLARD. U.S.N. NIKOLA TESLA AMERICA PROF. REGINALD FESSENDEN. DR.LEE DE FOREST. ¡I.Cernsbarle, Manager Activities of the New Britain Radio Club THE New Britain Radio Club are operated by storage batteries. They ary; also a condenser in series with the holds its meetings regularly at also have six pairs of 2,000 ohm 'phones, ground lead to vary the (short) wave the New Brit a i n, Conn., and one pair of 3,500 ohm 'phones. The lengths of incoming stations. Y.M.C.A. every Tuesday eve- club has no official call, but has adopted the In the secondary circuit there is an E. I. ning. The fall season opened on letters "MO." Co., sliding plate condenser in shunt; the the twelfth of September. The roster of members at present numbers 42, but only 30 are shown in the group photograph, as many of 'the members joined after the photograph was taken. All the members of the club have radio sets, of which they indeed may well be proud. Messages are received regularly by many of the members joined after the pllo- lington, Va., and from battleships located far out at sea. Every Tuesday evening the members of the club gather in their room at the Y.M C.A. where discussions are held on various wireless subjects. There is hardly a member owning a station but who can rightly boast of some parts of the outfits that were home -made. Indeed, there are instances where sets in their entirety have been made by certain of the young men whose mechanical ability stood them in good stead. Francis A. Mulvihill, president of the club, has been an untiring worker for the success of the organization. His talks on wireless apparatus and long -distance sending have been highly beneficial to the members. He is one of the oldest operators in New Britain and is, therefore, possessed of a broad knowledge of wireless work. Walter J. Doyle, vice-president, and Al- exander V. Bollerer, secretary, have accomplished much good work and both are well versed in wireless subjects. Alexander V. Bollerer has devoted much of his time to the club, giving lectures on The Members and Officers of the New Britain Radio Club of New Britain, Conn. The Members Have wireless and electrical apparatus, which Excellent Radio Stations at Their Homes and the Club is in a Flourishing Condition were of great interest to the members. A 100 per cent attendance is always the rule The sets shown represent the best of two latter condensers are controlled by the when Mr. Bollerer is scheduled to speak. those owned by the members. The owners two S.P.S.T. switches on the switchboard The club has a 1 K.W. set for sending of these stations are Alexander V. Boller- at the left. purposes. For receiving they have a 4,000 er, Francis Mulvihill, Wesley Parker and Now a word meter loose coupler and two Audions, which Robert Yuon. about the detectors. There are four, one silicon, one galena, one Audi - It will be re- on and a Radioson. These are connected called that Mr. to the loose coupler by a switch system. Bollerer was the There are two D.P.D.T. switches employed, prize winner in the leads from the secondary of the coupler T II E ELECTRICAL running to the center of one, and the cen- E x PE RI 11IEXTER, ter pole of the second switch connected to the June issue. Be- one side of the other; thus allowing the low is a descrip- operator to use any detector simply by a tion of his set. throw of the switch. The sending set of the station com- There are two sets of 'phones in the sta- Brandes' 3,200 prises a Blitzen 1 tion, one ohm "Navy," shown K.W. transformer, on the table, and the other an E.I. Co. 3,000 110 volt rotary ohm "Government" set. By means of the spark gap with an four point switch it is possible to connect oscillation trans- either pair of 'phones to the detect:r. former and suita- The two aerials which are employed at ble condenser, also this station may be used independently of a key with large, each other, or together/as the operator so heavy contacts. desires. One is composed of two wires, 50 The receiving set feet high and 80 feet long, and the other consists of the fol- is 375 feet long and 85 feet high; both are lowing: Long made of phosphor bronze wire. wave loose coup- The station is located in Mr. Bollerer's ler, having a Mur- bedroom and it affords him great pleasure dock variable con- to spend the evenings there, listening to va- country Club Members' Radio Sets. I -Mr. Parker, 2-Mr. Vuon, 3- "Club" Set, denser shunted rious stations working all over the 4 -Mr. Mulvihill (President), 5 -Mr. Bollerer (Secretary). across the second- (Continued on page 5281

www.americanradiohistory.com 490 THE ELECTRICAL EXPERIMENTER November, 1916 DtPARTtt1'-' A 10 K.W. Poulsen Arc Radio Station THE accompanying photograph the meter is used to obtain four different difficult, because courts placed their deci- shows a typical Pou:sen arc ra- wave lengths. Each switch jaw is con- sions upon things demonstrable and could dio station, which is located at nected to a proper number of helix turns speculate as to theories concerning which Central Point, California. by a heavy, insulated metal ribbon. conduc- even authorities did not agree. The de- The transmitting outfit con- tor. The operating key is seen on the left cision read: sists of a 10 k.w. Poulsen arc generator, as of the aerial control switchboard. "Within the limits of an opinion it is, of seen on the left of the switchboard. The The receiving cabinet is seen to the right course, impossible to analyze at length a large insulated knob in front of the arc is of the arc. This is a standard Poulsen mass of experiments, tests and theses, and used for regulating the distance between tikker receiving set, comprising two vari- an infinity of detail necessarily involved in the electrodes. The oscillating circuit, able condenser capacities, which are con- testimony of experts in an art of this kind. trolled by insulat- But if plaintiff's (Marconi Company) the- ing knobs placed ory that its own device and that of de- on top of the cab- fendants (de Forest Company) operate on the sane principle has not been proved, and inet. , The central one operates the I think it has as far as such proof is pos- inductance value sible-at least defendant's theory has not of the tuner, while been demonstrated and, finally, the physical the two lower facts all support plaintiff's claims." ones Judge Mayer complimented Dr. de Forest on the left control on the contributions he had made to sci- the mutual induct- ence. Then the court found for the plain- ance between the tiff, dismissed the counter- claims made by primary and sec- the defendant, but said that there was no ondary coils. The evidence against Dr. de Forest personally. detector employed It is interesting to note that in the word- in this system is a ing of the decision handed down, there is tikker of the im- apparent the idea that the defendants quite perfect contact possibly have an instrument whose mode of type. This con- action involves some, as yet, undemonstra- sists of a wheel ble technical details. Undoubtedly there is with a rough sur- some minute scientific phenomena that oc- curs within the Audion that is not fully faced groove, driv- understood, even by the leading scientists. en at a high speed Several eminent savants have hinted as by an electric mo- much in a number of instances. tor. Two fine gold The Judge admits that the introduction wires gently press of the grid electrode by de Forest was a against this most important advance in the art -a truth groove surface. emphasized by the fact that since its first There are two tik- disclosure tens of thousands of grid Aud- kers used in this ions have been employed the world over, station, one f o r as against a few hundred two -electrode continuous d u t y, lamps -and almost no genuine rectifiers as while the other is disclosed in the original Fleming patent. used for emer- During the course of the trial the de gency. These are Forest Co.'s experts demonstrated that seen on the ex- electrical rectification between the hot and treme right of the cold elements of an Audion played no essential part whatever in the operation. A Typical Poulsen Arc (Undamped Wave) Radio Station Located at Central photograph. T h e Poiit, California. The Small Motors on the Table (right) Dríve the Tkkker" r Bulbs were tested having one, two, and Wheels. connections f o finally three incandescent electrodes -i.e., the tikkers and filament, grid, and anode, all incandescent, which is composed of a high tension con- phones are obtained with the jack plugs heated from separate batteries. The ac- denser located below the switchboard, while seen at the lower side of the cabinet. tions and sensitiveness of these Audions the inductance seen in the upper right - Excellent results have been attained at was unchanged as grid and then anode hand corner, is also used as the aerial helix. this station and it is expected that the com- were brought from cold to the same tem- The antenna radiation ammeter is located pany will enlarge the transmitter. Poulsen perature as the filament. In this state on the small switchboard on the operating arcs have been developed now ranging in either electrode could be made to play the table. The four -contact knife switch below size from 30 to 60 kilowatts. part of "filament," "grid," or "anode"-in- COURT DECLARES AUDION AN years old, it has never been improved upon differently ; thus proving that the rectifica- INFRINGEMENT ON FLEMING by any other discovery for making more tion principle on which the Fleming Valve VALVE. resonant the messages sent through the air. avowedly does and must operate plays no The contention of the Marconi Wireless It was preceded by many other contriv- part whatever in the Audion. Telegraph Company of America that the ances, variously known as the coherer, Dr. Lee de Forest, president of the de de Forest Radio Telephone and Telegraph which was a glass tube filled with filings; Forest Radio Telephone and Telegraph Company had infringed its rights to the the crystal detector, the magnetic detector Company, said that an appeal would he sole use and ownership of the patent cov- and the electrolytic detector invented by taken from Judge Mayer's decision by his ering the Fleming valve detector was sus- Professor Reginald A. Fessenden. company. He added that while the Mar. tained on September twentieth in an opinion In his decision Judge Mayer said that no coni Company also was found to have in written by Judge Julius M. Mayer of the matter what differences of? opinion might fringed, he believed they would not appeal, Federal District Court at New York. Dr. exist between men of science in respect to since the royalties they might be able to John Ambrose Fleming, an English sci- the theories by which they accounted for exact from the de Forest concern for in- entist, invented the detector in 1905 and the movement and action of the unseen fringement of the Fleming valve patent almost immediately thereafter the Marconi forces, concerning which testimony had would be far in excess of the amount they Company obtained the rights to its use. been taken during the trial of the cause, the would be called upon to pay for infringing While the invention is more than ten solution of the issues at bar was not very on the Audion amplifier. The latter, he said,

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 491 was widely used, particularly by the Ameri- NEW WIRELESS TRANSFORMERS. shaped laminated steel tongue which moves can Telephone and Telegraph Company on in and out of the shunted magnetic cir- its trans -continental tines A Western manufacturer has placed on and by amateur the market a new type of wireless trans- cuit, varying the width of the air -gap and wireless operators all over the country, thus yielding any required regulation. The while former for amateur use. the United States Government had The experience which this company has movement is accomplished by means of two bought more than 10,000 of them. The geared wheels that engage either side of infringement decision, had in the wireless field is used to good he explained, lay in advantage in the several new mechanical, the tongue. On the same shaft is also the fact that the Audion amplifier made use placed ail eccentric cam which readily locks of an incandescent electrical and magnetic features which ap- electric bulb, though this pear in the new type as improvements the tongue in any position. The movable was employed in taking practical advantage tongue is graduated so that air -gap can of a principle over the old one. From a mechanical stand- altogether different from that point, the advantages are that all heavy and upon which the Fleming valve was based, though the cumbersome castings have been eliminated latter was the first device em- and the structure is of pressed or stamped bracing the use of an incandescent lamp to sheet steel and brass. This eliminates the be patented. Dr. de Forest said further he possibility of breakage and reduces the that believed the Marconi Company weight approximately 2 per cent. Reduction would not attempt to force discontinuation of the cross section of the frame -work nat- of the Audion device, as, he said, it had urally decreases the sectional area open to proved a far more satisfactory amplifier the eddy currents. This feature, therefore, than the Fleming valve. improves the efficiency of the device. The NEW SHIP RADIO RULES magnetic circuit of this new transformer is IMPOSED. similar to previous designs, in that the ex- New instructions to masters of ships of ternal magnetic shunt is used. There is, the warring nations regarding the radio however, one very important improvement outfits of ships have recently been issued that, instead of varying the entire magnetic by the government authorities as follows: shunt circuit by means of a spring and "Upon arrival inside of the three -mile wing nut as heretofore, the magnetic shunt limit, disconnect aerial. No further use circuit is rigidly and securely held in place, of the only movable portion being a small "V" radio set permitted except in an emergency Wireless Transformerwith Unique Impedance or as stated below. GALLETI WIRELESS TO BE Adjustment. "Current off the radio, both emergency DEVELOPED. and main set. be readily adjusted for any current input "Plant must be available for inspection The Indo- European Telegraph Company, desi red. at any time night or day. Ltd., London, England, states that owing to The primary and secondary windings are "In case repairs to the set are necessary the continued interruption of the company's disposed on opposite legs, the primary be- the radio neutrality inspector must be com- route during the whole of 1915, the actual ing on the lower one. This high tension municated with at once, as in case any seal receipts were confined to local traffic. It coil is extremely well protected mechanic- may be in doubtful condition. has been impossible to make final arrange- ally by a band of heavy metal which cov- "No tampering with seals after they have ments for the reestablishment of the route. ers the outer surface. This band is so been placed, except by a radio neutrality Under the existing arrangements with other constructed as to eliminate corona effects, inspector or duly authorized companies and administrations the com- this in turn reducing the liability of flash- person. pany's receipts not "Sets after clearance may be placed ,in have been prejudicially over to a negligible quantity. The high affected, is condition for use upon arrival at the three - but the directors foresee a diminu- tension coil wound in layers with special mile limit, upon obtaining permission of tion in the receipts for 1916. insulated paper between, the edges of this the collector of the port. On this account the company thinks it paper being folded back, thus preventing "Vessels calling for bunkers whose stay advisable to develop the Galleti wireless the wire from slipping out of place. is less than twenty-four hours are not or- patents and to this end has entered into a There are no high- tension bushings or dinarily required to disconnect, nor is the new combination of interests with the firm cable to this transformer, the metal shield set sealed, but they must not use it for of Creed, Bille and Company, Ltd., of Lon- of the secondary windings forming one sending or listening in." don for the development of the wireless terminal. One valuable feature of this side of the business, for which purpose the transformer is that it is moisture proof. AEROPLANE RADIO TEST. Creed Company will be enlarged. It is the To demonstrate this fact one of these trans- What is regarded by army aviators in intention of the Indo- European Telegraph formers was immersed in water. After be- San Diego as one of the most notable Company to utilize the wireless art in con- ing taken out the faces of high tension achievements in American military aero- nection with its cable and land line system coil were dried with waste and transformer nautics was recorded during the past sum- to span the gaps so long interrupted through when tested under this condition, indicated mer, when Captain Clarence Culver of the the countries at war. no insulation weakness. San Diego aviation school, kept in radio communication with North Island, San NEW HY -TONE RADIO TESTING A condenser and inductance connected Pedro and Dominguez Field in Los An- BUZZER. across the contact points of this buzzer pro- geles during a flight to Santa Monica and The radio experimenter and operator is vide a source of oscillations of constant return.' always on the lookout for a reliable, by- amplitude and constant wave length for The distance covered was approximately note testing buzzer. Here is the latest laboratory and testing purposes. Such an 230 miles and the messages were sent at product of this type, and it is capable of instrument should fill a long -felt want in ten -minute intervals. Lieutenant W. A. operating on one dry cell. It simulates the experimental radio laboratories, as the Robertson, who handled the receiving in- pitch or note of high frequency radio trans- home -made test buzzers either have a struments at the army aviation school, said mitters, and will operate continuously for "frog" tone or else they have a note that that every message was recorded with hours at constant amplitude without chang- passes thru several octaves of the musical amazing clearness. ing its period. It is easily adjusted over a scale every now and then; said now and Captain Culver, whose military aero tract- wide range. It measures 2)4 inches long then being about the time you are ready or was piloted by Sergeant William Ocker, by 14 inches left the North Island aerodrome at 9:30 wide, by 1% o'clock in the morning. Flying at an alti- inches high tude of one and a half miles, the aviators and weighs circled over Los Angeles and then headed but 1 t/a for their destination point, Santa Monica. ounces. The The radio set used by Captain Culver was two pairs of invented by himself. The apparatus, weigh- binding posts ing less than forty pounds, was attached (one pair for to the lower section of the aeroplane, and battery con- the power for transmission was derived nection a n d from a generator that was specially con- one pair for structed and driven by the aeroplane engine. connection High Frequency Buzzer Recently Perfected for Testing Radio Detectors, Besides across the Serving as a Source of High Frequency Oscillations for Measurements. MARCONI SAYS WE'RE SAFE. break) a r e Our wireless friend Marconi says the arranged outside the case so that connec- to balance your wave meter for an accurate United States can't be invaded. Yes, and tions can be made without removing the measurement. there was a time when the wireless tele- cover and no holes need be bored for graph was looked upon as an impossibil- bringing out wires when mounted on a The six state capitals of Australia have ity, Guglielmo, my boy. cabinet or table. been connected by wireless telegraphy.

www.americanradiohistory.com 492 THE ELECTRICAL EXPERIMENTER November, I916

A NEW MAGNETIC AMPLIFIER iron core, and therefore changes the in- (4) As a consequence, it follows from FOR WIRELESS PURPOSES ductance value of the other winding. Should (1) and (2) that, at a temperature of 20 °C. One of the principal functions to be per- the current flow in either winding be suf- the resistance of a wire of standard an- formed in modern radio work, especially ficient to saturate the iron core, it is there- nealed copper of uniform section, one meter where large quantities of power are to be fore rendered practically non -magnetic and in length and weighing one gram, is (1/58) regulated and controlled, as in wireless tele- the inductance of the second winding is re- X 8.89 = 0.15328.... ohm. phony, is that involving amplification. duced to the value it would have, if the Copper Wire Tables. The copper wire coil included only air. When, however, a tables published by the U.S. Bureau of current flows in the other winding which Standards in Circular No. 31 are adopted. lr h IÌI gives a magneto- motive force equal and opposite to the first, the iron core is ren- USING TYPEWRITER SPACE BAR dered magnetic again. As the two divisions TO LEARN CODE. u of the A winding are wound relatively op- The wireless "bug" who during his hours uuin posite to the B winding, the one branch will of sanity is employed in an office can keep lImF1701 ell oppose the ampere turns of B on one -half in fine practice by operating the space bar cycle and the other branch during the suc- on a typewriter, which, because of its sensi- cessive one -half cycle. tive touch and loud after -click, answers 0 //iyhfie9udiet: The opposing ampere turns must be at very well as a substitute for a key. The A- AC ff0o4, least equal to the ampere turns in the wind- beginner also will find this a practical way = B=Ca/m//m.gor = ing B in order to have any flux variation of learning. ' exc/niynirrdvg EE in winding A. Contributed by JOHN T. DWYER. The relations of currents in these wind- Schematic Arrangement of New Magnetic Ampli. ings is substantially the same as between CONNECTING MICROPHONES IN fier Which Operates on a New Principle of Un- the primary and secondary current in a PARALLEL balancing the Magnetic Flux Due to D. C. Ex- citation. transformer, although in this case one is an Dr. Rudolph Goldschmidt has given in alternating and the other a direct current, British patent specification No. 15,915, 1912, Amplifiers represent one of the leading fac- or a current of a different frequency. It is a method of connecting microphones so as tors in modern radio research work. They thus obvious how the current flow in wind- to be worked in parallel satisfactorily. As have many applications indeed, and one of ing A can be regulated in proportion to the it is impossible to make two microphones the latest is the magnetic amplifier, which controlling current in winding B. When that will remain perfectly alike electrically, was recently described before the Institute the magnetic amplifier is used in shunt to it has hitherto been advantageous to use of Radio Engineers by Mr. E. F. W. Alex - a high - frequency alternator, having a solid microphones in series. Goldschmidt's in- anderson, of the General Electric Company. steel rotor, it has the immediate object vention overcomes the difficulty for a pair This scientist, as is well known, has per- of controlling the voltage rather than of microphones by placing in series with formed a vast amount of commendable the current. The aggregate of the con- each microphone, a coil so wound that the research work in the radio field, particularly stant -field alternator and the stationary de- surging of the compensating currents,. on extra high frequency A. C. generators, vice A B has the effect of a machine with which always arise through unequal opera- delivering oscillating currents with a perio- variable field excitation. tion of instruments, is prevented by the dicity of 200,000 cycles per second. As indicated in the diagrams, it is possi- mutual inductive action of the coils. Referring to the accompanying diagrams, ble to connect the amplifier either in series Figs. 1 and 2, we have two magnetic wind- with the alternator or in shunt to the alter- ings A and B related to one another mag- nator. Of these two arrangements, the netically and grouped on a laminated core shunt connection is preferable. Mr. Alex - structure in the peculiar fashion shown, anderson's paper develops in some detail there being a slot left in the central leg of the theory of the ratio of amplification, to- the iron core. It is apparent that there can gether with characteristic curves for series be no direct transformation of energy from and multiple connection of the two alter- one winding to the other for the reason nate current windings with various con- that each turn in the exciting winding B, densers and tuning inductances. Various includes both the positive and the negative arrangements of this amplifier in connec- branches of the flux. produced by the alter- tion with a solid steel rotor, radio fre- nating current winding A, which is con- quency alternator, are .shown, notably those nected in series with the high frequency in series with the alternator and those in alternator or other source of oscillating parallel. Short -circuited condensers are connected to each of the radio frequency coils. A shunt condenser across both coils and their short- circuiting condensers in- The Goldschmidt Scheme for Hooking Up Micro- Another con- phones in Parallel, Where Extra Heavy Currents crease the sensitiveness. Are to be Handled. denser inserted in series with the entire amplifier is employed to obtain linear pro- Fig. A, shows the arrangement where, portionality of amplification and increased and M, are the microphones, and D D,, sensitiveness. The ratio of amplification is are coils wound oppositely on a common found to be proportional to the ratio of core. Equal currents down the coil cancel the frequency of the radio current to that each other's magnetic field, but a circulating of the controlling current. For telephone current would build up a field, and, control the amplification ratio varies from therefore, experience a considerable chok- 100 to 1 up to 350 to 1. The paper de- ing effect. When more than two micro- scribes, with oscillographic curves, the ac- phones are to be connected in parallel tual effects occurring in controlling the they may be caused to work uniformly by out -put of a 75 kilowatt radio frequency pairing them and applying the above alternator. method. CONDUCTIVITY OF COPPER. However, a more advantageous arrange- of Electrical ment is that shown in Fig. B, where coils The American Institute other, and the re- Engineers recommends the following as D, and D, act on each values for standard annealed maining coils are paired similarly. normal Still another method is given in the speci- copper: series with each micro- (1) At a temperature of 20 °C., the re- fication. A coil in annealed phone acts on one and the same secondary sistance of a wire of standard microphones operate un- meter in length and of a uni- current. If the copper one equally, the presence of the secondary tends form section of 1 square millimeter is to choke the circulating current ; if they op- 1/58 ohm = 0.017241....ohm. current tends (2) At a temperature of 20 °C., the erate equally the secondary copper is 8.89 to neutralize the self -inductance of the density of standard annealed methods promise to be of grams per cubic centimeter. coils. These Appearance of 75 K.W. Alexanderson Magnet c the "con- importance in radiotelephony thinks Dr. Amplifier. (3) At a temperature of 20 °C., -known radio scientist. stant mass" temperature coefficient of re- Eccles, the well no voltage in- sistance of standard annealed copper, meas- current. Hence there is Telephones are rapidly displacing tele- duced in the winding B. However, the ured between two potential points rigidly windings A or B fixed to the wire, is 0.00393 = 1/254.45.... graph systems on several important rail- current in either of the roads. influences the permeability of the common per degree centigrade.

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 493 The How and Why of Radio Apparatus Each month we will describe one partic- tism, etc., are practically never fitted with direction of the induced current in the sec- ular instrument used in either the radio a condenser across the vibrator. All spark ondary is opposite to the direction of the transmitting or receiving set, explaining just haw it works, and why. 11'e have received so many requests from new readers asking for such explanations, that we have decided to publish this matter in serial form. In the course of several issues all of the principal transmitting and receiving apparatus will have been covered. The subject for the first paper is the INDUCTION COIL, that much abused and misunder- stood device with which all electrical men FIBRE TUBE are more or less familiar, but which scents PRIMARY to be a complete mystery to the embryo IRON CORE electrician. VIBRATOR

NO. 1 -THE INDUCTION COIL. TIIE induction coil is in general made up of two distinct windings or coils which are usually arranged one over the other, having an annealed iron wire core passing through their center, as shown in Fig. 1. The diagram at Fig. 1 shows in a schematic manner the arrangement of an induction coil designed to produce sparks or high voltages. Usually, at least in wireless work, the primary, or heavy wire winding is placed over the iron wire core. Suitable insulation, consisting of a few layers of SECONDARY insulating cloth or paper, is placed over the iron core preparatory to winding on CONDENSER this coil. After the primary has been completed, which generally consists of two to three layers of comparatively heavy wire, it is carefully insulated by winding over it several layers of insulating cloth; in spark ro coils above one quarter inch rating it is BAT TERN/ preferable to place a hard rubber tube over it. The secondary winding is wound on over this tube, and it is usually somewhat X -Ray View of an Induction Coil, Showing Clearly the Relative Position of the'Core Windings, the shorter in length than the primary. Vibrator and its Condenser. Now, when the primary switch of such a coil is closed, the battery current passes coils, however, are invariably equipped with primary current, during the snake period at such a condenser, which reduces the spark the vibrator. This is in accordance with at the vibrator contacts and also greatly the law of'' Lenz, which states that the di- s P. f/ux fxpaoclibg enhances the intensity of the induced sec- rection of a current produced by electro- ondary current. magnetic induction, is a /ways such as to ,Sec., It is generally considered, and is stated in most text -books on this subject, that the voltage of the current induced in the sec- oryM -> ondary winding will be proportional to the ratio existing between the number of turns of wire in the secondary winding and the Ee number of turns in the primary. This ra- Make frg2 tio holds true for regular alternating cur- Showing Direction of Induced Current in Sec- rent transformers, but it does not hold ex- ondary at "Make" of Interrupter. actly true for ordinary induction coils, as the potential of the secondary induced current is, to a great extent, proportional to the speed of the vibrator interruptions. PFrux Conrroc/ir We may examine the phenomenon taking Sec) place at both the make and break of the

Bi Sec. Oscillograph Curves of Primary and Secondary Core /iron Currents at "Make" and "Break" of Primary Interrupter of Two -inch "Spark" Coil. fig-5 Ee i Screw cause it to oppose the motion by which such How the Secondary Induced Current is Reversed Y in Direction at "Break" of Interrupter. currents were produced. The half wave of secondary current induced at make is not through the first winding on the core and of very high value, and is termed the in- magnetizes it. This attracts the iron arma- verse current. The phenomenon taking ture on the vibrator spring, as shown in Prim. place at the break of the primary circuit Fig. 1, and when this spring breaks contact vibrator or interrupter is exhibited at Fig. with the platinum tipped screw in front of 3. Here the secondary current passes in it, the circuit is opened. At this juncture the same direction as the primary current. there is induced in the secondary winding fig. It is, moreover, of very high instantaneous a very powerful current. The spring -actu- 1 t value and possesses much greater energy ated vibrator returns to its former posi- Circuits of "Spark" Coil, Which Always Have a than the inverse half wave B, shown graph- tion in the fraction of a second and the Condenser Across the Interrupter as Shown. ically in Fig. 4. process is repeated all over again. This may seem at first quite contradic- Small induction coils used for medicinal spark coil vibrator, by referring to Figs. 2 tory to the statement of Lenz's law, but up- purposes, such as the treatment of rheuma- and 3. As will be evident from !Fig. 2, the (Continued on page 523)

www.americanradiohistory.com 494 THE ELECTRICAL EXPERIMENTER November, 1916

CONSTRUCTION OF A EXPERIMENTS WITH A clear. I heard an amateur in Michigan REINFORCED WOOD MAST. RADIOSON DETECTOR. with a 1 K.W. set; everything on the coast To the amateur desiring to raise his aerial The latest type of sealed point detector, "drums in" at night. to a greater height than his present single termed by its makers the Radioson, has Contributed by FRANK M. KUSS. stick mast will permit, the following con- been the subject of very little experiment- struction of a reinforced mast or tower is ing. This detector works very well and is LONG SPARKS AND QUENCHING unusually sensitive, yet too many amateurs TUBES. fail to realize the broad field of research Max Wein has shown that quenched opened to them by this instrument. They spark excitation can be affected by aid of merely mount it on their receiving set, long sparks, if the coupling between the marvel at its efficiency and naturally do not try to improve its operation, thinking it perfect. The author recently conducted a series of experiments that rendered the instrument even more sensitive and may be of interest to owners of similar detectors. These experiments were conducted on a cartridge that had been in use for a year. The first noticeable detail of the Radioson was the fact that it was impossible to get at the sealed -in platinum point and steps were taken to render this possible. Refer- ring to Fig. A, the glass was carefully filed at the point X, and a light tap served to part the glass tube. The next step was to obtain a rubber A New System of Utilizing Long Sparks in Radio cork, drill a hole through it to pass the up- Involves Passing Them Thru Quenching per electrode, and by using this cork as a Tubes. coupling the entire cartridge was re-as- primary and secondary circuits is nicely ad- sembled. justed, states Dr. Eccles in his work, Wire- A new stand was constructed in A Good Idea for Bracing Aerial Masts and In as shown less Telegraphy and Telephony Hand -book. expensive to Apply. Fig. A base of suitable size was used Sparks between 0.5 and 2.0 cm. can be used; offered. It may be built to any reasonable and an upright was mounted thereon. A silver electrodes are best, magnesium worst, height and can be extended to a greater holder for the cartridge was fashioned from as regards the effective value of the secon- height at any time the amateur chooses. a strip of wood; two clips were used to dary oscillations. But the coupling has to The mast A (Fig. 1) is composed of two clamp the cartridge. The holder was piv be loose, and therefore the building -up strips of wood % "x3 "x12" nailed together oted to the upright, with flexible cords run period is about as long as the decay period, as shown in Fig. 2, forming a hollow box with impure oscillations as a result. These with the exception of blocks B (Figs. 2 and defects may be partially removed by mul- 3) placed every three feet within the mast to tiple gaps and immersion in hydrogen, but keep it square. In starting the construction the use of quenching tubes is much superior. of the mast, boards of the above dimen- A quenching tube is merely a short (evac- sions, three feet, six feet and nine feet long uated) Geissler tube. Several types are are nailed together as s:.own in Fig. 3, and shown in the illustration. The best pres- the construction continued with twelve -foot sure is between 0.1 and 1 mm. of mercury, boards until the mast is of the desired and hydrogen gives rather better quenching length. It is then finished with shorter than air. The best metal for the electrodes pieces as above. This brings a single joint is silver. The tube is placed in the primary at each three feet of the mast. circuit, near the ordinary spark gap. With C 1) one inch Method of Mounting and Connecting the Radio - a primary circuit, comprising a condenser The braces (Fig. are son Detector for Improved Results. square by one and one -half feet long and of 0.86 x 103 M. F. and an inductance of may be either solid or of box construction. 40,000 e.m., together with a nearly equal ning to the clips. The sketch shows the the coupling was Four are nailed to the mast every three device very clearly and will facilitate the secondary circuit, critical 10 per change has feet and wired as shown in the diagram construction. about cent. Capacity with doubled iron wires which are twisted little effect on efficiency, which is high. With this device it was possible to place with a spark gap of 2.5 cm., between until tight. The wires are attached to the the cartridge at any angle desired. With Thus ends of the braces with nails or screw -eyes. silver discs 5 -cm. diameter and a quench- the detector in the circuit and signals corn- with silver electrodes, an efficiency The entire tower should be given a coat of ing in, the knob was slowly turned; the sig- ing tube white lead paint for a neat appearance and once but of 84 per cent was reached, the secondary nal strength does not change at R.M.S. being 4.4 amperes. Wien to prevent the wires from rusting. It when it reaches a certain point the inten- current should be guyed by at least three guy wires has shown that this method of shock ex- sity of the signals suddenly increase to an easily and effectively carried spaced 120 degrees apart. almost unimaginable extent. citation can be 1 K.W. Contributed by H. W. OFFINS. The writer has since determined that this out with power inputs of about no INDUCTIVE BUZZER TEST FOR angle varies with different cartridges, USEFUL SWITCH WRINKLE. doubt due to slight irregularities in the Here is a plan for fastening wire to DETECTOR. glass around the sealed -in point. The ac- Wind a layer of wire around a cardboard switches on loose couplers that I have tion may be due to some capillary action found convenient. tube about 1 inch in diameter and 3 inches between the glass and the hydrogen gas, long. Connect the wire to the adjustment F is the panel. A is a brass or copper since bubbles do not come off as frequently plate fastened to panel by screws C and screw of the buzzer as shown in the illus- as before. With such an arrangement it tration. Through the center of the tube C'. D is a nut on the screw from the is possible to tune out weak interfering sta- knob and is fastened by a drop of solder layer wre tions by merely turning the knob to the Torec.oOL+ proper position. ,/ The final experiment was to provide for iIlIII IIIIIIIIIIIIiIIII IIIÌIIIIIIIIIIIIII i some means of agitating the liquid. To do 1lulllllllllllll_II this, short lengths of platinum wire were 1Tli f forced through holes in the cork as shown >------in Fig. B, flexible cords being attached to The circuit used is > BOf= Buzzer the protruding ends. also given for the benefit of those not acquainted with this little "kink.' The ex e EE Simple Design of Cabinet Switch Having no Wires tending seal of the cartridge was broken to Work Loose. Exciting the Aerial with Buzzer -test Current by off to allow any gas formed to escape. Induction from a Coil as Shown. The results with a common Radioson so that it cannot work loose. The wire run the wire from the aerial. The buzzer may be excellent, but the signals obtained connection is soldered on the plate at some signal will be heard in the receiver dis- with these improvements are astounding. corner as at E. This way there is no tinctly and loudly if the detector is adjusted With a 65 foot aerial, 55 feet high, eight strain on the wire and the switch will correctly. wires, loose coupler, variables, 2,000 ohm never work loose. Contributed by ALFRED O'HARA. 'phones, NAR and NAX come in loud and Contributed by HOWARD BIERLY.

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 495

A "SECRET" CODE CHART. Radiation Current In Radio Antennae Now that there are so many amateurs By C. L. Whitney in the wireless field, it is often found very convenient to use a secret code for any Many amateurs have often been puzzled transformer input, and we obtained 6 am- communication which it is desired to keep over this question : "flow many watts do peres instead of 5, we would radiate 142 more or less private. I radiate ?" Of course we know that we plus watts; our set would then be nearly The following described "secret" code cannot take the approximate voltage (in 15% efficient. 'chart has the great advantage of contain- the aerial) and the amperage, and multiply We can increase the radiated power by to get the watts; for example: We have increasing the height of the aerial. Thus say, 10,000 volts at the antenna lead, and if our aerial was 200 feet high instead of our hot -wire ammeter reads 5 amperes. 100 feet and the hot -wire ammeter reading Now if we calculate the watts by the ordin- remained the same (5 amperes) we would ary method we would have 50,000 watts or radiate 4 times as much as before or about 50 kilowatts, which we know cannot be 375 watts. correct as we only have a 1 K.W. trans- Radiation may also be increased by in- mitting set. We can never get over 100% creasing the number of wires in the flat -top, 0 ópo©op0 efficiency, while if we did get 50 K.W. in but the most effective way to increase the .Secret the aerial, we would be getting 5000% ef- radiation (and incidently the range of the Code oChart ficiency, or the aerial current would be 50 station) is to increase the height of the main times as much as we draw in the trans- aerial. We could build an aerial say 100 former. feet long, at a distance of about 10 feet Many of us have not been able to figure from the ground, and when we connect our O out, even approximately, what our radia- transmitting set to this. the hot -wire am- tion really is, and the author hopes that the meter will show a higher reading than when following formulae will prove of value: the set was connected to a high aerial. óce can 1G The watts radiated from a flat -top aerial However, by the above formulae we may be found from the equation: readily see that the power radiated (watts; 4©Q s not amperes alone) is not high, and natur- P =1578.2 zas ally the distance we can transmit is also a curtailed very much. Where :- P =power radiated in watts. It is now plain why in some cases one To Operate This Secret Code Chart, Rotate the feet). Inner Disc Until the Desired Letter Is Opposite h= height of aerial (in station (call this station No. 1) radiates A= length emitted wave the Letter on the Outer Disc to Be Sent by Code of (in say, 8 amperes, and has a range of say, 200 feet) miles: while another station (call this sta- ing many different combinations which may a=ampercs, measured by hot - as tion No. 2) radiates say, 5 amperes and be easily deciphered. wire ammeter in aerial circuit. disks are cut from card- works 300 miles as easily as station No. 1 Two circular is the antenna This formula used where works 200. If you will notice carefully just board, one about 1% inches less in diam- capacity is mostly in the flat -top. For ex- how each station's aerial is built and how eter than the other. The circumference of ample: the leads run (if parallel to iron masts, each is then divided into 36 equal parts and 100 Supposing we have a flat -top aerial stacks, etc., in case of a station on a ship) radial lines are drawn through these points. feet high with leads brought down from you will find that the aerial of station No. Holes are then cut through the centers of the center. Our wave -length is, say, 600 the disks and the disks put together and 1 is either low, or that the leads run paral- meters or approximately 2,000 feet. The lel to some grounded object and therefore fastened loosely, with an "easy rivet," so hot -wire ammeter reads 5 amperes. although 8 amperes leaves the station. much that the disks may be rotated independ- s of it is lost to the grounded objects. Again ently. Then:-P = 1578.2 Z 000' 5s the aerial may be low and thus the WATTS Letters are marked on the circumference radiated is low, although the hot -wire am- of the disks in the spaces, as indicated in or P= 1578.2 25 - 88.6375 watts. meter shows a high reading. The prac- the accompanying illustration. 41000,0000 tice of using hot -wire ammeter readings To use: Rotate the inner disk to the com- Therefore, with a flat -top aerial 100 feet to compare two or more stations is very bination desired. Then send the letter on high on 600 meter wave -length we are radi- misleading, as becomes apparent. the outer disk, opposite the letter which ating approximately 88 watts. forms the word on the inner disk. This The author has tested a' United -Marconi The watts radiated from a vertical aerial gives the combination. Then substitute the 1 set practically 15% ef- is given by the formula: K.W. which was letters on the outer disk for the adjacent s ficient (from transformer input to aerial), letters on the inner disk. Each card gives 150 watts in P= 640 -as radiating about the aerial, and 36 different combinations. Various cards as with which it was possible to work from may be made with the letters in different This formula is applied in the same way as 400 to 500 miles in the daytime with the sun sequence. the first. shining, although the aerial was only about Contributed by 90 feet above the water. This set was in- Now we can calculate the power radiated RAYMOND S. SUTCLIFFE. in still another way, as long as we know the stalled on an Army Transport which took radiation resistance of the aerial, and the part in the operations during the 1914 Mexi- SIMPLE DETECTOR number of amperes. can trouble. SHUNT. P=Ra A2 Many amateurs are bothered by the de- Where; -Ra= radiation resistance in ohms. A HINT FOR COPYING N A A tector being knocked out while sending. A= Amperes, measured by hot - WEATHER REPORTS. This is very annoying and can be remedied wire ammeter in ground or In connection with copying N A A by this device. Referring to the illustra- aerial lead. Weather Reports I have memorized the tion, A, represents the sending key; B, To find the approximate radiation resist- following signs which aid greatly in fiber piece, 2 inches long, ih inch wide. ance (Ra) of a flat -top aerial we use this taking the reports down, especially when formula: they are sent fast. After trying them s out a few nights, I found it very easy 1600 i =Ra (in ohms) to get the reports complete, as these arc a the more com- Where :-h=height of aerial form of shorthand for (in feet) monly used words in the reports. Here a =length of emitted wave '(in feet). they are: A East > From e Now compare your transformer input North Northeast Al West < To ' (in watts) with your aerial radiation. (in Northwest in Moderate s And watts), and you will see that radio appa- - South V Winds \ Great Lakes D ratus is not so efficient as many have been Southeast V1 Atlantic I Pacific II led to believe. As mentioned before, we Southwest 1V Coast o have a 1 K.W. set which radiates 5 am- Auxiliary Contact Arranged on Key to "Shunt" peres These words occur most frequently Radió Detector While Transmitting a message in the aerial (which is 100 feet high). in every report, for instance: 1 K.W. =1,000 watts. (This is the trans- Al c D drilled with 2 hqles as observed; C, con- former input.) Northeast winds from Great Lakes at 30 tact screw from old key; a bottom contact According to our calculations the radia- o mounted on fiber block; E, detector. This tion is 88.6 watts. It is easily seen that the miles an hour to Florida coast. device short -circuits the detector during set is only 8.8% efficient (from power in- After a few days practice it comes sending. put to aerial). If we improved our station easier than to write them down. Contributed by in some way, other than by raising the Contributed by FRANK TALONE. WARNER N. CROSBY.

www.americanradiohistory.com 496 THE ELECTRICAL EXPERIMENTER November, 1916 THE 2N5TRUQTR000 000000t=1

A Wireless "Hound" That Dogs Your Foot -Steps By F. A. Steinbrook OW would you like to have an elec- six selections. When the rotator is halted stop, 4, closing a circuit to the electrical tric "pup" that will follow you around at stop, 6, this is the neutral position. If horn, 10, adjusted to give a growling note H like all faithful quadrupeds of the the light rays are flashed on the selenium as if it wanted more frankfurters. genus "hunt." Well, here's how: cell and immediately released, the rotator A fifth flash and the rotator moves to stop, 5, closing a circuit to the automatic LAMPS flasher, 7. This flasher opens and closes SELENIUM the circuit to the electric lights, 19, or CELL "eyes" of the dog, causing them to flash bn and off. This continues until the sixth flash of the light, when the "dog" becomes perfectly neutral. (The flasher, 7, can be made from the striking part of an old clock.) A pointer connected to the rotator by a rod, may extend to the top of the dog's carcase. Numbers from 1 to 6 are placed on top of the dog, corresponding with the CLOCK respective positions of the selector. -" 4 ¡ WORKS i When the selective device is at point, 4, the is at 4, ELECTRIC SPRING pointer on top of the dog etc. HORN MOTOR This enables the dog's master to determine exactly where the rotator is at any time, and to aid in the selecting. CHAIN OR BELT DRIVE By flashing the light rays on the selen- IN LEG ium cell, one may watch the pointer and select any of the desired stops. If it is desired to have the dog to go to the right, the light rays must be flashed on the cell until the pointer is at index, 3. The rotator may be stopped at point 1, then at point 3, or 4, as desired. When the dog is to be controlled wire - lessly, the switch, 4, is turned to point, 2. STEERING; This places the coherer in circuit with the WHEEL polarized relay, 3. A small aerial is placed on top of the dog, and a copper plate on the side serves as a capacity ground. By using an ordinary radio sending set, selections may be readily made; each time the key of the sending outfit is depressed the selective device works in the same manner as with the use of the selenium cell and flashlight. To make a real "doggone hound" out

Here we Have the Experimenters' Delight -a Wireless Hound" That Will Obey Your Most Arden Desires. It Can Be Operated by a Flash -light Ray Thrown on a Selenium Cell or by Wireless Waves Actuating a Coherer and Relay.

To make this faithful "canine" we will turns to stop 1; the pressure of the rotator first require a selenium cell, 2. It is placed against stop, 1, closes a circuit and starts on top of the electric dog, so it becomes the motor, 5. This in turn starts the dog in easy to focus light rays on it at any de- a forward direction. (The driving arrange- sired time. When rays of light are focused ment is shown quite fully in the drawing.) on the selenium cell, making it a conductor When the rotator is in this position, it of electricity, it closes the circuit to the makes another contact with the contact polarized relay, 3. In turn, this relay closes rings, 11; this also closes the circuit to the the circuit to the selective device, 1. A motor, and the motor is kept in circuit two point switch, 4, is placed in the circuit; until the rotator reaches stop 5. Then the when the switch blade is placed on point circuit to the motor is opened, when his No. 1, the selenium cell is in circuit; when riverence, the "pup," stops his forward placed on point No. 2, the coherer is in cir- peregrinations. cuit. (The selective device was made from A second flash of the light rays on the a phonograph works.) selenium cell, and the rotator moves again The polarized relay 3, closes the circuit and halts at stop, 2, closing the circuit to to the magnet 12, on the selective device, the solenoid, 9; this turns the wheel, 21, which releases the rotator, 22, allowing it to the left, and the dog moves in the same to rotate to the right as long as the circuit direction. is closed. There are six stops on the selec- A third flash of the light rays on the cell AMongrel" Wireless Pup which may Have his tive device. When the circuit to the selec- and the rotator moves to stop, 3, closing Works Encased in a Common Soap Box. tive device is opened, by removing the light the circuit to the solenoid, 8. This has rays from the selenium cell, the magnet, 12, the effect of turning the dog to the right. of this all -fired contraption one should pro- releases and the rotator stops at one of the A fourth flash and the rotator moves to cure Some papier -maché and build up a

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 499

carcase on a wooden frame. The legs, INVISIBLE PHOTOGRAPHS. mado and the great advantage of this var- head and tail can be easily formed in a In time of war particularly, when certain nish is that it has a very high insulating rough manner of light sticks, well nailed information should be rigorously kept sec- property, and when properly prepared, has a and screwed. The legs do not move. Lo- ret, even from subordinates in the same glossy finish, on coils for instance, that comotion is effected through the two chain service, it may be useful for government quite resembles glass. Another good point: or belt- driven rubber-tired wheels on the officials, military commanders and others to it is moisture- proof, flexible and dries very front feet. The animal is steered about by have a method of keeping copies of plans, quickly, an important factor. In short, it is the electro- magnetically controlled rear documents, photographs, etc., in their pos- a very useful and handy proparation in any laboratory or experimental workshop. Formula. Dorn adjusted to 11111 ;1i11umwi Dr/rmgmotor lit. -Procure a quantity of film trim- ! S growl /tee o dog mings, which any obliging photographer Dellor cnom arm /° will let you have. 2d.- Remove gelatine coating on film trimmings by washing them in hot water

I /forme / to which soap may be added. gear 3d. -When dry, dissolve films in the fol- Je/eclive Me lowing solution: vdevice Acetone, 2 oz. Selenium cell mounted !mlopofdo Amyl Acetate, 2 oz. Add the film trimmings until you have Wiled reBly the right constituency to suit the work. Contributed by ARTHUR PELLETIER. LAMP BANK SWITCHES. A wiring diagram is shown at Fig. 1, by which the number of lamps connected in multiple in a lamp -bank is changed in uni- 4 form steps by means of a very simple i -_ switch-board. It may also be used to change the number of plates in a "fixed" Rope/ /a star/ condenser. c/och-yorh By manipulating the switches A, B and C, the capacities, of which there Nouher are four, each in successive step twice the opyrrvp/e one before e., i it (i. if the first is -cfne, the /°rgrd next -two, the third -four, and so on) can AubDer tired / /B either be taken separately or added, so that IIVIIII rvheel áenia/movrri/edanalog. fourteen capacities are obtained in steps r SI a equal to the first capacity value. The Wiring Diagram for Wireless "Hound," Showing Relation of Propelling Motor, Radio Apparatus, points on the switch -board are marked with Selenium Cell, Steering Mechanism, Eye Lamps and Flasher and "Growl" Producer. their capacities as shown and thus it is a very simple matter to obtain the desired wheel, which should be painted and con- session in such a manner that they are or- capacity. structed to be as inconspicuous as possible. dinarily invisible, but can be revealed by a (By connecting a single point switch, A crude electric dog is readily made from simple process when required. extra, to capacity No. 1, it can also be a soap -box and three wheels as shown in After trying numerous printing -papers added to the sum total of all.) one of the illustrations herewith. The and bleaching- baths, a writer in Progresso Diagram No. 2, is a multi -point switch, wooden frame of the dog may be covered Fotografico has come to the conclusion that by which the number of lamps or other ap- with a mixture of shellac and paper, with the least visible image is given by the thin paratusi connected in multiple, is changed a little care. Paper pulp works best for sepia paper of commerce. It is exposed by simply turning a knurled knob. Each this purpose. rapidly to direct light, developed in ordi- lamp is connected by one pole to a spring nary water, then treated with a 2 -per cent. contact point, which A LATHE. is connected in suc- SMALL WINDING hyposulphite solution, and washed for a cession to the others by the copper plate Every experimenter wishes a small lathe few minutes. The images obtained are not shown in diagram A, which is to turn pulleys or wheels out wood or to revolved of very rich in half- tones, but this is not of over them by means of the knob. wind magnet coils. One that can be run great importance for practical purposes. It may be placed behind a panel as shown from a small emery wheel motor or even a When the prints are placed in a solution in diagram B, making it much neater. Dia- sewing machine, can be made from two old containing, per liter, 10 grains of copper magneto frames such as used in telephones. sulphate, 20 grams of potassium bromide, -B - In Fig. 1, A is magneto frame with the and 5 drops of hydrochloric acii, the image /vingp armature removed; B is a second frame disappears instantly, and, after washing, one Hero / /ole with rod R in place of armature and sold- may dry the print, upon which nothing is ered or screwed to frame B. Rod R passes visible. If the precaution is taken to plunge through two standards M M', with set screw the print in a weak bath of potassium bro- in M to hold tail piece of B in position. mide, even exposure to light does not cause 1, JPiingpom/ o The face plate C can be made by soldering any reappearance of the image. 1 m a piece of brass to a % " -24 nut, which is ///i-e ,fpringaants -59 2- CELLULOID VARNISH. For coating high frequency apparatus, var- toopP nishing loose coupler tubes and coils, mend- ing broken celluloid ar- XzzDzO ticles, making enamel wire. or lacquering exposed metal parts of receiving apparatus. C celluloid varnish is just Simple Winding Lathe Constructed from Two Magneto Frames, Assuring the thing. It is easily the Builder of Having Good Bearings at Least. /- ,Nain /ile usually the thread of the shaft D. Shaft When pulleys are turned the wood can be D' has the large gear cut off and the shaft screwed to the face plate. The triple step Effective Switching Arrangements for Lamp is tapered Banks, Permitting Any Number of Lamps to Be to a point. On this shaft is a pulley P was turned that way. When wind- spring with collar and set screw. Connected in Parallel as Desired. ing coils the core can sometimes be held by Fig. 2 shows clearly the end view of B. gram C, shows a spring contact point in inserting a piece rubber between TT are two pieces of flat iron to form a of face detail. These should be mounted as nearly track. NN are two pieces of iron screwed plate and core. The spring on shaft D in the same plane as possible and should on the sides of the magneto frame to form tends to take up any lost motion. he of moderate strength only. a slide. Contributed by ARTHUR A. REEVE. Contributed by JESSE O. HOWELL.

www.americanradiohistory.com 498 THE ELECTRICAL EXPERIMENTER November, 1916

DARK ROOM LAMP depending upon the range of voltage want- A BATH TUB ALARM. AND PRINTING BOX. ed. In this case they were taken out every The hook at the top of the cane -shaped Referring to the illustration herewith, A twenty -four turns, giving 3 volt steps. wooden strip is hung over the side of the is a wooden box 8 by 71/4 by 51/4 inches, The taps are soldered and taped to the bath tub and the water turned on. The outside dimensions; B is a printing frame winding and the wire is run back over float is made in such a manner that when (postcard size) screwed to the box over the winding to holes in the fiber heads. the water rises as high as the float the hole cut in box which corresponds in size Each layer of wire should be shellacked. water will lift the float up until contact A to the opening in printing frame; C is a Between the secondary and primary a touches contact B, thereby closing the cir- layer of tape and several layers of shellacked paper are placed. The primary (110 volt A.C. winding) should consist of 900 turns of No. 24 S.C.C. wire, 450 turns on each leg. This will require about one pound of wire. The wire should be wound very smoothly and evenly, and each layer should be separated by a layer of shellacked paper. Be sure to wind the two legs in the same direction. Outside the last layer of wire on each leg place a layer of tape and shellac well. The yoke pieces of the core should now be fitted into place. Place one piece between the laminations of the other leg and so on until all the spaces are filled. The windings should now be An Amateur connected, the Dark -Room Lamp and Printing parts of each winding on the two legs be- Removable Home -Made Electric Alarm for Bath Cabinet of Small Cost. Contains Red and White Tubs. Closes Bulbs. ing connected in series as shown in the Rising Float Bell Circuit. drawing. cuit and ringing the bell. Of course a bat- 25 -watt Tungsten lamp in socket; D is a A good mounting for the transformer is 5- candlepower red bulb in a candelabra tery is connected to the two binding posts shown in the drawing. The windings are C and D. These posts may be placed in socket; E is a push switch off an automo- left out for the sake of clearness. The bile dash; F are blocks to hold a ground a convenient position on the wood strip. taps from the secondary may either be con- This piece of apparatus is intended to lass 4% by CPA inches; G is the opening nected to binding posts or some sort of in front fitted with a yellow and a red give an alarm when the water in the bath switch, as the experimenter may elect. tub attains a certain height. For instance, lass, the latter being removable, while H Contributed by ADRIAN SCHADE. is a cord and wall plug. suppose Mr. Jones wants to take a bath This outfit was made of material which and also a shave. He puts the bath tub I had aroùnd the house and gives the same UNIQUE ELECTRICAL WINDOW alarm in place and connects up the bat- results as a $7.50 outfit purchased from a ATTRACTION. tery; then he turns on the water. He goes into another room and starts to shave. dealer. As everyone knows, the moving window Contributed by A. E. WILSON. While he is shaving he hears the bell on attraction draws more of a crowd than the alarm ring, thereby notifying him that any stationary display A 30 VOLT LABORATORY STEP - of goods, and if this the tub is full. He can then turn the water DOWN TRANSFORMER. attraction has the element of mystery in off and keep the tub from overflowing. it the crowd will be larger. The Electrical Contributed by This transformer operates on 60 cycle, Review gives 110 volts A.C. and gives from 3 to 30 the construction of one of PHILIP MANDELBERG. these attractions, which is volts in 3 volt steps. It is very suitable especially good for an electrical shop or booth. It consists To polish woodwork: Apply several for use in a home laboratory. of an opal -lamp The core is in the shape of a hollow rec- arc globe practically full coats of varnish, rubbing down each coat tangle, 6,4 inches by 4% inches outside of water in which an incandescent lamp with linseed oil and powdered pumice stone. dimensions, being composed of pieces of floats "tip up." At short intervals the lamp lights up brilliantly and at the same tached lamp is pulled down toward the bolt transformer iron, 1% inches by 5 inches time disappears and 1% inches by 3 inches, stacked in the or ducks under the water head. A sheet of tinfoil over the latter in a very mysterious way. After a few prevents actual magnetic contact and stick- usual way so as to make the core 1,4 inches seconds it thick when compressed. This will require again bobs up and its light prac- ing due to residual magnetism when the of a pipe tically fades out. This is repeated indefi- current is again cut down to its low value. the purchase piece of "stove nitely. is iron" 2 feet wide and 4'4 feet long. After The only apparent, though mis- The cabinet on which the globe placed leading, explanation seems to lie in some and the wires really leading to the coil and being stacked the legs of the core are taped wires with with three layers of insulating tape and bared ends projecting over the lamp are covered by a cloth, leaving very edge of the globe, thus giving the idea conspicuous, however, the wires on the then the yoke pieces are pulled out, leaving the the legs intact. that action of the lamp was due to outside of the globe to the antenna -like wireless or inductive influence. arouse no Four fiber heads are made 2 }/ inches ends. This little display will The incidentally, will stim- square, with a 1,4 inch square hole in the accompanying illustration will give end of inquiries and, the details so that anyone interested can construct one. Noter /eve/ s ,fanstM,Glfd Yate A field coil from an old dismantled motor is placed in a box and barer/re t1 11II1 ,1 term/no/s within is put an iron core; a small iron 3i' pulley that happened to fit the coil was used for this one. An iron bolt is pul through the box cover into the center of /roll trine the core and the wires feeding the lam/ Spira/ run through the cover alongside the bolt Core assembled and Insulation Min toped jec The lamp is connected in series with the coil; the wires are soldered to the lamp base and well protected by rubber tape. :W.,.K,`.y'äaT-,ti...., tops To seal the bottom of the globe use a rubber sheet with a layer of sealing compound filled in; an electric soldering iron is used óreYm to work the compound well around the edge and about the bolt head to make a leg wounds loped Primasee water -tight seal. Fasten an iron wire with Details and Hook-Up for Small Step -Down Trans- the lower part in a spiral form to the %f/os her /rot core EE former of Closed Core Type. lamp base by a loop over the tape. This The Lighted Lamp Bobs Up and Down Very wire is of just the right weight to keep Mysteriously, Due to Action of the Electromagnet. center. These are slipped over the ends the lamp about half submerged when the of the legs. current is off. Connect into the circuit a ulate the sales of all kinds of electrical The low voltage secondary is wound Thermo -blink flasher, which periodically goods, which, of course, is its prime object. first. This consists of 240 turns of No. cuts the current in the lamp and coil cir- Moreover, it is a novelty that will appeal 14 D.C.C. wire, 120 turns on each leg. This cuit down to a low value. As the current to parlor entertainers and rising young will require about two pounds of wire. is restored to full value the coil is ener- Edisons who want to impress their doting Taps may be taken out as often as desired, gized and the iron spiral with the at- parents with their marvelous genius.

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMETNER 499

HIGH -FREQUENCY RESONATOR and the current automatically cuts itself off preserve the finish, oil on a cloth rubbed FOR SPARK COILS. when a supply of chlorine is made. The over the polished surface, protects the brass Procure a mailing tube S 9 inches long outfit can be adjusted to feed as little gas from damp weather making the work last- by 2 inches in diameter and wind with as required, the supply and discharge being ing. No. 34 wire leaving % inch space at the regulated by the gas pressure in the gen- Contributed by JOHN A. COWING. top and bottom. Next take a straight, erator. The bottle, usually 1 gal. in size, short piece of No. 14 copper wire, filed to is filled with a saturated solution of salt A REMARKABLE IMPROVEMENT water, and is inverted over the glass or IN ELECTRIC BELLS. earthenware crock, which a gasket makes By W. Rademakcr. air -tight. The glass tube shown, extends A new interrupter device, for bells and to within approximately 3 inches of the the like, which is practical and absolutely bottom of the crock. reliable under all conditions, has been pat- The tube measures 3 inches in diameter ented lately. This interrupter represents and is sealed into the top so as to be gas- a radical departure from all previous de- tight. On an iron rod is clamped the posi- vices. The chief object in view with this tive carbon, which is connected in series invention is to do away with exposed con- with a 32 -cp. incandescent lamp. In the tacts, thereby rendering the device posi- U -bend discharge pipe is a valve which is tively water, rust, dust, ice, insect and fool- adjusted for the proper discharge. When proof. The contacts working in an her- the bottle is filled with the saturated salt metically sealed, air -tight chamber cannot solution, and the current is turned on, oxydize or corrode. Therefore, an electric chlorine gas is formed inside the 3 -inch bell has been created which works without glass tube. This gas drives the solution the principal source of trouble so frequently down into the tube until the circuit is in- experienced with bells now -the breaker - terrupted at the bottom of the electrode. post or contact screw. If the valve in the outlet pipe is closed or The construction and working of the de- set for a small discharge, this gas will con- vice is very simple. As will be seen in the dense, and allow the solution to rise in the accompanying illustration a cylindrical piece tube, re- establishing the circuit and so gen- of metal lias a hole drilled into it at erating more chlorine. As the chlorine is each end. A thin sheet- silver bushing is new solu- inserted into each of these holes which rest An Oudin High Frequency Coil for Use on Smal discharged through the U -tube, Spark Coils. Many Interesting Experiments Can tion is allowed to feed down from the bot- freely upon two small silver points, :tak- Be Performed with This Apparatus That Open Up tle, and the apparatus automatically makes ing contact with then: by gravity. When a New Field to the Amateur. the amount of chlorine within its capacity the current is closed the loose piece is a point. The disc D is of thin aluminum as required. caused, by the knock of the armature, to be and about 1 inch in diameter. In the cen- A glass tube can be extended through the jarred out of contact; thereby interrupting ter of this punch a hole so that the wire cover into the large glass tube, thus obtain- the current and allowing the armature to R may be pushed through it. A disc of swing back to its original position by force thin fiber or heavy cardboard is glued Jo/>so/u/ioo of the supporting spring. By this time, to the top of the tube. A hole is punched Gloss tube 410b/oct\ however, the loose piece has come in con- in it so that the wire bearing the disc may to b/eochipQ box tact again with the two points, repeating the action as long as electricity is flowing be pushed % inch through it, that is down 1o.tzcp into the tube. One end the No. 34 wiré /om,osi through. the coils. of sePiés yp/re is soldered to the No. 14 wire. This com- oo HOY ac It may be of further interest to know pletes the secondary. Yo/ve that the consecutive blows of the armature The primary is of Empire paper or l'[ :i1,Ì\\\\ _ cause the loose piece to revolve around the heavy cardboard 2% inches wide and 3 supporting points, whereby the contacts are inches in diameter. The primary winding I always bound to be kept smooth and free % P consists of eight turns of No. 14 strand- ÏIII / from any possible impurities. The inventor ed rubber- covered wire, the ends of which P. has submitted the device to extremely are fastened to two battery binding posts It- dew' severe tests, for instance, submerged in f iii i¡ T T. tube % water, buried under ground or exposed The primary is then glued to a small 61 to acid fumes for weeks, while the bells wooden base B. The bottom end of the were continually ringing and are still ei good for long service to -day. This bell secondary wire is soldered to the bottom IIÍ11 % primary post so that the windings are in forthern croch /!s!1 /! //./ is self adjusting, no matter how many cells the same direction. The last thing to do tt it is run on, for the stronger the knock is to glue, not nail or screw, four standard given the cores by the armature, the more will the contacts porcelain insulators on the base. Simple Apparatus for the Electrical Production -which rest upon each The whole should be constructed with- of Chlorine Gas to Be Used in the Laundry. other by gravity- become separated, thus out screw or nails, and if made carefully adjusting the bell automatically for any it will give remarkable results. ing directly a supply of chlorine gas for voltage. This resonator may be worked on any bleaching purposes. This apparatus pro- Again, this bell uses the full magnetic coil up to a 3 -inch size though it is rather vides a ready means of securing chlorine field, because the current is only interrupted too small for a % k.w. transformer. solution or chlorine gas in small quantities after the armature has actually hit the Before winding the tubes both should at little expense. It has a wide field as a be boiled in paraffine. disinfectant or purifier, and is applicable to Contributed by F. K. BILLAU. many and varied industrial uses. (Caution. Chlorine Gas is highly poison- PRODUCING CHLORINE ELECTRI- ous and if taken into the lungs will cause CALLY FOR LAUNDRIES. dangerous congestion. It is advisable to A new field has been recently developed place the apparatus in a well -ventilated to some extent in the application of elec- shaft, carrying the fumes upwardly. -Ed.) tricity to the washing of soiled clothes. This involves a protess making use of chlorine, ELECTRICIANS' NON -CORROSIVE to be used as a substitute for the bleaching SOLDERING PASTE. compounds commonly used for this pur- One lb. vaseline plus 5 fluid oz. saturated pose; and owing to the fact that this has solution of zinc chloride sp. gr. 2.00, plus been largely imported from abroad it has 1% oz. beeswax for a hardener to keep become quite out of reach for ordinary re- compound from running in warm weather. quirements. Melt all and stir well while cooling until An easily made device for the electro- emulsion sets. A little on the joint is all lytic production of is in that is necessary to solder anything chlorine described but A New Electric Bell Having Its Circuit Breake the Electrical World by Mr. H. P. Hill. aluminum. Encased in an Air -Tight Tube to Prevent Cor One of the smaller apparatus suitable for A Speedy Brass Polish-1.65 oz. oxalic rosion of the Contacts. An Extra Rugged Design. home use is described herewith. acid pulverized, plus 153 oz. Tripoli pow- cores. With ordinary bells the armature Referring to the accompanying sketch the der, mix thoroughly. To use, wet a piece really never enters the full magnetic field, various parts of the device for electrolyti- of cloth with water and put a little of the which is, of course, strongest right near the cally producing chlorine are indicated as polishing powder on, then apply to brass. core, for the current is almost immediately follows: As the brass tarnish is reduced, wipe off broken when the armature begins to move In this type the apparatus is automatic with a dry cloth to a bright luster. To toward the cores.

www.americanradiohistory.com 500 THE ELECTRICAL EXPERIMENTER November, 1916

This department will award the following monthly prizes: First Prize, $3.00; Second Prize, $3.00; Third Prize, $1.00. The purpose of this department is to stimulate experimenters towards accomplishing new things with old apparatus or old material and for the most useful, practical and original idea submitted to the Editors of this department, a monthly series of prizes will be awarded. For the best idea submitted a prize of $3.00 is awarded; for the second best idea a $2.00 prize, and for the third beat a prize of $1.00. The article need not be very elaborate, and rough sketches are sufficient. We will make the mechanical drawings. Use only one side of sheet. Make sketches on separate sheets.

FIRST PRIZE, $3.00 SECOND PRIZE, $2.00 THIRD PRIZE, $1.00 A "DESK" RADIO SET. HOME -MADE OVERLOAD CIRCUIT A MOTORCYCLE HEADLIGHT Below is a photo of my radio receiving BREAKER. WRINKLE. outfit mounted in a desk. It is not neces- This circuit- breaker can be made at a Below is a plan for a motorcycle head- sary to explain the different instruments very little cost. Obtain an electro- magnet light generator, which I am using success- which I have mounted in the desk as I to carry the required amount of current fully with a 21-cp. 12 -volt nitrogen Tung- think any one familiar with wireless will and mount it on a base. In front of it sten lamp. recognize them. I rewound a four -bar telephone magneto It is not the instruments as much as the armature with 200 turns of No. 21 D. C. manner of mounting them. A desk makes C. for 12 volts. It could also be wound the set fool and dust proof. liiáüüüübiu with 100 turns of No. 18 wire for 6 volts. I have entered this in your "How-to - I replaced the original shaft with a Make-It" department, as I believe there are longer one, so as to accommodate a gov- perhaps a few who wish to have a receiv- ernor pulley which keeps the voltage steady ing outfit and one that will not require any at all speeds, otherwise the lamp would be extra space. The bottom drawers I use for burned out at high speed. When the Line Current Passing thru the Electro- magazines and books. My connections to Magnet Becomes Excessive, the Spring Strip Is The shaft may be made of a piece of ground and aerial are wired on the rear. Attracted and the Switch Blade Opened. -inch drill rod, and can be drilled in from When I have this desk closed, one would one end with a 4-inch drill to accommo- mount a piece of spring steel as shown in date an insulated contact pin as in the or- sketch A. If an overload of current be iginal shaft shown in the diagram at "A." sent through the magnet it will attract the The bearings may be made of brass or steel spring and release the switch blade, with a little skill may be made ball bearing thus opening the circuit. The same thing by using small cups and cones. I used will happen on a short- circuit. An external cups taken from a couple of old motor- resistance may be necessary to adjust the cycle pedals and made them a tight fit in circuit -breaker to open at the right time. brass plates. Iron. or steel will not do as Contributed by H. BOCK. they carry magnetism. For cones, I used cury through chamois or cloth. This solder will stand more heat than any other and only a small amount should be used. Before using, wet the pieces to be soldered with a solution of zinc chloride, and apply solder with the finger. Contributed by H. V. QUINLAN.

ANNUNCIATOR HINTS. A cord, fastened to the reset handle of an annunciator, can be used where the instrument is too high to read. The illustration shows how this is done. A nail between two knots in the doubled string An Automatic Governor Pulley to Prevent Execs protects the handle against too severe a pull. Voltage on Motorcycle Dynamo Lamp. The second arrangement is adapted to an bicycle cones which I annealed so as to drill out a sliding fit on the shaft. The governor pulley is made up of a brass disc a, with a hub made of a brass 8 nut soldered in the center on one side, and In This Exceedingly Compact Radio Laboratory pinned to the end of the shaftwith a cotter There Is Combined Neatness as Well as Freedom pin as shown at "B." from Dust and Meddlesome Fingers. 6 Next comes a 1/16 -inch fiber disc b, the pulley 1/16 I have receiving out- c, another -inch fiber disc b', a hardly suppose that a flat disc d, fit installed therein. When I open it stran- brass about 1/16 inch, a 4-inch gers are always quite surprised to see how fiber or brass disc e, beveled about 45 de- neatly the instruments are arranged. grees on one side next to the pulley and a Contributed by JOHN F. CARLSON. 6 small shafting collar f, made of a brass 0 connector such as used for connecting electrical wires. A COLD SOLDER. Finally you need a tightly coiled spring Dissolve sulphate of copper in water until about 3 inches long x 3s -inch diameter the water will dissolve no more. To this which goes on the beveled disc next to the solution add bits of scrap zinc until all the pulley. This serves to force discs and copper Sulphate goes down in a brown pow- pulley together like a clutch, which.it really der; wash two or three times by adding is. On the tightness of the spring depends water, let it settle then pour off the water the generator speed. When the governor and dry the powder. When dry, place in reaches the speed for which it is set, the vessel an. earthenware and add one -fourth Clever Schemes for Rigging up a Chain Pull to pressure of the spring tends to expand it, as much mercury as powder. Add enough Reset the "Drops" on Any Annunciator. thereby causing the clutch to slip and in sulphuric acid to just make it into a thick this way keeping the dynamo speed just paste, and then wash out the acid with hot nunciators having a push rod to control right. water. If the paste is too hard add mercury the drops. Contributed by and if too soft, strain out the excess mer- Contributed by R. M. MARTIN. ARTHUR W. HUBERTY.

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 501

HOW TO MAKE A REVERSING ANOTHER HOME -MADE BLOW ball is driven on the other end to prevent SWITCH. TORCH. ' leakage. Most experimenters have need at times Secure a tin can with an opening at the Contributed by WALTER D. SILOLL. of a reversing switch, but the cost is usually top 1 inch in diameter. Take an old socket prohibitive for a good one. The switch out- of regular size and remove the threadeu RELAY CONTROLLED FIRE OR tube. Fit it in the opening, half way in, BURGLAR ALARM e and solder it in firmly. Next get a blown When the fire alarm is rung by pressing brass plug fuse, break the mica and pass the push or switching device, as at A, the :Iti cío armature of the relay will be attracted clos- I through a Y8-inch brass tube and solder I-r them together. Then pass a heavy wick 1.1 through this tube. Obtain a narrow metal fig /a f/g 2,4 tube, bend to the shape shown in illustration, solder it to the can and part of the 1. socket, attaching to the other end a narrow rubber tubing. Fill the can with alcohol and screw its cover on tight. fig./ fiad IIIIIIIIIIIIII A N J.-1 o : fo.se,o/vg ifelo/JUbe Clever Alarm Circuit in which Contact or Push A Closes Relay, Ringing Bell; Push C Opens Cir- _Soofétsüe//. cuits. ing the contact at B, causing the alarm to Details of Make -Up of Reversing or 4 -Way Switch. Useful in Controlling Lamps or Motors. ring. At the same time it maintains a So/de/ closed circuit through the relay as well as lined herewith is comparatively simple, easy the bell, with the result that the armature to make, and works on the rotary principle Rubber /ube holds the contact closed, and the bell rings featured in all the newer instruments. l continually. The base, Fig. 1, is made of hard rubber Another push button C can be suitably or thoroughly seasoned wood, ''4 inch in placed and so connected that when pushed thickness and about 3 inches square. After it will short -circuit the relay and allow the the base is shaped, draw diagonal lines from /Mich armature to open the circuit. This is quite the opposite corners. On each line 14 an advantage over the mechanical reset inches from their intersection drill a 3/16 - when the relay must be placed so that it inch hole. Another 3/16 -inch hole is drilled i can be reached by the average man. at the intersection. Now cut four pieces of Efficient Style of Electricians' Blow Torch Made Contributed by N. M. FERRIS. sheet copper or brass as shown in Fig. 1 -A. from Odd Parts. By means of binding posts inserted in the FOR THE AMATEUR CHEMIST. corner boles in the base and the holes in Get a 3 -inch brass plug to cover the brass The following is a method for preparing these strips, the strips which serve for con- tube, in order to prevent the alcohol from a substance that will detect an acid. In a tacts are secured to the base. They should evaporating. pot put the outside leaves of cabbage. Cov- lie diagonally across the base with the long Contributed by D. JIMENEZ. er them with water and boil for ten minu- The ends toward the center. ELECTROSCOPE FROM ORDINARY tes. water will have acquired a yel- The construction of the switch -blades is low tint. To test for an acid put some of TUMBLER. this liquid in a test Pour few the next step. On a piece of sheet copper For making experiments tube. a drops (or brass) lay off two concentric circles in static elec- of the suspected substance in and shake the and two inches in diameter. The blades tube. may then be cut out and shaped as indi- If the yellow color is destroyed the sub- cated at Fig. 2. The ends of the blades, stance is an acid. To make the change also the edges of the contacts, Fig. 1 -A, more clear, some lime water can be added should be beveled so as to work smoothly. to the cabbage solution. This will inten- The cross -arm to support the two blades sify the color of it. should be of hard rubber 1 inch x The lime water for the above experi- x % inch drilled as shown in Fig. 2 -A. ment can be made very easily in the fol- Attach as shown in Fig. 3. M M are the lowing way: Fill a bottle with water. Put blades, D the cross -arm and E E machine in a few pieces of calcium carbide. After screws. Now insert a 3/16 -inch machine the carbide is slaked, filter the water screw through the base, screw a. hexagon through a piece of filter paper. This will nut on it, place the cross-arm over this and be lime water. screw another hexagon nut over it. The Contributed by GEORGE E. MINCH. spring S makes far smoother action. Then attach a hard rubber knob for operating SWITCH FOR OPEN AND CLOSED the switch and you are ready for business. CIRCUIT BATTERIES. Connections for this switch in a permanent The following is a description of a magnet motor circuit are shown at Fig. 4. switch that has two uses: first it enables Fig. 5 shows how this useful switch can the experimenter to have at his disposal be used with two, 2 -point switches, so that two different sets of cells such as storage or dry cells on one side and Daniel or Gor- don cells on the other. As the diagram is self -explanatory, a further explanation is to binding posts 0

A Cheap Electroscope Constructed from a Glass Tumbler, Wire and Tinfoil. tricity, electroscopes are often used. How- ever, these are too expensive to buy for just a few experiments and thus the ex- [11t 1 111 periments are very often never made. Fig. Qoeocitcuitce//s C/osedéiituifce//s. ' 1, shows the construction of a simple and cheap electroscope which may be made in Switching Scheme for Using Either Closed or a few minutes' time. The jar may be a Open Circuit Batteries. Wiring Hook -Ups for Using 4 -Way Rotary Switch. drinking glass or jelly tumbler. The top is unnecessary, except to state that the greater a piece of tight-fitting, paraffined wood with the number of points on the switch, the a lamp may be turned on or off from any a piece of coarse wire driven through the greater the amount of current that can be one of threepoints. center of it. The lower end of the wire is varied. Contributed by bent in the form of a hook over which a Contributed by AN EXPERIMENTER. piece of very thin tinfoil is placed. A lead EDW. C. CONNELLY.

www.americanradiohistory.com 502 THE ELECTRICAL EXPERIMENTER November, 1916 Experimental Chemistry By Albert W. Wilsdon Sixth Lesson OXYGEN. Fig. 27. [Note: For method of bending heated air, .and should be rejected]. After [Experimental] glass tubing, see June, 1916, issue of THE you have allowed this heated air to bubble the previous issue we went over the ELECTRICAL EXPERIMENTER, under "Bending through the water, place the delivery tube occurrence, modes of preparation, and Glass Tubing. "] Next set up the appara- under the bottle, and observe and record properties of this gas. It is advisable tus as shown in Fig. 26, by pushing the any change which takes place, both in the that the reader go over all these de- delivery tube through a one -hole rubber test tube and the receiving bottle. When tails before taking up the experimental stopper which just fits a test tube. [Al- you have filled one bottle [the indication part, so that the operator may become fa- ways remember when inserting glass tubing of which appears by the gas escaping around into a hole in a rubber stopper, to wet both the sides of the bottle] REMOVE the flame StOnd fE the tube and the hole well, and push the from the test tube, and take the delivery tube in by twisting. Never try to insert a tube FROM THE WATER, being careful OM; hole stoppers l glass tube in a stopper without wetting not to upset the bottle of collected Oxygen. Oe/rvery tuée Test tube both tube and stopper.] mo Fill 4 eight- ounce, wide-mouth bottles full of water, as shown in Fig. 29, and ßefe%Y//Jl bOtl/e slide a glass plate [4x4 inches] evenly over f HC/O. á the mouth of the bottle, so that no air MnO: i bubbles remain in the bottle, and when the glass plate is in this position, invert the bot- i tle, grasping it as shown in Fig. 28, and fiy.26 place mouth down in the tray containing the water. When the bottle -full of water is UNDER the water in the tray, remove the froy glass plate. This will leave the bottle in an upright position, filled with water. Be sure that there are NO air bubbles in the bottle, and if any appear, repeat the operation, till -fill // Photograph of Apparatus Shown in Fig. 26 Set all have disappeared. Up in the Author's Laboratory. Mix on separate papers, about 8 grams of Fig. 26. Arrangement of Apparatus to Produce Potassium 5 [Note Oxygen by the Decomposition of Potassium Chlorate [KCIO,] and grams :- If the delivery tube is allowed to Chlorate. of powdered Manganese Dioxide [also remain under the water after the gas has called Manganese Peroxide], [MnO,]. Mix stopped generating (which is caused by re- miliar with the conditions surrounding the the two together by stirring thoroughly with moving the heat) the water will climb into preparation of Oxygen. a wooden splint or pencil. [It will not be the tube, due to a vacuum action, and if As stated in the last installment, the gas out of place to mention here that Mangan- the cold water comes in contact with the is usually made in the labora- hot test tube, it might crack tory by the decomposition of it. This can be avoided by Potassium Chlorate [KCIO,], always remembering that by the displacement of water. when the heat is taken from Oxygen may be prepared the test tube ALWAYS RE- by the electrolysis of water MOVE the delivery tube with the apparatus described OUT of the water.] in the October issue; it is pre- Place another bottle [filled pared with the apparatus men- with water in the same man- tioned by filling the glass ner as before], and place chamber with water, to which over the opening of the de- a little Sulphuric Acid livery tube. Prepare four [H,SO,] has been added, to [4] bottles of Oxygen. better conduct the electricity. When you are ready to The Oxygen is collected at the perform the following tests, anode [or positive electrode] slip one of the glass plates and Hydrogen is liberated' over the mouth of the bottle, from the cathode [or nega- in which the Oxygen has tive electrode]. Fig. No. 21 been collected. [Always per- there given, shows how the form this operation while the Fig 30 Show'ng Glass Cover Slightly Displaced Wh' e Experiment ng F'g. 3 apparatus is set up and needs Buruing Magnes uni Ribbon in Oxygen. Fig. 32. Beautiful Effect Produced bottle is under water, other- no further description. Refer by Burning Iron Wire in Oxygen. wise the Oxygen collected to Methods of Preparation, will escape and air will be Method No. 3. ese Dioxide [MnO,] is sometimes adulter- admitted.] Set the bottle right -side uo EXPERIMENT No. 6 ated with other substances, which, when [or with the mouth of the bottle up, still rill a large tray [about 10x12x4 inches], heated with Potassium Chlorate, may give being covered with the glass plate]. rise to explosions. It is, therefore, advis-

I IeI Jl41Jl l I 1111111111 I I I I able to test this compound before using, by mixing a little with some Potassium Chlor- I n II , - --- ate [KCIO,], and heating in a test tube. If the decomposition takes place quietly, without explosions it may be used for the preparation of Oxygen. [If any slight explosions occur, reject the compound and obtain pure MnO,. NEVER use this compound, if, after or during the tests, slight explosions occur; to do so, might result in injury.] both substances are thoroughly mixed in the proportions stated above, pour the mixture into the test tube, spreading it in the manner shown in Fig. 26; connect the apparatus as shown also by Fig. 26. After you have connected the apparatus, place the lower end of the tube under the bottle of lID1 11 I11I. ,, lllllllllll water. [Do not lift the bottle from the Shape of Glass Delivery Tube and How Water Level Rises Above Top of Bottle. The Bott e Wh'ch s to Trap the Oxygen F'g 26, water, but place the delivery tube under the is Filled with Water and a Plate of Glass Placed bottle WHILE UNDER WATER.] This [Note: -It is not necessary to remove Tightly Over it Before Inverting. should be done after the first portions of each bottle from the water as it is filled; or a large pan with water to about 3 inches the gas have passed from tip tube [which it can be left under water if a weight is deep. Bend a delivery tube as shown by are indicated by bubbles, and which is only (Continued on page 524)

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 503

and wipe off as dry as convenient; then lay -which, it will be remembered, are in the them between uncolored paper, or between form of flakes -to present opposite ends to newsperpers, and press by laying books or the middle of the bobbin alternately under - some other flat substance upon them until the influence of the alternating current. The .R6,k`. 1 ..i: the surplus oil is absorbed, when it is ready lateral movement is attributed to the mu- for use. tual attraction and repulsion between neigh- le. Directions. -For taking off patterns of boring particles. embroidery place a piece of thin paper over To make the oxide in the form required _, the embroidery to prevent soiling; then lay for the experiment, cut a piece of tinned !a._ on the magic paper, and put on the cloth iron from a can and leave it in an open ` you wish to take the copy on, to embroider; fire until the surface is covered with black pin fast, and rub over with a spoon handle; oxide. If carefully removed and allowed tò mula and every part of the raised figure will show cool, a little gentle bending between the upon the plain cloth. To take impressions fingers will detach the oxide in the form of leaves on paper, place the leaf between of irregular flakes. two sheets of this paper, and rub over it The next experiment is even less exacting EDITED BY 5.6ERNSBACK liard, then take the leaf out and place it in the matter of apparatus, only a little fine- Under this heading we publish every month use- between two sheets rub ly powdered graphite or bronze powder be- ful information in Mechanics, Electricity and of white paper; Chemistry. We shall be pleased. of course, to again, and you will have a beautiful im- ing required. The current, which may be have our readers send us any recipes, formulas, pression of both sides of the leaf or flower. drawn from the house supply, should be wrinkles, new ideas etc., useful to the experi- about 200 volts D.C. Two wires should be menter, which will be duly paid for, upon publication, if acceptable. DEVICE FOR SHAPING NEW carried from the lighting circuit, provided BRUSHES FOR COMMUTATORS with insulating handles for convenience, The drawing shows a simple device for and having a high- resistance voltmeter in EXPERIMENTER'S APHORISMS shaping new brushes for commutators of series. Place a small heap of perfectly dry In the following, we wish to give to the motors and dynamos. The strip A is printers' bronze powder on a sheet of pa- Experimenter some hints as to the use of the fastened different ingredients and how to work them: to the board B, while piece C is per, and insert the ends of the wires in (I) Always bear in mind that exact working hinged to B. D is a wing nut and screw, opposite sides of the heap. The voltmeter a requires ACCURACY, of formula CLEANLI- which can be clamped to keep the piece C will not at first register the passage of a NESS, PATIENCE, and SKILL. at its (2) Know what you are about, before you start adjusted angle. current; but upon gradually bringing the to experiment. The old brush is laid on as shown at E, wires closer together the needle is ultimate- (3) THE HISTORY OF FAILURES IS THE and C adjusted to the nearest angle. The HISTORY OF SUCCESS" goes an old adage, and ly deflected. After this they may again It applies well to the experimenter. file is placed on B. The new brush is be separated without stopping the flow of (4) Many times impure, wrong or deteriorated held against B bearing against the file. current. Moreover, if the wires arc raw spell instead materials, FAILURE of SUC- This device roughs out the brush to ap- brought fairly close together they may be CESS. proximately (5) A great many of the chemicals and in- the right shape. The clamp slowly separated, not only from each other, gredients required, cannot be obtained from strip A may be graduated to correspond but from the powder, without interrupting drug stores; buy them at a reputable supply with different angles. house. the flow of current. Upon inspection it (6) BEFORE CONDEMNING A FORMULA, be After beveling off the brushes in this will be found that the wires are connected sure the fault does not lie with the manner of way to approximately the correct angle, either with each other, or with the pow- handling It, or the purity of the ingredients. they are placed in the brush holders and (7) Be sure to mix the materials comprising der, by an exceedingly fine thread of a certain formula in the proper sequence. shaped to fit the commutator curve accu- bronze. With care it is possible to obtain (8) When starting to prepare a mixture, rately by pulling a piece of sand -paper back a separation of an inch or so. No doubt especially one containing liquids, ask Yourself: "IS THE SPECIFIC GRAVITY CORRECT, AS the chain is produced by a welding to- INDICATED BY A HYDROMETER? IS THE gether of the minute particles composing TEMPERATURE RIGHT? IS THE QUANTITY it under the influence of heat, generated OR WEIGHT RIGHT? (9) Acids and water, when mixed, should be by the current. If graphite powder is used, proPOURED several threads can be drawn simultane- ACIDpuSHOULDthB erINTO THE ously. WATER, and not vice versa, as the solution is liable to be forcibly ejected from the containing The third experiment to be described vessel and into the mixer's face. is of a very simple character, and only any SYSTEMATIC requires a carbon filament lamp and a a ( floatingating THERMOMETER adHYROM-D R ETER, as well as measuring glasses and perfectly dry, warm cloth. Immediately scales, should always be provided, as GUESS- A Time -saving Carbon Brush Facing Device after switching off the current, that is WORK is EXPENSIVE, and SOMETIMES lamp is should re- FATAL. and forth under the brush. Hold down while the still hot, it be and rubbed cloth. (11) Put labels on ALL bottles, boxes and on both ends of the sand -paper -not up. moved briskly with the packages with FULL INSCRIPTION as to their The becomes charged by by C. ANDERSON. outer surface Contents, it will avoid troubles and mistakes. Contributed by induc- (12) Remember that a beginner cannot expect friction and the inner surface to make articles AT FIRST, whiçh will com- EXPERIMENTS OFF THE BEATEN tion, sometimes sufficiently to attract the pare with regular manufactured products. S.G TRACK. filament to the side and hold it there. At FORMULA FOR DISINFECTANT. The following experiments are not only the same time a luminous glow is observed interesting, but have the additional charm in a dark room. 1 oz. 6 drains Guaiacol of novelty, being a kind that one does Contributed by H. J. GRAY. 1 oz. 3 " Eucalyptol of 6 " Menthol not usually come across in the text -books. For the first there will be required a WOOD POLISHES. 1 oz. Carbolic Acid It bobbin about four inches in length with a A polish for burnished wood surfaces 3 Thymol may be made of the following: Wood " Oil Clove central hole an inch or more in diameter and having a few hundred double Pulp, 40 parts; Hydrochloric Acid, 44 Enough Alcohol to snake 2 turns of lbs. covered wound it. This parts; Chloride of Lime, 151 parts; Tur- To be sprayed about with water. cotton wire on should be fastened end -up on a sheet of pentine, / part. Mix in the form of a TO PRINT A PICTURE FROM THE mirror glass and the ends of the wire con- paste and smear over the surface, allowing PRINT ITSELF. nected with a source of rapidly alternating it to remain a short time and remove it by -The Page or picture is soaked in a solu- current. quick strokes of a soft brush or leather, tion, first of caustic potash and then of tar- Into the hollow core drop a few flakes thoroughly cleaning the surface. Rub taric acid. This produces a perfect diffu- of black magnetic oxide of iron, prepared gently to a polish with a fresh piece of sion of crystals of bitartarate of potassa as described below. At first no effect will cloth or chamois. through the texture of the unprintcd part be observed ; but let a soft iron bar, or For very highly polished surfaces the of the paper. As this salt resists oil, the ink what is better, a bundle of soft iron wire, following may be used Dissolve 5 parts roller may now be passed over the'surface be inserted for a moment and withdraw; Potassium Carbonate in 300 parrs Water; without transferring any part of its con- the particles of oxide will at once become dissolve in this 500 parts shaved -up Bees- tents except to the printed part. endowed with extraordinary activity. The wax by 'boiling until the wax is partially flakes that were formerly at rest will be saponified, replacing the water evaporated. Magic Paper. -Take lard oil, or sweet seen to be dancing vigorously under the Remove from the fire and stir until cold; oil, mixed to the consistence of cream, with influence of the alternating current, the add Oil of Turpentine, 800 parts, stir con- either of tke following paints, the color of movement being both side to side and up stantly until a smooth emulsion results, which is desired: Prussian blue, lampblack, and down. The probable explanation is then add 800 parts of Distilled Water, con- Venetian red, or chrome green, either of that the particles of oxide become perma- tinuing the stirring. Wash, rinse and dry which should be rubbed with a knife on a nently magnetized during the brief time the surface to be polished. Apply the plate or stone until smooth. Use rather that the iron core is within the bobbin. The paste as uniformly and as thinly as pos- thin but firm paper; put on with a sponge, polarity thus induced causes the particles sible; rub off with a soft woolen cloth.

www.americanradiohistory.com 504 THE ELECTRICAL EXPERIMENTER November, 1916 OR Fóß `ITS GREAT FUN

----y._--,-sl.;, Become Bo s, Greater Fun Valuable Pri: "Gilbert S... Enrollment in the Insti of The First Degree - (2) Send me a photograph or drawing of al KNOW what you boy- friends "Erector Engineer" ceptable Brik -tor model. mine like! That's why I've thought The Second Degree- (3) Send me a photograph showing that out this new and big idea that will "Erector Expert Engineer" know how to put together a motor more fun than you ever The Third Degree parts of which are included in the Er give you - Master Engineer" Electrical Set. dreamed of before with your Erector, "Erector Get busy right now: Do one of the a Brik -tor and Erector Electrical Sets. The Valuable Awards Given To Boys things immediately, and I will make you a r What is the "Gilbert Institute of Who Win the Third Degree ber of the "Gilbert Institute of Erector 1 Erector Engineering ?" neerin , ' send you the handsome "Erector (1) A handsome diploma ready for framing, con- gineer' 'Diploma, and a Certificate telling You must write for my free, hand- ferring upon you the Degree and Title of some book which contains the whole "Erector Master Engineer. story. However, the fol- (2) A beautiful, gold "E. M. E." Fraternity Pin interesting which you can wear on your coat so that lowing will give you an idea as to what everyone will know of your ability. FOR LIVE WIRE a big thing it is: (3) A salaried position with The A. C. Gilbert know the great yearly prize con- Co., during the holiday season, following You your winning the "Third Degree." This tests that I have held- giving away position is with our Demonstration Corps, Automobiles, Motor -cycles, Canoes and and will pay you a salary of $10.00 per week hundreds of other valuable gifts for the for three weeks with an extra commission of best models built by boys. 1% on total sales. (4) A recommendation, signed by Mr. A. C. Now -I am going to continue to give Gilbert, for a position with any firm, in- these prizes, and in addition -all boys dicating that you are the type of boy who who send me photographs or drawings is sure to make good, and who has won "The Toy Lik4 highest standing in the "Gilbert Institute of of acceptable models of any Gilbert Erector Engineering." Hello, Boys! Do you own a set of Ere, Toys, will be given free enrollment in If you don't, you have no idea what a 1 the "Gilbert Institute of Erector En- i fun you are missing. gineering." Erector is the toy for the "live - wire" boy -the boy who has im- Just think what this means to you! agination and ability. With a set You will become a mem- of Erector, he can build models of the world -famous engineering feats ber of the Greatest Toy - like the Brooklyn Bridge, the Pan- ,,, Engineering ama Canal, the great skyscra- university of pers of New York City, the iA the world. Eiffel Tower, and hundreds ; such of other things as Ma- - You will have Aeroplanes, an opportun- It will, of course, be necessary for you chinery, Automobiles, to secure the First Degree Diploma of Battleships, Engines, Printing Press- ity to win es, Steam Shovels, Farm Implements, "Erector Engineer" before trying for the etc., etc. rYr-7 prizes, and the Second honors, de- Second Degree Diploma, Degree Diploma before trying for the Big Exclusive Erector Advantage' grees a n d steel toy Third and Highest Degree Diploma. 1 -The only actual structural diplomas that you will be proud of all the First Degree by 2 -The only construction toy with inter loads of You can secure locking edged for building squar your life. And you will have of the following three girders fun while you are doing it. doing any one columns. things: 3-Most parts for building largest an. of Listen! The "Gilbert Institute (1) Send me a photograph or drawing of an ac- strongest models. Erector Engineering" will confer on ceptable Erector model with or without 4-Big, reinforced steel wheels, grove boys Three Degrees as follows: motor attachment. and hubbed forevery engineering purpose

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www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER ir Engineerin tOYS WAL ENGINEERING :'::..:.-t ''l,\'

>,r Engineers! 'r....% 'er Before! Not Only Nie Best Models, but Free Erector Engineering." to do in order to secure the next highest Valuable Prizes to Boys Who Great Fun Learning Elec- e-"Erector Expert Engineer." the complete story of the "Gilbert Insti- Build the Best Models tricity Secrets 1 Erec or Engineering'! The First Prizes are a handsome Saxon auto- Learn to do electrical experiments and stunts out the coupon which appears at lower mobile, shown below, and a beautiful Shetland that will make your friends' eyes open with land corner of this page; mail it back to Pony. Other prizes are Motorcycles, Bicycles, wonder at your electrical knowledge and ability. id will send you I your free copy of my Canoes, Camping Outfits and hundreds of other Show them that at your bidding the wonderful book which tells all about as well as it, valuable gifts. ful f e luable rewards. power o electric-ec Go after these f! itÿ will do marvelous President. prizes. boys! Gard- things for you -and The A. C. Gilbert Co., New Haven, Conn. ner Grote -a St. that you are acquir- Louis boy -won the ing knowledge that first prize of the may make you an- automobile last other Franklin, Mar- year and the Mayor coni or Edison in the S-GILBERT'S of St. Louis presented it to him. %. Will you bring this honor to your city and yourself this year? Send photograph or drawing of your model along with properly filled out entry blank. One of these entry blanks is included in each copy of my great magazine for boys - OR years to come. Get "ERECTOR TIPS" Erector Electrical Set and "Erector Tips" is full of articles Gilbert's =ictural Steel" that real boys like. Tells about Elementary Course in Electricity great achievements, how -_urdy electric motor that 200 athletic Once you see it, your hands will fairly twitch to will lift to do magic tricks, etc. no when properly get hold of it. You will be able to build your geared, comes free and with most sets. Contains gripping thrill- own motor that will operate both backward and ing stories, that delight all 6 -Three big illustrated Man- forward, and regulate its speed at will, so that uals showing red -blooded boys. your Erector models, mechanical toys, electric over 500 models. Also keeps you informed about the Of course you can build thou- "Gilbert Institute of Erector Engineer- trains, etc., can be operated perfectly. sands of others as you acquire in the Diplomas and awards. And the great, big, beautifully illustrated Send loe for a year's subscription today. proficiency. book, which comes with every set, will show 7 -Free membership in the Here Is the New and Wonderful Toy, you how to do more than a hundred intensely "Gilbert Institute of Erector in eresting electrical experiments-how to build Engineering" with handsome Boys! GILBERT'S your motor, make magnets, wire door bells, and diplomas and other awards, "The Toy That electric lights, construct switches, etc. including the $5000 Prize Con- 12410: Completes Con- Be sure to get this great Set, boys! There's test for Boys. /WO- Ira. or struction Toys" no limit to its fun. Price $5.00 (Canada $7.50). The Famous "FOUR" Just think what Brlk -tor means to Mail back the coupon today for my Free Book Contains every essential engineer- every boy who now owns a construc- ing tion toy set. part for building thousands of It will enable you to complete the models. Has big girders, large and framework models that you build I THE A. C. GILBERT CO., small wheels, shafting, corner plates. with Erector or any other construc- angle irons. pinions, pulleys, ears. tion toy - and to make finished 160 Fox St., New Haven, Conn. nuts and bolts and the great electric houses. churches, factories, bridges, motor. tunnels, brick piers, tile walks, and I Send me your free book which tells the story of Also included is our beauti- various other models with steel bricks fully illustrated Manual No.7 show- In brilliant color combinations. the "Gilbert Institute of Erector Engineering." ing how to build all kinds of models. Just thinkof the fun! The price of cked in a handsome, hardwood cabinet. Brlk -tor Is $5.00, complete. with a I Name 11 for only $5.00, Price in Canada big Instruction Book, beautifully il- -37.50. lustrated. Canada-57.50. Dealers Dealers everywhere sell Erik -tor. Street everywhere are glad to show you Co In and see it or send to me for be new Erector Sets -$1.00 to $25.00. descriptive booklet. I City State

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www.americanradiohistory.com 1Noccrnber, 1916 THE ELECTRICAL THE ELECTRICAL EXPERIMENTER 1956 Novrmlx'r, EXPERIMENTER

A ry' á p,7474/ dès A -- Engineering oYs

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Become r Engineers! / Greater Fun Before! Not Only Ir but Free Valuable P j Best Models, Enrollment in the " Gilbert Insti Erector Engineering." (2) Send me a photograph the next highest you boy- of The First Degree- or draainr '- miler to secure Valuable Prizes to Boys Who Great Fun Learning Elec- IKNOW what friends "Erector Engineer'.gin eer ceptable Briktor model. :or Expert Engineer." mine like! That's why I've thought The Second Degree - (3) Send me a photograph showing e'ele story of the "Gilbert Insli- Build the Best Models tricity Secrets Expert Engineer" know how to out this new and big idea that will "Erector put together a r r Engineering"! The First Prizes are a handsome Saxon auto- Learn to do electrical experiments and stunts parts of lower more fun than you ever The Third Degree- which arc included in d coupon winch appears at mobile. shown below, and a beautiful Shetland that will make your friends' eyes open with give you "Erector Master Engineer" Electrical Set. roi this page; matl it back to Pony Other prizes are Motorcycles, Bicycles, wonder at your electrical knowledge and ability - dreamed of before with your Erector, I send you your free copy of my Canoes, Get busy right now: Do one of Camping Outfits and hundreds of other Show them that at your bidding the wonder- which tells all about it, as well as Brik-tor and Erector Electrical Sets. The Valuable Awards Given To Boys things immediately, and I will make valuable gifts. ful power of electric - arils. Co after these tl NVhat is the "Gilbert Institute of Who Win the Third Degree ber of the "Gilbert Institute of Lo ity will do marvelous neering. send you the handsome E. President. prizes, boys! Card- things for you -and Erector Engineering ?" ner Grote -a St. ready for framing, con- , you are acquir- (I) A handsome diploma gincer' Diploma, and a Certificate ls, A Glhen Co New Haven, Conn. that c. write for my free, hand- the Degree and Title of Louis boy--won the r. ing knowledge that You must ferring upon you Engineer." first prize of the -- - I ' may make you an- some book which contains the whole "Erector Master 1 automobile last story. However, the fol- (2) A beautiful, gold "E. AI. E." Fraternity Pin other Franklin, Mar- interesting which you can wear on your coat so that year and the Mayor coni or Edison in the lowing will give you an idea as to what everyone will know of your ability. FOR LIVE WIRE S-GILBERT'S of St. Louis pre- a big thing it is:- (3) A salaried position with The A. C. Gilbert sented it to him. You know the great yearly prize con- Co., during the holiday season, following \ \'ill you bring this your winning the "Third Degree." This honor to your city and yourself this year? tests that I have held -giving away position is with our Demonstration Corps, Send photograph or drawing of your model Automobiles, Motor -cycles. Canoes and and will pay you a salary of $10.00 per week along with properly filled out entry blank. One hundreds of other valuable gifts for the for three weeks with an extra commission of of these entry blanks is included in each copy of best models built by boys. 1,7, on total sales. E my great magazine for boys - (4) A recommendation, signed by Mr. A. C. OR years to come. Get Now -I am going to continue to give Gilbert, for a position with any firm, in- "ERECTOR TIPS" these prizes, and in addition -all boys dicating that you are the typepe of boy who Gilbert's Erector Electrical Set and who send me photographs or drawings is sure to make good, and who has won "The Toy Like crural Steel', "Erector Tips" is full of articles Elementary Course in Electricity models highest standing in the "Gilbert Institute of that real boys like. Tells about of acceptable of any Gilbert Erector Engineering." great athletic achievements, how Once you see it, your hands will fairly twitch to Toys, will free Hello. Boys! Do inn own asetof -'y nk

Yo. br.rßl by mrnGonins "The Elecnical ae,ra 71i1ú,0 to adrrrd.ers. Experimente/' tarn wrilmg to adanlMere. rots beuehl by mentioning "The Elrcbrcal Esrc.,n,rnrr. www.americanradiohistory.com 506 THE ELECTRICAL EXPERIMENTER November, 1916

Our Amateur Radio Station Contest is open -to all readers, whether subscribers or not. The photos are judged for best arrangement and efficiency of the apparatus. To increase the interest of this department we make it a rule not to publish photos of stations unaccompanied by that of the owner. Dark photos preferred to light toned ones. We pay each month $3.00 prize for the best photo. Make your description brief. Address the Editor.

AMATEUR RADIO STATION $10,000 CASH PRIZE -IF YOU ARE A KARL DUERK'S RADIO STATION. CONTEST. "WHALEBONE" EXPERT. As I am always interested in pictures of Monthly Prize, $3.00. Ten thousand dollars cash will be paid to radio sets I take this occasion to send a This month's Mice winner. anyone for the discovery and assignment of picture and description of my set. It is of all rights in any new practical process for my own design and construction and the EXPERIMENTAL LABORATORY the commercial, profitable and general utili- results have quite exceeded my expectations. OF LIVINGSTON WELCH. zation of whalebone, announces Mr. Aaron My receiving set is of the cabinet type An excellent experimental electrical and Sapiro of First National Bank Build- and contains a loose coupler, two galena radio laboratory is owned by Mr. \ Velch. ing, -San Francisco, Cal. It has heretofore and a silicon detector, a large single layer He is seen sitting among his various elec- been used principally in the manufacture loading coil, a fixed condenser and a vari- of corsets and whips. able fixed condenser and Murdock special Such a process, if of- phones. fered, must be satisfac- My transmitter is composed of a helix, tory, in their exclusive an adjustable high tension condenser, spark discretion and in all gap, 1%" coil and the transmitting key. commercial and scien- I use an aerial 75 feet long and 42 feet tific respects, to the high, composed of four copper -clad wires parties authorizing this offer. The offer ex- pires January 1, 1917. The receiving set consists of a large, double -slide tuner, a loading coil with a very high inductance, a rotary variable condenser of the Gernsback type, and two detectors, a crystaline and a Radio - son. The stopping condenser has three different capacities and is manipulated by means Karl Duerk Busy at His Radio Instruments. of a rubber knob switch. A small switch permits and a lead in of No. 6 copper wire run to the operators to change the lightning switch. from the crystal de- With this receiving set NAA can be tector to the Radioson. heard with the receivers off -also 8 NS, 8 The 'phones are also AEV and about a dozen amateur and E. I. Co., make and several commercial stations. The Excellent Electrical and Radio Laboratory of Livingston Welch. are wound to 2,000 KARL DUERK. ohms. Defiance, Ohio. trical apparatus and we'll bet dollars to For sending, one of their one -inch spark doughnuts that there are 90 per cent of coils is utilized with two three -volt bat- GIRL ASCENDS 426 -FOOT RADIO our young readers who would like to teries and constant communication with MAST. change places with him. Mr. Welch writes ships in the harbor is carried on. The set is extremely compact and hand- Certain repairs had to be made to the top us as follows in reference to his radio ac- of the Marconi tivities: some, and with the aid of a four -wire aerial of one of the steel towers seventy -lice feet long, Key West, Colon, Ar- wireless station near New Brunswick, N.J., In my radio transmitter I use a one -inch workman was assigned to a I ngton and other stations are readily heard. recently, and a spark coil, 2 high tension condensers, the summit, 426 feet above the and a wave me- Readers of THE ELECTRICAL EXPERIMENT- go to spark gap, % K.W. helix ground, in a swing operated by ropes and ter. I have been heard at a distance of 15 Brandes' receiv- pulleys. miles. I have two pairs of I'm going up with him!" announced ers, one 2,000 ohms and the other 3,200 of the man- a silicon de- Miss Nellie Albee, daughter ohms. I use a loose coupler, ager, M. B. Albee. tector, loading coil, together with a varia- Her father protested, but Miss Albee said ble and a fixed condenser. "You took mother up 395 feet Monday af- The aerial is 40 feet high at one end and and I'm going to beat her record." It is composed ternoon, 30 feet high at the other. So the girl took her place in the little of two strands of copper wire, each 150 bos'n's chair alongside the mechanic and feet long. With this set I have obtained the tower, NAA, was hoisted to the very top of very good results, having heard she sat while he did his work. WSL, \VUL, etc. where LIVINGSTON WELCH. Port Washington, L.I., N.Y. JOHN HAYS HAMMOND TESTING WIRELESS TORPEDO AMATEUR RADIO SUCCESSFUL IN Sixteen men from the Coast Artillery are CAMP. assisting John Hays Hammond, Jr., in his After one complete year of thorough with a wireless -controlled tor- searching, the National Volunteer Emer- Radio Station at Dyker Beach, N. V. Operated experiments by Experts of the National Volunteer Emergency pedo at Gloucester, Mass. gency Service, through its operators -Lieu- Service. Mr. Hammond will demonstrate his in- tenant Freeman and Private Schwartz -de- a Army and Navy require- ER are invited to visit the camp at Dyker vention before joint cided that the best outfit for camp this fall, as demanded by Congress. ments was that supplied by the Electro Im- Beach, Brooklyn, N.Y., and "listen in." board ADOLPH SCHWARTZ, A motor boat capable of thirty miles an porting Company. This set is one of their by wireless from and has served us Call 2 ASK. hour will be controlled Trans -Atlantic outfits aeroplane. almost as far as the name implies. Dyker Beach, Brooklyn, N.Y. an

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 507

CHARLES HILL'S RADIO bear are NAA, NAR and WCC., et cetera. ceiving set, consisting of a loose coupler, EQUIPMENT. CHARLES HILL. loading coil, two condensers and galena This photo of my wireless station shows Ligonier, Ind. dctector all mounted in and on a cabinet. the loose coupled 2,000 The transmitting outfit comprises Vi K.W. tuner of meters, Blitzen transformer, a Sayville rotary gap, 2,000 ohm 'phones, 1,000 meter loading coil, NAVAL RADIO SERVICE NOW condenser and galena "NAVAL COMMUNICATION hinge type oscillation transformer, glass fixed detector. I have plate condenser and key. SERVICE." These instruments, in connection with my Hereafter, the Naval Radio Scrviee will aerial, which is at present 40 feet high and be known as the Naval Communication 90 feet long, have enabled me to do ex- Service. Charges on all traffic exchanged cellent work. I am able to transmit 30 between other systems (radio, telegraph and miles in any weather and on good nights cable) and radio stations (ship and shore) can cover between 50 and 60 miles. At operated by the Navy will be accounted for times last winter I have been heard at the by the Naval Communication Service. Iowa State College Station at Iowa City, In addition to his other duties, the Di- which is a distance of about 100 miles. , ' ". rector Naval Communications will perform My receiving range incudes 9ZS, 9BC, the duties formerly assigned to the Super- . 9YA, 9YI, 9QF, 9IN, 9KI), and at times ... intendent Naval Radio Service. have heard Key West, Fla. I am a member Correspondence relating to the Naval of the United Radio Relay League and have d Communication Service should be addressed to Director Naval Communications. Radio, Charles Hill and His Radio Apparatus with be He Long Distance Stations. Va. Remittances should made pavablc to Which Hears Many Naval Communication Service. If used, money orders should be drawn on Post- just recently enclosed my receiving set in master, Washington, D.C. Commander 1). the cabinet. The two switches to the left W. Todd, U.S.N., has been transferred of cabinet are the primary switches; below from the command of the U.S.S. Dixie to there can be seen a 400 meter dead-end Director Naval Communications. Captain switch. W. H. G. Bullard, U.S.N., formerly super- The secondary switch is at the right of intendent at Radio, Va., has been placed in the cabinet, below is the secondary slider. command of the U.S.S. Arkansas. The loading coil switch is between the secondary and primary switches. The galena Hongkong, China, has a wireless station detector is mounted on a small door which with a radius of from 500 to 700 miles in can be closed when the detector is adjusted. daytime and more than 1,300 miles at For sending, I am temporarily using a re- night. lay which I transformed into a high -tone George Hammond and His Ambitious Looking buzzer until I complete a % K.W. trans- RADIO APPARATUS OF GEORGE R. Radio Laboratory. former which I now have started to build. My aerial consists of two stranded copper HAMMOND. wires, 4 feet apart, 150 feet long and 50 The receiving set of my radio station is applied for a government amateur license. feet high. as follows : 3,000 meter loose coupler with My call at present is GRH. I have had very good results with this fixed condenser, galena detector and Su- GEORGE R. HAMMOND. station. Some of the principal stations I perior 'phones. I also use a compact re- Oelwein, Iowa. Amateur News The South Jersey Radio Association. Hawkeye Radio Association News. Now "Bugs" for the Yorkville Radio On June 12, 1916, a number of the Amateur The Hawkeye Radio Association, Iowa's booming Development Association. Operators of south Jersey headed by Mr. C. Walde wireless organization, had a big exhibit at the Iowa Fair, held at August Now "Bugs" for the Yorkville Radio Develop- Bachelor, Wm. G. Phillips, Harry D. Densham, State Des Moines, ment Association. and Geo. E. Haldeman, met and organized the twenty -three to September one, inclusive. A very This organization since its large antenna was erected, which with the modern establishment has grown lustily and now has a South Jersey Radio Association, with headquarters membership at Collingswood, New Jersey, the following officers apparatus in the exhibit, enabled them to receive of sixty -three. It might as well be of one year: President, from all the high- powered stations in this hemi- said that the position of Secretary has changed being elected for a term bands several times, because the Secretary usually C. Waldo Bachelor; vice -president, George E. Hal- sphere, as well as those on the continent. Heter- deman; Treasurer, Wm. G. Phillips; Secretary, odyne receivers and all the latest apparatus were complains of throat trouble after going through on exhibit and gladly explained. Complete trans- the roll call half -way. Most of the members be- Harry W. Densham. came such only through At the present time the organization is well mitters were installed and working during the reading the columns of under way and is affiliating with all the smaller Fair under a special license. QST reports, etc., THE ELECTRICAL EXPERIMENTER. the ob- were sent out daily. It might be remembered that the Y.R.D.A. had associations throughout the state with a write-up in ject of forming a strong body to combat any detri- During the week of the State Fair the annual the February issue of THE Etec- form convention of the club was held at the Y.M.C.A. TRICAL EXPERIMENTER. Well, the Y.R.D.A. ob- mental legislation that may come up and to tamed members efficient relay service throughout the state. building at Des Moines. Lectures, talks, etc., were fifty through that write -up, which an given by various members and a "Round Table" illustrates the enormous popularity of The E. E. All clubs wishing to become members of the with Radio Association should communi- held. Also the members chose their officers for the scientific men of the country. As the South Jersey year and conducted all necessary busi- membership has risen to the maximum (sixty - cate with Harry W. Densham, secretary, Collins- the coming three), N.J. ness. Every radio enthusiast in the State of it will be impossible to enlist any more wood, Iowa was cordially invited to join this club. Any new members. The scientific work done by mem- further information will be gladly given. Address, bers in four months is given below: Arthur B. Church, Secretary, Lamoni, Iowa. February. -Mr. F. Smith, assistant to Joseph L. The Wireless Association of Pennsyl- Cermak, developed a ne3v chemical compound for use in electroion detectors. It will be put on vania. Dot and Dash Club of East Orange, N.J. the market shortly. The Wireless Association of Pennsylvania held March. -Mr. Joseph L. Cermak, E.E., made a its regular meeting recently. The past year was A Radio Club has been established under the combination of chlorine and another gas, which is one of the most successful for the Association. name of the "Dot and Dash Club" in East Orange, being successfully used to bleach discolored perl- The success of the organization is due to the N.J. The officers are: President, Charles Sum- mutter buttons. excellent work of the Technical Committee and mers; vice -president, Cortenay Whitman and sec- Messrs. Cermak, Smith and Goodman presented the interest displayed by the members. retary, F. F. Brothers. The purpose of the club the Naval Advisory Board with three inventions season is to promote interest in radio telegraphy. Dot - The work of the Committee in the past and Dash F. F. Brothers, secretary. namely, a land torpedo. an unsweepable mine and consisted mostly in the study of the "Vacuum Club, a projectile for use on Zeppelins. They were Bulb" as a detector and instructing the mem- thanked by the board for their services. bers in the requirements for securing Commercial May. -Inventions of small importance were Operators' Licenses. made by the following: The majority of the members possess sets RADIO CLUBS ATTENTION! a- Gas detector, Joseph L. Cermak. which are noted for their high efficiency and New mineral detector, F. Harvey. long distance work. The Association has the 3 Protection of aluminium- aerial wire from cor- advantage of having as members, men of high We are always pleased to hear s rosion, F. Smith. standing in the field of Radio activities, and a New Audion hook-up, T. Gerad. large number of Commercial operators and wide - from young Edisons and Radio Pocket radio set designed, B. F. Badrow. awake amateurs. Phone intensifying diaphragm, Joseph L. Cer- At the last meeting of the Board of Directors Clubs. Send a write -up of your mak. plans were formulated for the work of the Club with photos of members and Diminutive spark coil of great strength, Joseph coming year. An increased membership is de- L. Cermak. cided upon in order repay the Technical apparatus to -day to: Editor "Ama- This completes the work for May. As may be to observed, the officers and members have taken a Committee for its extensive research. teur News" Section, The Electri- very great interest in the work of developing the The Association has resumed work with lots radio art. of vim. The Secretary would favor any in- cal Experimenter, 233 Fulton St., The President, Mr. Joseph L. Cermak E.E. 73 formation or correspondence from similar or- New York City. East End Avenue, New York City, N.Y., will be ganizations. Robert E. Patchel, Secretary, 532 pleased to answer all inquiries regarding this S. Fifteenth St., Phila., Pa. Association's work.

www.americanradiohistory.com 5o8 THE ELECTRICAL EXPERIMENTER November, 1916

OFFICIAL LIST OF LICENSED RADIO AMATEURS NOT TO APPEAR UNTIL THE NEXT ANNUAL GOVERNMENT CALL BOOK. Amateur Radio Stations Licensed by the Bureau of Navigation During the Month of April, 1916. (Continued.)

EIGHTH nisrmcr- (Cont'd.) NINTH DmrIICr- (COnt'd.) Call Power Call Power signal Owner of station. Location of station. kilowatts. signal I Owner of station. Location of station. kilowatts. SAIZ Thornton, Wallace W 25S Madison Ave., Youngstown OAFO Harris, Harvey P 902 Burns St., Alton, Ill .5 Ohio .5 9AFE Howard, John C 311 S. State St., Champaign, Ill... 8AHS Walrath, Floyd E. DeKalb Junction, N. Y .5 91A Huckett, Edwin W 402 N. Oakley St., Kansas City,Mo. .5 SAFR Walser, Arthur L Chesaning, Mich .5 9AET Huff, Fred W 4328 Tracy Ave., Kansas City, Mo 8JQ Young Men's Christ. Ass'n 110 Fourth Ave., Ann Arbor, Mich 9AFA Jarossewics, Casimir 1330 W. 50th St., Chicago, Ill...... 5 9AFD Krus, Carl 4652 N. Hermitage Ave., Chicago, NINTH DISTRICT III .5 90E Andreen, Earl H 1204 Belknap St., Superior, Wise .5 9QA Larson, Lee H 2020 Telegraph Rd., Davenport, Ia. -.5 9AEP Avery, Norman K 307 Bigelow Ave., Peoria, Ill 9AER Marshall, Geo 2045 S. Lawrence Ave., Wichita 9RD Bailey, Frank M 525 Kenilworth Ct., Clinton, Iowa Kans. 9CQ Brhmer, Wm 1335 S. Kohn Ave., Chicago, Ill.. .5 9AEY Matsinger, Philip F 1956 W. 94th St., Chicago, Ill..... '.5 Buckley, Harold J 1206 Wrightwood Ave., Chicagoall. .5 9PJ Maxfield, David C. Le Roy, Minn 1 Brocksehmidt, Wesley E 173 Foote Ave., Bellevue, Ny .5 9TV Ostermeier, Cecil H. 529 W. Jefferson St., Springfield,Ill .5 9QH Blum, Sidney J 4105 Campbell St.,Kansas CityMO 9AFG Nevling, Lorin I. 4240 Maffitt Ave., St. Louis, Mo .5 9AGA Bornofska, Clar. & Elmer 1322 Lincoln St.. Racine. Wise .5 SAFR Phillips. Claude B Lucca N. D .5 9AEN Brewster, Vernon H Crystal Lake, Ill .5 9AEQ Richards, John 2508 Ames Ave., Omaha, Neb...... 5 9AFW Bechtold, Joe and Fred V North Manchester Ind. .5 9AFI Sprackling, Geo. A. 602 Milwaukee, Ave., Janesville, 9AFS Busey, Paul G 911 W. Nevada St., Urbana, Ill 1 Wis .5 9AEV Coffman, Scott 61 N. Gale St., Indianapolis, Ind 1 9AFM Swain, Raymond E 2828 Highland Pl., Indianapolis, 9AFD Clayton, Harold H R. F. D. No. 5, Monroeville, Ind .5 Ind .5 9NG Cramer, Wilbur R 5130 S. 40th St., Omaha. Neb .5 AFN Swanson, Martin 1900 Western Ave., Minneapolis, 9AEZ Egloff, Edward & Martin 2729 W. Barry Ave., Chicago, Ill 1 Minn .5 9AES Garrett, Hanle C 810 E. 40th St., Kansas City, Mo 1 OF Vollmar, Harold V 09 Wall St., Milwaukee, Wise...... 5 9BZ Goddard, C Shawnee, Kans .5 9AES Wareing. Thomas 2615 Seminary Ave., Chicago, Ill.. .5 9AEO hall, Alfred H 4015 Alcott St., Denver, Colo 1 9AFK Whitcomb, Donald L. 406 N. Lawndale St., Kansas City, 9AEU Haiti. Fred, Jr 3901 Fourth Ave., Sioux City, Iowa .5 Mo .5 9PB Hancock, Leveme 1209 13th St., Superior. Wise .5 9PU ilhelmy, Lino M. 18 S. Main St., Decatur, Ill. .5 Amateur Radio Stations Licensed by the Bureau of Navigation During the Month of May, 1916.

FIRST DISTRICT SECOND D1aratcr- (Cont'd.) Call Power Call Power signal Owner of station. Location of station. kilowatts. signal Owner of station. Location of station. kilowatts.

IKR Anderson, Andrew R . 29 Lewis St., Lynn, Mass. .5 AQS Bohman, Albert 122 Wilbur Ave., Long Island City, SDK Anderson, Herbert 833 Norman St., Bridgeport. Conn. .5 N. Y .5 1ES Armstrong, Leroy W 135 Point St. Providence, R. I...... 5 ARG Bona, Edward 82 Van Nostrand Ave., Jersey City, IJN Billotte, Louis C 10 Centennial Ave., Revere, Mass. N. J .5 IESV Ashland, Homer B. 76 N. Union St., Burlington, Vt... .5 ARN Bremer, Frank V 3613 Boulevard, Jersey City, N. J.. .5 1MZ Clark, Lyman J Cuttyhunk Light Station, Goewold, ARP Campbell. George C...... , 92 Highland Ave., Yonkers, N. Y.. Mass. .5 APY Charleston, Eugene E 1628 11th Ave., Brooklyn, N. Y .5 1SA Boy Scouts of America Cambridge, Mass. (License in name 2ARR Cohen, Monte 310 W. 14th St., New York, N. Y.. .5 Troop 2 of E. L. Gookin, Scoutmaster).. .5 2KA Coote, Charles W 588 177th St., New York, N. Y... 5 1UF Caldwell, Raymond P 18 Morton St., Providence, R. I... Public School No. 115. 1Á1D Caswell, Carlton T 106 Franklin St., Framingham, 2ARR Dickinson, Edwin A 1038 Garden St., Hoboken, N. J... .5 Mass. .5 2ARM Dimmick, E. Ray 230165 4th St., Jersey City, N. J... 1 1DH Cook, Lewis W 49 Pleasant St., Ansonia, Conn... .5 2PM Fanion, Adolph .1 Belle Harbor. N. Y IDO Cook, Witter T 460 W. Main St., Norwich, Conn.. .5 2ARC Ferguson, George M Stuyvesant Ave., Brooklyn, 1SB Corcoran. Thomas A.. Cambridge, Mass .5 303 . Y .5 IESW Dodge, William E ... Beverly, Mass. .5 2AQW Frankenstein, Edwin S 97 Bruce Ave., Yonkers, N. Y .5 LEST Eaton, Richard E 59 Lovett St., Beverly, Mass .5 2AQT Ferris, Clinton S 409 Smith St., Peekskill, N. Y 1 SNI Folin, George G 133 Buckminster St., Brookline, 2ARS Grecs, Joseph F 134 Manhattan Ave., Jersey City, Mass. .5 N. J .5 1ON Cosgrove, Roland D 14 Wright St., Cambridge, Mass... .5 2AQR Grover, Paul B Toma River. N. J 5 1N Davis, Orin F ... 124 Pearl St., Somerville. Mass.... 2AQT. Hall, Norman C 47 Hill St., Newark. N. J 5 1PD Folsom, Owen F 89 Hewlett St., Boston, Mass...... 5 2ART Hammond, George P 1855 70th St., Brooklyn, N. Y 5 INT Fruch, Frederick G 962 South St., Roslindale, Mass... .5 2AQQ Hoffman, Frank Keansburg, N. J .5 1SR Gray, Hollis L 99 Vine St., Medford, Mass...... 5 2APV Hymmen, Robert 100 Armstrong Ave., Jersey City, 1IT Hahn, P. Francis St. Anselms College, Manchester, N. J .5 N. H i 2ARW Jockers, Edwin B 142 Ridge St. Newark, N. J .5 1FII Ham, Miles F 21 Crosby St., Augusta, Me. 2APU Krantz, Hubert K 183 Argyle Rd., Brooklyn, N. Y .5 1Jß Harding, David W Vineyard Haven, Mass .5 2AQK Lambert, Fred F 300 Sickles Ave.,NewRoehelle,N.Y IESQ Hasbrouck, Louis 130 N. Plesant St., Amherst, Mass.. .5 Leiter, David 262 Delancey St., New York, N. Y .5 IOC Henry, Hugh M. Rochester. Vt .5 2ARK McCoy, Lester M. R. F. D. No. 2, Peekskill N. Y .5 1MN 'Iodation, Milo L 24 Wachusett St., Worcester, Mass. 2ARU Machlett, Raymond R 131 W. 188th St., New York, N. Y .5 1FW Holton, Albert M Il Florida St., Springfield, Mass... .5 2ARQ Miller, Raymond H 327 Hillside Ave., Newark. N. J 1AU Huntington, Charles E 3 Orange St., Newburyport, Mass 2KF Nolan, George T 449 E. 183d St., New York, N. Y 5 IDA ohnaon, Arthur A. Cromwell, Conn .5 2AED Oechler, Alfred C 82 Smith St., Irvington, N. J .5 FAH Kelly, Richard P S O St., South Boston, Mass .5 2ARI Fawley, Myron G 513 2nd Ave., Asbury Park, N. J .5 1DF Kelsey, Philip C Ivoryton, Conn 1 2ARL Perry, Irving D 68 N. Parkway, East Orange, N. J 1NZ Knight, George W 29 Central St., Manchester, Mass.. .5 2ARS Plauth, William 179 Euclid Ave., Brooklyn, N. Y 1LZ Knight, Montgomery 475 Appleton St., Holyoke, Mass.. 1 2ARH Randell, Edward J. Fort Totten, N. Y .5 IFL Larrabee, Charles W 176 Prospect St.. Portland, Me.... .5 2AQY Showalter. John W 333 Birch St., Richmond Hill,N.Y .5 1JA Leathers, John W 78 Bay State Ave., Somerville, 2AQQ Smith, E. Carter 572 W. 187th St., New York, N. Y .5 Mass .5 2AQV Sommer, Isidor 56 Columbia St. , New York, N. Y .5 1PQ Leavitt Vernal A. 06 Lafayette St., Portland, Me .5 ARE Southard Sealey M 32 Raynor St., Freeport,ort, N. Y .5 IMR Leonard, Frederick D 353 S. Main St.. Mansfield, Mass.. .5 APW Vanderbilt, Harold W 205 Park Pl., Brooklyn, N. Y .5 .5 IESR Leonard, Theodore 1188 State St., Bridgeport. Coon... THIIiII DISTRICT IUT Marcroft, Jesse Warwick, R. I .5 LEY Marcroft, William 935 Northup St., Cranston, R. I .5 3VG Applegate. Franklin & 11%IC Murray, Albert F 21 Norway St., Boston, Mass .5 Macpherson 34 Hillcrest Ave., Trenton, N. J .5 Woodbine, 1 IND Mix, Donald G 1 Kensington Heights, Worcester, 3QT Bayard. Arnold N. J Mass. 3FT Biseiotti, Bernard J. 608 Carpenter St., Philadelphia, Pa . 5 INN Plaisted. Frank II 142 Davis Ave., Brookline, Mass.. .5 3ATN Briscoe, James D Hyattsville, Md .5 1ST Reynolds, J. Louis 20 Gordon St., Framingham, Mass. .5 3VB Butt, Harvey R. 1307 Moran Ave., Norfolk. Va...... 5 1GE Reynolds, William B 37 State St., Framingham Center, 3AEA Craigie, Stuart M 511 W. Grace St., Richmond, Va. .5 Mass .5 3AEW Dicks, Grover C Hagerstown, Md .5 2430 St., Harrisburg, Pa I Rhodes, Clarence A . 50 Sedgewick St., Bridgeport, Conn. .5 3ADR Endress, John N Jefferson 1ADEN Rosen, Victor E 33 Woodlawn St., Lynn, Mass...... 5 3AHI Giles, Larkin 1307 Clayton St., Wilmington, Del .5 1UW Rowe, Austin E 110 Loring Rd., Winthrop, Mass.... 1 AD Harrell, Leonard B. 900 Holladay St., Portsmouth, Va .5 11M nay, Charles T Saugus High School, Saugus, Mass. 1 3PV Hiestand, Benjamin Marietta, Pa .5 1IV herman, Israel 55 Revere St., Boston, Mass .5 3AAB Lansford, Willis R. 3607 13th St., N. W., Washington, 1VN .outhworth, Palmer H..... 34 Dlontowese St., Hartford, Conn D. C .5 1FY Stevens, Charles R 30 Worcester St., Framingham Lever, Haseltine S Abington. Pa .5 Center, Mass .5 3ADE Layton, Howard H 805 Washington St., Wilmington, Walter A t Thurston St., Somerville, Mass.. .5 Del 10D Taylor, .5 1KZ Valdie, Thomas G. 1 Woodbury St., Beverly, Mass.... .5 3DY Lynn, Thomas H Hyattsville, Md Walker, J. Frank Kittery, Me .5 3SJ McIntosh, Howard F 4218 Thompson St., Philadelphia, 1JW Pa 5 SECOND DISTRICT 3TS Mandeville, Francis T 116 Church St., Boonton, N. J.... .5 Baltimore, 2AQQ Alexander. Bronson H.... 600 W. 183d St., New York, N. Y.. .5 3RK Mecaslin, Harry B 3903 Hawthorne Ave., 2ARF Allen, Edwin W., and Md 1 James J., Jr Chatham, N. J .5 ATM Morgan, Joseph, Jr 408 Tioga St , Johnstown, Pa...... 1 2ARV Appell, Daniel T 41 St. Nicholas Ter., New York, IO Morgan, Joseph, Jr 314 W. Seymour St., Germantown, N. Y .5 Pa .5 2APE Averill, William H Sayville, N. J AEK Lewis, Samuel W 121 -B North Mass. Ave., Atlanti 2ARA Balison. Howard 361 Eastern Parkway, Brooklyn City, N. J .5 N. Y .5 3MY Moyer, Edgar F 561 Broad St., Emaus, Pa .5 2AQP Bargebuhr, Herbert M 649 W. 184th St., New York, N. Y .5 3ADG Roelim, Sewall 501 Upland Ave., Noble, Pa .5 Continued on opposite page.

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 509 OFFICIAL LIST OF LICENSED RADIO AMATEURS NOT TO APPEAR UNTIL THE NEXT ANNUAL GOVERNMENT CALL BOOK. Amateur Radio Stations Licensed by the Bureau of Nav'gation During the Month of May, 1916. (Continued.) THIRD DISTRICT- (Coned.) EIGHTH niwrRIrr- (Cont'd.) Call Power Call Power signal Owner of station. Location of station. kilowatts. signal Owner of station. Location of station. kilowatts.

3AP Seheeta, Edwin F Wyneote, Pa. .5 BASE Flory, Carl L 119 W. Decatur St., Eaton, Ohio.. .5 3GY Swinney, Walter, Jr. 815 N. Mount St., Baltimore, Md.. .5 SASN Fisk, Rufus 98 Park Ave., Binghamton, N. Y... .5 3TF Thorborg, Martin E MO Seymour St., Philadelphia, Pa. .5 8ASP Gamble, IIoward B. 2537 E. 128th St., Cleveland, Ohio. 1 Twine. Roy W 319 W. 28th St., Norfolk, Va 1 8A ' Greenwell, Robert 6302 Utica St., Cleveland, Ohio... 1 3ATK Vicesman, Warren 2711 Twoly Ave., Baltimore, Md .5 8AD liantman, Alexander 21 Vine St., Pittsburgh, Pa. 1 3ADW Walker, Orville R. 134 S. 17th St., Allentown, Pa .5 HAGS Hart, 1. Bruce 1215 S. Arch Ave., Alliance, O...... 5 BAIL Wallace, M. Edgar 38 Prospect St., Trenton, N. J 1 8AST Hills, Harold C Palermo, N. Y .5 SAGA Weikel, John H 900 Church St., North Wales. Pa .5 8ASG Howsare, George D...... 119 W. Decatur St., Eaton, 0 .5 3AGD Westlake, Harry T 1922 N. Broad St., Philadelphia,Pa .5 8AKA Kepler, Ralph E 210 Allen St., Dayton, O 5 3BR Witty, Gustav 1608 W. Allegheny St., Philadel- Kidd, J. Wm. 606 Cherry St., Niles, O 1 phia, Pa 1 SAJN Knott, Charles E 107 Stedman, Sayre, Pa l SAAR Wohlsen, Richard 430 W. Orange St., Lancaster, Pa 1 8ASA Lininner, Clarence R...... 614 N. Broad St., Ridgway, Pa 1 3RS Yearley, Clifton K. Garrison and Feruhill Aves., Balti- SASS Millspaugh, Frederick 37 Gaylord St., Binghamton, N. Y. .5 more, Md 1 SACK Morns, Carleton D. 31 Monroe St., Monroeville, O.... .5 SATO Zapp, Frederick A. ,469 Rutherford St., Trenton, N. Z .5 SASS Ulney, Clarke 28 Roxford ltd., E. Cleveland, O... 5 FOURTH DISTRICT BASK Paul, George 2950 E. 57th St., Cleveland, 0.... 8ASL Proutey, Laurence 175 De Hussey St., Binghamton, 4DX Bening, Broughton W.... 50 Whiteford Ave., Atlanta, Ga .5 N. Y .5 Elston, Esmond 13 '27 5th St., S., St. Petersburg, Fla. 1 8AST Roe, Millard J 909 Egleston Ave., Kalamaaoo, 4EB Barney, Owen J Nasareth, N. C .5 Mich. .5 4CG Holtaclaw, Ralph C Roseland, Fla .5 8ASW Sager, Merel 44 Apple St., Tiffin, 0 .5 4EA Huggins, William C 7 S. 4th St., Wilmington, N. C.... 1 BAEE Schmid, Paul J '21 Main St., Columbus, O .5 4DY Raft, James H Bay Shore Boulevard, Tampa, Fla. 1 GARY Spitler, Stephen ontinental, O .5 4CA Shaham, J. Hubert 315 W. 5th St., Rome, Ga 1 BASF Stolsenbach, Robert W. 4EC Shumate, John R., Jr t300 Clay St., Thomasville, Ga..... 1 and Charles H 24 W. Market St., Lima, O 4DZ Stone, Hector A Lockhart, Fla. .5 Stybr, Gilbert R. F. D. No. 3, Bellevue, Pu...... 5 FIFTH Manner 88AADR Sullcharger, John A 1412 Woodbourne Ave., Pittsburgh, Dawty, Albert 5918 Iaurel St., New Orleans, La.. .5 Pa .5 5EP Fort, Fred A 2222 Portland Ave., Shreveport,La, .5 The Electro -Set Co 3200 Franklin Ave., Cleveland, O. 1 5EN Harrison, W. Mace 100.3 Elgin Ave., Muskogee, Okla... .5 SASM Terry, Donald M Scott, O .5 5E0 Mottashed, Marvin H 3126 Lillian St., Shreveport, La... .5 8FX Thomas, Norman A 512 7th St. Marietta, O .5 HARZ Wilson, Harold H. Silver Creek, N. Y .5 SIXTH DISTRICT SASU Yotter, Francis P (Freeport, Pa .5 6RQ Abrahamson, Ray 4220 California St., San Francisco, Cal .5 NINTH DISTRICT 60A Adams Eugene R. Mountain View, Cal. .5 P 662 SG, San Francisco, Altland, Corner Clayton Cal. 5 AGD Banks, Archie E. R. F. D. No. Iowa .5 Sante 2, Delmar, 6MQ Anderson, H Mayfield, Cal .5 AGW Barnett, Forrest 2015 Western Ave., Mattoon, Ill .5 601{ Becker, Peter J. 2722 Harvard Blvd., Los Angeles, IAGP Barrett, Paul G 3150 Central Ave., Indianapolis Cal .5 Ind .5 8VH Blackstone, Clifford M..... 1606 W. 50th St., Los Angeles, Cal. .5 9AGX Bean, Mason 521 E. High St., Jefferson City, Mo .5 6DA Bolton, Harold B 4300 Judah St., San Francisco, Cal. 5 9AGS Becker, Paul ltf 4427 Greenwood Ave., Chicago, Ill .5 6FY Boner, Perry 837 4th St., Santa Rosa, Cal. .5 9AIC Bliss. Sidney H 120 Jackman St., Janesville. Wis .5 Clark, Herbert 578 16th St., Oakland, Cal .5 9AGU Briscoe, Bertram O 848 La Salle St., Chicago, In- .5 Clewett. Heber H...... 1002 S. Reservoir St., Pomona,Cal. .5 9AGN Brittin, Frank L 1149 W. Edwards St., Springfield, Day, Elwin C 907 Valencia St., San Francisco,Cal. .5 Ill 1 6UV Faasett, Lee 4326 Balboa St., San Francisco, Cal. .5 9AGY Brodnax, Lewis M 3526 Walnut St., Kansas City, Mo 1 6PP Ferrill, Wm El Cajon, Cal .5 9AHU Donald N 3332 Kenmore Ave., Chicago, Ill .5 6FQ Foster, Harold M 030 Culver St., Orange. Cal. .5 9AHW Call, George R 1529 Pearl St., Sioux City, Iowa 1 6VG Fowler, L. Deane...... 1027 6th St., Redlands, Cal. .5 9AIA Campbell, Albert 4243 W. Congress St., Chicago, Ill .5 Hutchinson, Howard W.... 614 S. Brand Blvd., Glendale, Cal .5 9AGF Canary, Elmer B 810 E. North St.. Indianapolis, Ind .5 6CQ Kemper, Horace L 17314 Loma Drive, Los Angeles,Cal .5 9AIJ Cook, George S 1932 Penn. Ave., S., Minneapolis, BVJ Kinsman, Joseph W 3467 Arroyo Seco Ave., Los Angeles, Minn Cal. .5 9AGG Cottrell, Gorham J 1628 Jersey St., Quincy, Ill .5 6DR Laverty, Finley 5332 Abbott Pl., Los Angeles Cal. .5 9AGQ Davis, Herbert 6141 S. Kolbourne Ave., Chicago, Leigh, 827 2d St., Cal..... 1 6VF Philip 1'. Santa Monica, 1 6UR Link, Ralph L 1520 Aman Way, Los Angeles, Cal. .5 9AHK Drummond, Ralph Oglesby, Ill .5 6JJ Klahn, Leander 27 Chenery St. , San Francisco, Cal. .5 9AGZ Engel, Roman 664 48th St., Milwaukee, Wis .5 6MM Moore, Norval E . 652 E. Culver St., Orange, Cal.... .5 9AIF Fawcett, Lester S 206 3d Ave., S. W., Independence, 6TI O'Dell, James J 327 Post St., San Jose, Cal .5 San Iowa 680 Parkin, Gladys Kathleen... 22 Terra Dillo Ave., Rafael.Cal. .5 9AGH Fenner, Zell G 23 E. Washington St., Colfax, Iowa. 6QC Perry, Oliver A Meridian and Q St., San Diego,Cal. .5 PAIN Ferguson. Wm. B 108 N. 17th St., Richmond, Ind.. 6TK Robinson, Sidney E 2929 Broadway, Oakland, Cal...... 5 9AGV Fiedler, Herbert W 1142 Diversey Parkway, Chicago, 6DQ Sleeper, James L. . , 211 Orange Ave., Santa Ana, Cal.. .5 Ill. 6KZ Smith, Harold 3415 Glen Albyn Drive, Los PAGE Gamble, Glen A 4329 Burdette St., Omaha, Neb Angeles, Cal .5 9AHA Gates, George B 942 Superior St., Racine, Wis..... 6QN Snider, Wallace 2031 E. 1st St., Long Beach, Cal... 5 9AHT Glavin, Roland E 745 Lawndale Ave., South Bend, O W 1061 Oakland. Cal Summers, James 62d St., .5 Ind 1 6GQ Thurman, Alvin C. 7 Grant Ave., Watsonville, Cal .5 SAGO Groth, Wm. A. 1534 W. Locust St., Davenport, Ia. .5 Howard E Pomona, Cal. 6TC Wright, 315 Alvarada Court, .5 9AHE Harlin, Paige J 3704 S. Bryant Ave., Minneapolis, SEVENTH DISTRICT Minn .5 7KK Adams, Le Roi T 364 Monroe St., Portland, Ore.... .5 RF Harmegnies, Paul E 730 Wisconsin Ave., Oak Park, Ill. .5 70F Allard, Ambrose Evanston, Wyo .5 IDY Healy, Kent T 849 Willow St., Winnetka, Ill .5 7BU Barrel]. Dana A 839 W. Pennsylvania Ave., Med- Herrling, Raymond C 856 Prospect St.. Elgin, Ill .5 Stanley W. Glencoe, ford, Ore 1 9QE Hopkins, 520 Greenleaf Ave., Ill... .5 70K Bode, Hugo P 6315 Beacon Ave., Seattle, Wash.. .5 SAIL Howard, Chas. B 1712 E. Jackson St., Springfield, Ill. .5 7CV Clark. G. Warren Lents, Ore .5 PAU Iversen, - Reginald J 422 S. 16th Ave., Maywood. Ill... 7CA Crosby, Edward J 508 E. Sharp Ave., Spokane. Wash. .5 9AIK Jordan, Jacob Jefferson High School, Lafayette, 7CD De Lacy, Clinton 1906 South J St., Tacoma, Wash... .5 Ind. 7NB Duncan, Thomas W 802 Gerald Ave., Missoula, Mont.. .5 AGM Knodle, Almon S 1942 Talbott Ave., Indianapolis. 7CN Emigh, Charles 335 Grove St., Walla Walla, Wash. 1 Ind .5 7FS Horatman, Herschel J 807 4th St., La Grange, Ore. IRO Lethen, Edward 4312 Greenview Ave.. Chicago, Ill. .5 Jones. Paul Wheatland, Wyo. 5. I Ail Lipe, Corodon C 1243 W. Wood St., Decatur, Ill.,.. .5 7N1 Learned, George H Forest Grove, Ore .5 AID Lockhart, Ashton Casselton, N. D .5 7LQ Linsley, Harry Evanston, Wyo .5 9AIM Mackley, Harry A 420 Dechman Ave., Peoria, Ill 1 7LL Lunan, Leslie 806 South M St., Tacoma. Wash... .5 9AHD blase, Harold E '335 Hennepin Ave., Minneapolis, Lyman, Rollo ' 05 N. Ave., La Grande, Ore .5 Minn .5 7QN Moore, E. H Queen Anne High School, Seattle PAGE Messing, Marvin M 27 Shaffer St., Freeport, Ill .5 9AIH Morton, Charles E Wash 5 IAHI 520 Schwarte St., Edwardsville, Ill .5 7PK Palmer, Robert S. 1321 Columbia St.. Hood Rivcr.Ore. .5 Nelson, G. Adolph 5518 W. 8th St., Duluth, Minn.-.. 1.5 1V Olsen, Winard G 1454 7PL Patterson, Fred 865 Williams Ave., Portland, Ore.. 1 Pensacola Ave., Chicago, Ill 7JU Tuerck, John St., K 495 Harrison Portland, Ore.... .5 yunI1un111u1u1l11111 11u,1u1,.11u1uu,llul 7M0 Smith, George M. Eatonville, Wash .5 uu1111111111111111111111111III,111uu111IIluIIl1IIIIIIIIIIIIIIInIlnnnnunnll II mlllmmlullllmllnlllluuul11II1II1I11u1II1nuIIlllullllul1l1l1Illllnlllm Illlulllnllun1l,111 7UA Wallace, George H. Vancouver, Wash .5 7AU Wilkinson, Albert E Y. M. C. A. Bldg., Baker, Ore...... 5 EIGHTH DISTRICT Attention ! Radio Amateurs. 8ACR Atkinson, Ward I 95 Rutgers St., Rochester, N. Y .5 BAJU Bell, Charles H. 5153 Flower Ave., Cleveland, Ohio .5 DO you find this advance list of "Licensed Radio Amateurs" SAJG Braats, Eugene C. Lowellville, Ohio .5 published ASV Bratton, Harry B. Brecksville, Ohio .5 monthly of real benefit? If not, we would just as SSAEX Calkins, Norman 2136 W. 100th St., Cleveland, Ohio. .5 soon publish additional pages of other matter in the Radio, Con- Conner, Charles E 726 Clinton St., Kalamaaoo, Mich. .5 structor and How-to-make -it Sections. Now is your chance to 8ASO Carr, Irving E 1246 Roosevelt Ave., Flint, Mich.. .5 let us know which you prefer. us say MEG Cawley, Eugene H 301 Chestnut St., Dunmore, Pa.... .5 Just mail a postcard and SSASSV Davidson, Robert L 50 N. 3d St., Newark, Ohio .5 -"I do not want the list of "Licensed Amateurs continued" or Davis, Harold P. 2095 W. 87th St., Cleveland, Ohio. 1 "I do want the list of Licensed Amateurs continued." Address 8ASD Dunmore, Wallace P...... 218 Main St., Binghamton, N. Y .5 the Editor, 233 8A,9K Evans, Jack H 806 Bayridge Ave., Pittsburgh, Pa. .5 Fulton St., New York City. -si SASH Finegan, George W 494 Columbia Ave., 1 Rochester,N.Y III,IIIII, IIII, e (To be Continued)

www.americanradiohistory.com 510 THE ELECTRICAL EXPERIMENTER November, 1916 IR'RTE5T PAITENTS

Improved X -Ray Tube The sparks occur between the ex- Thermionic Amplifier and Rectifier The segmented disc rotary spark (No. 1,192.706; issued to Elihu posed plate rims in the open air and (No. 1,193,206; issued to Hendrik gap 7, of well -known pattern, serves Thompson.) occur usually jn proximity to the Johannes van der BM.) to control the frequency of the In this invention over -beating of draft tube, which is made of insula- An improvement in the filament spark note. The impulse ci rcuit 6, the focal spot, the part of the sur- ting material. Thus, the sparks are of a vacuum type amplifier and rec- is not oscillatory and oscillations face of the target or anticathode caused to take place evenly in so tifier, involving an arrangement take place only in the antenna cir- subjected to the bombardment of far as wear on the plates isi con- composed of mica strips, through cuit 2 and 3. The reservoir cir- the cathode rays is prevented by cerned, owing to the rotation of the cuit 20, helps to keep the energy successively renewing the target sur- complete element. distributed throughout the system face during the operation of the Moreover, this gap serves as a and to realize the highest possible tube, for example, by making the "resonance indicator" for when the efficiency. gap becomes noisy the circuits are not properly adjusted; when the tun- System of Wireless.Commur ication ing Is good the sparks occur near the (No. 1,194.066; issued tc John center of the plates and the noise Albert Proctor.) is a minimum. An improved system of rat io telegraphy, involving an impact excita - tion circuit containing a s pecially Electric Gasolene Gun designed A.C. generator, t s here (No. 1,192,839. Issued to Alonzo shown. To obtain the slowly rising, O. Armour) but abruptly falling, A.C. wave A new form of cannon utilizing form from the alternator, a special the energy of an explosive charge field pole arrangement is use d. For of gasolene and air for driving the instance, in the diagram ti e four shell out of the barrel. As becomes larger poles are the regular excit- clear from the illustration the gaso- ing ones, while the four smaller lene and compressed air are ad- field poles are of opposite ir agnetic mitted in appropriate quantities to target in the shape of a wheel or the explosion chamber at the breech disc and rotating the same in any of the cannon, and this mixture is way, as by external means or by the reaction of the rays striking the rim of /iiaiiii /HH//// the target tangentially. which the hea 'rig filament is threaded and thus undue expansion Electric Light for Phonographs of the filament element is reduced to a minimum. II Ï: (No. 1,193,825; issued to Clarence l/. _.'%óv. H. Roop.) This permits the filament to be This patent covers the use of a placed in the same, or approxi- miniature electric light attached to .B fr tank mately the same, plane as the grid. the phonograph reproducer head The ordinary construction involving the use of supporting springs and capable of being operated from ilUlllt-= a flashlight battery. A switch is tb for the filament has been found to Z...ri. provided, which, when pressed 4 result in a considerable amount of downward in a forward direction, teat breakage of the heated filament. of makes momentary contact lighting fired by an electric ignition spark This course refers to large, ther- the lamp for the replacing of plug, thus driving out the projec- mionic bulbs of high power rating. tile with great force. A suitable mechanism may be Fountain Pen Flashlight .wo used to facilitate the rapid reload- and combus- (No. 1,193,534; issued to Julius ing of the gun other Friedman and Joseph L. Friedman.) polarity. Hence, when an armature tible flaids may be used in lieu of A clever design inductor revolves in a clock -wise gasolene. of flashlight and manner, the wave form will be similar to that shown in the graph, resulting in an extremely clean -cut Photo -Play Orchestral Director oscillation wave in the radiator (an- (No. 1,194.517; issued to Stanley tenna) circuit with practically no W. Lawton.) reactive wave present, as becomes An ingenious idea involving the evident. use of a master musical direction B &Went /nt lot chart, to be made when the film - fountain pen combined. The bat- Radio Amplifier play is released by the producers. tery supplying current to the miniature lamp. mounted in the pen (No. 1,193,778; e)d to Al: red H. point, is placed back of a small re- erbe needles [then playing in the dark, movable tank containing the ink. etc.; when thrown backward it The lamp circuit is closed by a closes the circuit permanently until spring switch and a threaded sleeve thrown upward again. It is de- co- acting so as to depress the switch signed to be manufactured as a sep- button and keep it there. To open arate attachment. A very market- the lamp circuit the sleeve is able idea which can be sold at a threaded forward a few turns. A reasonable price. well executed idea but unless the pen barrel is quite large, it would seem difficult to arrange for a rea- Radio Spark Gap sonable supply of ink. (No. 1,192,909; issued to Fred H. ndll ,Kroger.) The inventor of this spark gap High Tension D. C. Radio Trans- for radio transmitting circuits mitter claims to obtain similar results to (No, 1,194,154; issued to Melville hose attainable with r e g u l a r Eastham.) quenched gaps. ' An interesting patent covering the use of a 2,500 volt D.C. generator which, with choke coils, forms

The theater operator places his perforatedperforated master chart around the drum here shown, and in each perforation a plug is inserted. The drum rotates synchronously with the rotation of the motion picture projector mechanism. An amplifier of well -know n form The various projecting plugs on in ended especially for inter tif ying the drum operate proper switches, the strength of received rai io sig- controlling electric lamps behind the na s. It involves the use of a high glass dial -board before the orchestra resistance, wireless telephc ne re- director. Each glass disk contains cé ver joined acoustically, s indi- the "key" word relating to the ca ed, to a sensitive carbon micro - forthcoming section of the picture phone. The microphone cor trols a and the kind of music that is to be an exciting circuit. This acts on low resistance, loud- speakin g tele- played to accompany it These a "reservoir - circuit." 20, and an phone receiver, fitted with horn. A small motor carries a fan "keys" represent such terms as al- impulse circuit 6. All of these cir- The receiver and microphc ne are blade, which projects a stream of legro, moderato, andante, adagio, cuits co -act to -produce radio fre- pivotally mounted in a cabi net, so air against the multiple metal plates tremolo, segue, pianissimo, forte, quency oscillations in the radiation that it may be rotated sic wly to of the gap, and also the motor car- drum, organ, etc. (antenna) circuit 2 and 3. different positions in order t favor ries a worm and connecting gears, the microphone action for d ifferent which rotate the complete gap unit. COPIES OF THE ABOVE PATENTS SUPPLIED AT 10c. EACH or various signal strengths.

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 511 Phoney Patents Under this heading are published electrical or mechanical ideas which then you haven't a smell of the Patent yet. After they have allowed our clever inventors, for reasons best known to themselves, have as yet the Patent, you must pay another $20.00 as a final fee. That's S40.00 I I not patented. We furthermore call attention to our celebrated Phoney WE PAY YOU $3.00 and grant you a Phoney Patent in the bargain Patent Offizz for the relief of all suffering daffy inventors in this country so you save $43.00 I I When sending in your Phoney Patent application, as well as for the entire universe. be sure that it is as daffy as a lovesick bat. The daffier, the bet- We are revolutionizing the Patent business and OFER YOU THREE ter. Simple sketches and a short description will help our staff of Phoney DOLLARS 153.00 FOR THE BEST PATENT. If u take your Phoney Patent examiners to issue a Phoney Patent on your invention in a Patent to Washington, they charge you $20.00 for the initial fee and jiffy.

PHONEY PATENT OFFIZZ O. de DÂMFLY, OF SWATTER, IR. SCANATARY FLY ERADAKATOR .0% No. .00% Swatifications of Paty dufoigrfi Patent Afflicted

To Whom at Night it Consarns: platinum plate 1. The hungry fly that crushing it beyond recognition. With the Know all mutts by these presents, that was lured to the kitchen lamps the cheese falling of the mallet, spring 27 comes in I, O. de Dámfly, a citizen of the City of and commences to devour it, its bodily contact with spring 28 and closes circuit, Swatter, in the State of Irritation, have weight causing contact 2 to be closed. This which rings bell 29, thus calling the house- conceived, devised and perfected a mech- starts motor 3, causing spool 4 to revolve wife or maid. She resets mallet and re- anism for annihilating annoying flies in a and wind up sky -blue pink silken cord 5, places plate 1 with a new one. Plate 1 is manner that is entirely painless to the vic- thus opening faucet 6. This starts water now immersed in a pan of whale's milk tim. motor 7, which rotates pulley 8, which that has been sweetened with powdered Owing to the compactness and unique- turns shaft thus rotating pulley 9 and extract of lemon seed in which it should ness of the Fly Eradakator, it is, when in- thence driving dynamo 10, which charges remain for thirteen hours. After this cruel, stalled, out of the way. It should be placed storage batteries 11 and 12. When these harsh treatment, it should be wrapped in in the vicinity of the kitchen sink. Owing to batteries are fully charged they light bulb waxed paper and buried in sandy loam to the wonderful sensitiveness of the selenium 13, causing selenium cells 14 and 15 to close a depth of fifteen feet. This lessens all cells, the window shades should be drawn circuits A and B. With the closing of cir- danger of infection from dangerous bac- so as to darken the room. Now stand with cuit B motor 16 is started, which turns teria which might be residing on the the right foot pointing toward the North pulley 17. This pulley unwinds a black crushed corpse.

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The Highly Ingenious "Scanatary Fly Eradakator" Perpetrated on a Long Suffering Public by one, Monsieur O. de Dimfly, of Swatter, Ir.

Star and the left pedal extremity pointing linen cord from pulley 18, causing the same In testimony hereof I afflict my illustri- in the direction of the Patagonian Desert to revolve and unwind lavender cotton ous name this 35th day of April B. C. 1313, (this is not an allusion to dessert) and the string 19, to which is tied a wool sponge just 13,213 years after Queen Aristobulus second joint of the briefest digit of the saturated with chloroform. The fumes (who had been ironing King Chedorlaom- left hand resting on the right side of the from the sponge permeate the atmosphere er's pink burlap pajamas) dropped the hot nasal protuberance. Having assumed the in the region of the unsuspecting fly and electric iron on her pet hyena Gibbechai, posture just described, softly but sweetly render the poor, innocent thing uncon- severely scalding its left eyebrow and caus- and clearly make a noise like a lump of scious. In the meanwhile, as circuit A was ing it, because of this grievous injury, to granulated sugar, a piece of Limburger closed motor 20 is started, thus rotating succumb to the ravages of that terrible cheese or an embarrassed, mortified stewed disk 21, on the edge of which is mounted disease, water on the brain. prune: A fly, on hearing these familiar cast shank 22. In end of is -tin this shank (Signed) O. de Dámfly, sounds, will be attracted to the kitchen, fastened a blue- tipped match; from the after which you may leave and pursue movement given it by the rotation of disk By his Attorney, Morgan C. Aldrich. further 21 is other work until notice. the match scratched on coarse sand- Witnesses : The contrivance is then operated as fol- paper 23 and ignites. This, in turn, ig- lows: A piece of Limburger cheese (pre- nites slow- burning fuse 24, which burns U. F. Athed. viously steeped in hard cider and then string 25, causing twenty -pound lead mal- O. Gohang. boiled in molasses) has been placed on let 26 to descend on unconscious fly, thus U. Ranother.

www.americanradiohistory.com 512 THE ELECTRICAL EXPERIMENTER November, 1916 i,` QUESTIONr- bOX This department is for the sole benefit of all electrical expcnmenters. Questions will be answered here for the benefit of all, but only matter of sufficient interest will be published. Rules under which questions will be answered: 1. Only three questions can be submitted to be answered. 2. Only one side of sheet to be written on; matter must be typewritten or else written in ink, no penciled matter considered. 3. Sketches, diagrams, etc., must be on separate sheets. Questions addressed to this department cannot be answered by mail free of charge. 4. If a quick answer is desired by mail, a nominal charge of 25 cents is made for each question. If the questions entail considerable research work or intricate calculations a special rate will be charged. Correspondents will be informed as to the fee before such questions are answered.

INTERRUPTER. trolling the amount of current consumed. measure 1x3 inches, properly insulated by (646.) Gustave Geier, West Hoboken, Q. 2. Would the above mentioned appa- 5 mil paraffine paper. This is the theo- New Jersey, asks: ratus, connected to a 2W -foot checker- retical capacity. The size should be about Q. 1. Could six volts, twenty amperes, board aerial, be suitable to transmit 50-75 doubled as the paper will not lie perfectly battery current be transformed into 110 miles? The aerial will be 58 feet high at flat. volts? one end and 30 feet at the other. Q. 2. How to construct a loading coil to A. 1. It is impossible to transform a di- A. 2. Under favorable weather conditions increase the wave length to 10,000 meters, rect current to a higher voltage. If you and with a properly tuned oscillating cir- with a tuning coil, 4,000 meters and a 75 employ an induction coil with an interrup- cuit you should cover the distance you men- foot aerial 50 feet high. ter, the primary of which should contain 200 tion. A. 2. The winding core should be 24 turns while the secondary 3,340 turns; it is inches long by 6 inches in diameter and then possible for you to obtain the required CONDENSER. fully wound with No. 24 B. & S. copper voltage. The form of current obtained at (649.) R. J. Liedel, Providence, Rhode magnet wire. the secondary would not be a direct current Island, inquires: but an unsymmetrical alternating one with Q. 1. If a condenser will be just as ef- BATTERY QUERY. an enormous decrease in current value. If ficient when placed in hot wax and allowed (651.) J. G. McKlane, Long Island City, this current is passed through a closed core to cool so as to form a solid block with asks: transformer, it would be possible for you condenser inside, compared to a condenser Q. 1. Where can I obtain a battery yield- to couvert it into a more nearly sinusoidal immersed in oil. ing 10 volts and 10 amperes? alternating current. A. 1. The condenser immersed in oil is A. 1. You can obtain this battery from Q. 2. What is the best interrupter, a mo- more efficient for the simple reason that any dealer in storage batteries. We would tor- driven segmental drum with brushes when the molten wax is poured into the advise you to refer to our advertising col- or a vibrating spring contact? mould in which the condenser is placed a umns for manufacturers of batteries and ii A. 2. The drum driven by a motor is certain amount of air is drawn in with the you write to them they will be pleased to the best type of interrupter between the wax, thus producing air pockets which re- quote you prices. two you mention, but not for all purposes. duce the insulating qualities of the whole, Q. 2. What is the pressure of the ocean at the following depths: 15 feet, 20 feet, WAVE LENGTHS. 25 feet? (647.) E. A. Simonds, New Orleans, A. 2. At 15 feet the pressure is about Louisiana, wishes to know: 621 pounds, at 20 feet, 828 pounds, and Q. 1. What is the wave length in meters at 25 feet, 10.35 pounds per square inch. of an "L" type aerial, 90 feet long, 50 feet FINAL CALL Q. 3. Which do you think the most sen- high? On November 1st, 1916, the sitive of the following detectors: de For- A. 1. Two hundred and fifty meters, if subscription price of "The Elec- est Audion, Audio -Tron, Electron Relay, made with four strands. trical Experimenter" advances Radioson, Crystaloi, Tel -Radion? Q. 2. is above figured? to as re- How the $1.50 in U. S. (Canada A. 3. The first three are about alike A. 2. The wave length of an aerial is de- and For- The three latter are eign $2.00.) gards sensitiveness. termined by knowing two factors; namely This is the last chance listed in their correct order of sensitivity. its inductance and capacity. These are de- to subscribe at the old rates ($1.00 termined either by calculation or actual in U. S.,Canada and Foreign $1.50). TIGHT AND LOOSE COUPLING. measurement. In the former case, the di- No subscription for more than (652.) Harold Olsen, Berkeley, Califor- mensions of the antenna must be known Five years at the old rate ac- and substituted in the following equation: nia, asks: cepted. THE PUBLISHERS. Q. 1. What is the essential difference be- W =59.6 vLx and tight coupling? Where :-W=wave lengths in meters tween loose coupling A. 1. In the former the energy trans- L= inductance in henries and secondary C= capacity in microfarads. formed between the primary is reduced by the greater separation of the to Question 1 was obtained The answer while in the latter it is increased from a curve which shows the wave length and if the condenser is connected to a high - coils, al- tension source it is liable to break down owing to the closeness of the coils. Tight of a four wire antenna, having different the employment titudes and lengths. The curve was plot- at the point where there is an air bubble. coupling usually involves is reason it is advisable to place ca- of an auto -transformer or single coil. ted from Dr. Austin's formulae and For this an enamel quite exact. pacity units in oil instead of in wax. The Q. 2. Give composition of well -known block condensers which are well suited for insulating copper wire and TRANSFORMER ON PULSATING sold on the market are made thoroughly to give a flexible instead of hard brittle CURRENT. efficient by forcing the insulating com- covering. (648.) Roland S. Stroup, Oklahoma, pound into a vacuum chamber in which the A. 2. We regret to say that we cannot wants to know: condenser is inserted. give the composition formula for coating Q. 1. If he can use a one -half K.W. Q. 2. Which aerial would you advise for copper wire with enamel, as these are kept transformer -coil and Gernsback electrolytic a K.W. transmitting set -an inverted confidential by the companies. We would / 1915, of interrupter to good advantage on a pulsat- "L" or a checker-board? refer you to the September, issue ing current, due to irregular speed of gen- A. 2. An inverted "L." this journal, wherein appears an article en- erator, with a maximum of 110 volts? Q. 3. Would a rotary gap be more effi- titled Enameled Magnet Wire, Its Prop- A. 1. You should have no trouble in op- cient if it was encased and air pumped into erties and Manufactt re by L. Earl Deane, erating your one -half K.W. transformer - the case to form a higher pressure? Briefly stated the bare copper wire passes coil with this interrupter on the pulsating A. 3. The latter would be more efficient from the spoof through the enamel tank, current. A little patience in adjusting the for larger power; the former for low pow- which is usually electrically heated: The interrupter will possibly be required be- er sets, such as one -sixth to one K.W. wire then runs vertically through an oven, fore obtaining the maximum results. The where it is baked at the proper tempera- current obtained at the secondary terminals LOADING COIL. ture. The oven is provided with electric will be alternating. If the transformer is (650.) C. E. S., Minnesota, wishes to fans to maintain the temperature even. built efficiently, it can be operated directly know: This process is repeated five times, five by the pulsating current without the use Q. 1. How to construct a receiving con- coats on a wire, even down to the number of the Interrupter. In the latter case a denser of about .0005 m.f. capacity. 40 B. & S. gauge. Each coat of enamel is suitable resistance or impedance should be A. 1. The condenser should be made of baked hard separately before the next coat inserted in the primary circuit for con- 2 sheets of tinfoil, each of which should (Continued on page 516)

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 513

BARON MÜNCHHAUSEN'S NEW canal. It was explained to us that this new MEETING OF THE INSTITUTE SCIENTIFIC ADVENTURES. waterway was to be only a "small ' lateral OF RADIO ENGINEERS. affair, "but" 600 miles long and four miles At the recent meeting of the Institute (Continued from page 487) wide, connecting two of the larger canals of Radio Engineers held at the Societies' were when the Martian waterways theory together. This particular canal was to Building on September sixth, two very in- was first expounded by Professor Percival open up new fertile territory through an teresting papers were presented -one on Lowell. Lowell, of course, was right when existing part of a desert, by supplying the Ground Antennae, given by Leonard F. he stated that the Martian Canals were im- lands along its banks with water. Fuller, chief electrical engineer of the Fed- mense artificial waterways, crisscrossing Floating at a height of about 3,000 feet eral Telegraph Co., and which gave full the face of the thirsting planet. As there we observed miles and miles of the new, details of some of the experiments conduct- is practically no rain on Mars, Lowell rea- already -completed, but as yet waterless, ed in 1913 by his company, under his di- soned correctly that the canals brought the canal stretching to the horizon. The canal rection. waters from the melting Aretie snow -caps, was perfectly straight as if laid out with These experiments were of a somewhat to the temperate as well as the tropical rule and pencil. unusual nature, inasmuch as polar graphs zones, thus furnishing the planet with its In front and below us we saw the strange were used for plotting the current values only possible water supply. During one agency that "dug" the canal with a rapid- registered at the receiving station. A typi- season the waters would move from North ity that was as disconcerting as it was un- cal curve showing the intensity of received to South, during the next season from canny. Imagine immense metal latticed signals is shown in Fig. 1. This shows the South to North. Your mundane scientists towers over one thousand feet high roll- relation of two wires, one of which was had no fault to find with this theory, but ing forward on wide colossal wheels. And fixed, while the other rotated about an what they could not reconcile with their from the top of these towers you observe axis of 360 degrees. At the receiving sta- feeble intelligence was the tremendous di- bursting forth a broad purple electrochemi- tion a sensitive galvanometer was used mensions of these artificial waterways. cal emanation ray plying on the ground be- for indicating current values received at How could any living creatures. no mat- low in front of it. This ray, which has the that station. These currents were plotted ter how strong physically, build canals property of disintegrating the ground by in accordance with the rotation of the ro- 2,000 to 3,500 miles long and from six to breaking up atones of the desert sands, has tating wire about the 360 degrees. twenty miles wide? And not only one such immense inherent powers. The ground, Several curves were plotted with differ- gigantic canal, but hundreds of them! rocks, sands, etc., everything "melts" be- ent lengths of wire and the particular one Such engineering feats surpassed all bounds fore it, as snow goes tip in steam before here shown gives a cardioid or heart -shaped of human understanding. It was simply an oxyhydrogen flame. curve. It will be seen that when the wire impossible. Some of your scientists, I well Of course, this ray is not hot in itself, was pointing 180 degrees away from the remember, even set up intricate calculations it simply reduces all objects to their very transmitter, that maximum current values demonstrating that it would take thousands atoms. It is a sort of atomic volatization were received at the receiving station. of years to construct such brobdingnagian effect-the rocks and sand simply vanish Several other graphs were illustrated to- canals, if dug by an army of shovelers! into thin air. The wheeled towers which gether with experimental data, some of Another demonstrated to his entire satis- advance at the rate of about fifteen miles faction, that to dig a water channel 3,000 an hour, never stop. Their rays eut miles long and twenty miles wide, using through the soil steadily and with an as- 5,000 of the monster Panama Canal pat- tonishing precision. But the rays do not tern steam shovels, would require at least penetrate deeply, their adjustment being 500 years of uninterrupted effort! such that the depth of the finished canal I must admit, that when I first read those measures but ten feet. No waterways on figures on earth, I was much impressed and Mars are more than twenty -five feet deep, began myself to doubt Lowell's theory. But for they are used solely for the transporta- you see, the great trouble with us humans tion of water, no ships or vessels of any Is that we always compare everything to kind ever appearing on a canal. our existing means, never thinking what Of course, you will ask immediately, superior intelligence might accomplish with "What becomes of the 'excavated' material? means unknown to us. Everything is Though 'volatilized' atomically, it still must termed impossible because it is not under- needs exist for in Nature nothing is ever stood at once. lost." Necessity is the mother of invention on The answer is simple. Take water for Mars as well as on earth. If a great and example. If you decompose a gallon of it ancient people of a highly advanced civili- by electrolysis, it vanishes completely. Nat- zation see death staring them in the face urally it has not become lost, it has merely Graphical Curve of Activity for a Ground An- tenna as described by L. F. Fuller of the Federal because of the rapidly dwindling water been transformed into its chemical equiva- Telegraph Co. supply, you may rest assured that such a lents, i.e., two gases -oxygen and hydrogen. people will employ its best talent towards While you on earth know how to split which has already been published in pre- warding off such disaster in the face of up the water in its two equivalent gases by vious issues of THE ELECTRICAL EXPERI- insurmountable difficulties, even in the face means of electricity, you have not as yet MENTER. of inexorable nature. succeeded in disintegrating water by break- The second paper was presented by Prof. I have since satisfied myself that the ing up its atoms. Decomposing water, you Charles A.Culver of Beloit's College, Cam- Martians are not going to die of thirst for see, is but a crude mechanical process. It bridge, Mass., which dealt with the subject centuries to come. I have also noted with is as if you had cut an ear of corn into two of Radiation from Horizontal Antennae. satisfaction how puny your most important portions by means of a knife; in this opera- He spoke particularly of the special antenna engineering feats are, such as the Panama tion you have not cut in two all the hun- constructed at the Cruft's High Tension Canal, when compared to a Martian wat- dreds of kernels (atoms). This, of course, Laboratory at Harvard University. The erway. When I think of your little steam - is but a homely analogy, but it serves quite antenna was designed in such a way that shovels which I called monsters while on well to illustrate the idea. it pointed to several different places at each earth, I am convulsed with laughter. They In breaking it up into atoms, matter is of which receiving instruments were in- seem so ridiculous, so childlike after what transformed into energy, consequently noth- stalled. I saw yesterday; a child's tin train, standing is lost. On Mars the secret of this Data was given for a transmitter oper- ing in front of one of your "Twentieth accomplishment is the purple electrochemi- ating on 1.9 K.W. and various details show- Century" fliers, could not be more foolish cal emanation rays, an invention several ing the amount of current radiated from by comparison. hundred years old on this planet. the antenna and the audibility factor at- You see the trouble with your scientists Upon touching the ground or sands the tained at the receiving station. Several and others was, they never considered that rays instantly break up the atoms of the tests were conducted and it has been found great canals eould be dug quite nicely with- minerals, which explode with a terrific hiss- that an ordinary straight antenna radiat- out shovels and steam engines. They ing noise, like escaping steam. The heat ing a current of 4.7 amperes to the anten- never thought of it, because they had never liberated by this process is so enormous na gave a maximum audibility of 37+. heard of it, hence it was, of course, im- that at the point of the ray's deepest pene- This experiment was conducted at 9.30 a.m. possible. You have probably seen an oxy- tration, the sand or ground is fused to a Both papers were followed by lengthy hydrogen flame at work, cutting through lava -like substance impervious to water discussions by Prof. J. Zenneck, Dr. Lee de a solid bar of steel as if it had been but- which the Martians termed Tos. That this Forest, Mr. Lockwood, Mr. Armstrong and ter. Well, this is what my first impres- is so is indeed fortunate. For, if the Mar- others. sion was when I saw a new canal under tians were merely employing a simple ex- The problem of radiation resistance of construction yesterday. cavating process, they would have to water- an antenna is still in its infancy and there The Planet Governor, our august host, proof the entire canal, to prevent the wa- is considerable research work to be carried after we had managed to make clear our ters from seeping into the sands. The rea- out in this direction. There is no doubt wish, conducted us in one of his gravi- son for this is very obvious. that the various radio amateurs can per- tational flyers towards the site of the new (Continwed on nape 5391 form useful experiments along this line.

www.americanradiohistory.com 514 THE ELECTRICAL EXEPRIMENTER November, 1916 * * * * * ** * * * * * * * * * **** ** *** ** * * * * * * * ad i o c i te * "USE RADIOCITE IN YOUR DETECTOR AND FORGET IT" RADIOCITE is the most wonderful of all One of the important features of RADIOCITE radio crystals. It is more sensitive than is that it does not jar out easily. Each crystal Galena and far more sensitive than ANY is tested for sensitivity and guaranteed. RADIO - other crystal or mineral. RADIOCITE is a CITE comes packed separately in a box, wrap- specially selected grade of a rare crystal chemi- ped in tin -foil. Full directions accompany it. cally treated by RADIOCITE can our own secret pro- be mounted like cess. any other crystal; The mineral that WHAT IT IS it may be clamped looks like liquid gold. It has a highly and between springs, but it is best to set it in Hugo - wonderfully polished surface giving it a bur- nium soft metal. Money refunded if our claims nished appearance. This crystal is now in use are not substantiated. by several governments, and is conceded to be No. 3939. Generous piece of tested RADIO - the most satisfactory of all. It is used with a CITE. Prepaid, $0.50. medium stiff phosphor bronze spring, or with a THE ONE UP =TO =DATE MINERAL stiff silver wire, about No. 30 B. R. S. Gauge. WHICH EVERY AMATEUR MUST HAVE

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www.americanradiohistory.com November, 1916 ELECTRICAL EXPERIMENTER 515 ******************************`* * * * Ele ctro--Bes t. MADE IN AMERICA The "Electro" Rheostat -Regulator The Pride of Every Amateur PORCELAIN BASE The "Electro" PATENTED FEB, 1, 1910 Rotary Variable The only Condensers Rheostat on the market Consider these features: with FIRST-THESE CON- Center Rotary DENSERS ARE THE Action. ONLY ONES MADE WITH A TRANSPAR- This little current CASE IN WHICH regulator.makes a 4n1- ENT uable addition to any OIL CAN BE USED wireless set where it WITHOUT IT LEAK. is used to regulate the battery current. ING. In this way the t:tPEIIAI,l.r W I T II condenser capacity can VACUUM DETECTORS. be increased FIVE TIMES. SECOND - With battery lamps IS it Is very valuable, THIS CONDENSER where it 18 used to THE ONLY ONE NOW prevent the lamps ON THE MARKET from burning out on account of too strong WITH CONNECTIONS a current, etc. AT THE BOTTOM. Cover is of highly pol- Advantages over other small rheostats: gradual and accurate regulation of ished hard ruber com- current; great current capacity; little beating, resistance coil air- cooled; no concealed parts; Impossible to get out of order. PORCELAIN BASE. CANNOT position with a large No. 9241 BERN OR CHAR. scale that is easily read. The wire used In tt Is regulator is the finest high resistance wire. It will posltively not rust. break nor bend, even under aoonetent load of 3 amperes. This we guarantee in every instance. The groove Which holds the spiral is No. 9240. " Electro" Rotary Variable Condenser, ( ) shaped (PATENTED), which makes it impossible for the coil to fall out or 17 Plates, size 4jNx3?ginches. become dislocated. Large hard rubber handle (1 inch in diameter) is pro- $2 vided, allowing rapid and smooth turning of switch blade. Shipping weight, 2 pounds. `tVV J50 Resistance is 10 ohms. Maximum caMrlty, 3 amperes continually; size, 4 inchesaches diameter, thickness of base 13116 inch. 9241. Condenser, C No. "Electro" Rotary Variable No. 5000. Rheostat -Regulator (patented). Price.... $0.60 43 Plates, size 4;80% inches,- $4.00 Shipping weight, 2 pounds. Shipping weight, 3 pounds. P

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1/2 inch THICK == WEIGHT 1,2 lb. _= 658 ILLUST. What Catalog No.16 Contains and Shore Wireless Stations, besides a * great many useful tables and formulas. * It contains the largest assortment of This valuable book is 7x 5% inches in * Wireless and electrical experimental size and h inch thick, and well bound. * apparatus shown in any catalog pub- II is sent free for 4e. to cover postage only. * lished. In addition are shown Com- mercial Wireless Sending and Receiving Some of the questions answered * in Cyclopedia Catalog No. 163 * Outfits, Electric Motors, Dynamos, Flashlights, Medical Batteries, High The Wireless Law of August 13, 1913. How to Receive Wireless Messages. Frequency Apparatus, Plating Outfits, Wireless. * * by How Far You Can Telephone Toys, Printing Presses, Tools, Sporting Wave Lengths of Principal Radio Stations. * Goods and the LARGEST Scientific How to Erect a Wireless Aerial. * Book section published. This book will How to Receive Time by Wireless. - How to Photograph Electrical * give you as much information as many Discharges. books that cost you $1.00 or more. It How to Experiment with Spark contains 658 illustrations, 2,000 articles, Coils. * How to Test Storage Bat- complete Code Chart of Morse, Conti- teries. nental and Navy Codes, sixteen-page How to Make Tesla * "TREATISE ON WIRELESS TEL- Experiments. Electro Importing EGRAPHY," list of Call Letters of U. Call Letters of all Coto-, Co., merciai and Gov- 236 Fulton Street, New York City. * S. Government and Commercial Ship' Size 7x51; ". -2000 Articles erument Wireless Ap Stations. II I enclose herewith 4 cents in stamps ` or coin f or which please send me your * latest Cyclopedia Catalog No. 16 coo- staming 275 pages, 658 illustrations and Importing Co., diagrams, including Treatise on Wireless * Electro.. A Telegraphy, complete list of all U. S. Wire - a less Call Letters, and 20 coupons for your 160 page Free Wireless Course in 20 lessons. * 236 Fill t on S t., N. Y. E.E li * Name ********************Letddtess yes benefit by mentioning "The Electrical Experimenter" when writing to advertisers.

www.americanradiohistory.com THE ELECTRICAL EXPERIMENTER November, 1916

QUESTION BOX. and 234 inches in diameter, wound for 114 (Continued from page 512) inches of its length with No. 23 B. & S. gauge enameled magnet wire, and provided is applied. The finished wire is run off with a single slider? Would it increase the THE on to spools. Q. 3. Is the Trust holding back the supply of copper, or is there not enough cop- CRYSTALOI per to supply the demand for it? /nsu/o%r A. 3. There is not enough copper to sup- DETECTOR ply the enormous demand, hence the in- copper screening Rope or ore crease in price. 0n o//sides 1 BALSILLIE RADIO SYSTEM. (653.) J. Hanson, Washington, D.C., asks 11 for: %%'ç % 4i l`Oi:;; I Q. 1. A diagram of connection of the °iatíí¡:;P:;C; ;:¡i;¡: Balsillie system. A. 1. The diagram gives connections: . Vr;:r;;:í;r: %' S %' : %í :; The current of frequency 350 cycles is 1J r r: , i¡iÌV:1 taken from the rotary converter A. B is a l'''r,r choke coil. The transformer C, D, is an II` open magnetic circuit transformer. The gap ,' llh//r/I/1yI / I E is air -cooled with the object of pre- 1 I,r h venting the formation of an arc. F, G, and H are condensers. J and I are choke coils. It is a shock excitation system. Q. 2. What do you consider the best '// means of communication, by using either TYPE O the damped or undamped waves? Dimensions 2h "x 174" Price $3.50 A. 2. For short range transmission, o 654 Postage 10 cents the damped transmitter is far more efficient as Over 10,000 in use Type of Radio Antenna Suitable for Short -Range explained in one of our previous issues. Work. If you want a detector that is When employing a sustained wave appa- extremely sensitive and thor- ratus the current is being continually gen- efficiency of my set to ado another slider? a erated and emitted by the antenna and is A. 3. 560 meters. It would increase your oughly reliable, you need interrupted only when signals are sent out. tuning efficiency considerably by adding an- CRYSTALOI. Q. 3. Does the formula for the frequency other slider. Wireless Operators on land of an ordinary oscillating circuit cover the sea prefer the Crystaloi frequency of the Lepel systcr- SLATE AS AN INSULATOR. and A. 3. No. It has been found by Naysmith (655.)Charles W. Squires, Port Jeffer- for the reason that it is al- son, New York, inquires: ways ready. You have but Q. 1. What is the efficiency of the com- to turn the little wheel to pressed air gap as compared with a straight secure fine adjustment. and other gaps? A. 1. The compressed air gap is more ef- Guaranteed not to go dead or ficient than the ordinary straight open gap. lose its sensitivity. Q. 2. Is slate a good insulator? A prom- goods Send five cents for our miniature inent manufacturer of electrical catalog describing all types of Crys- states that it is not, at least not for cur- wireless apparatus. rents above 1,000 volts. At such a tension talois and other slate begins to "leak." EUGENE T. TURNEY CO., Inc. A. 2. Slate as an insulator is very poor. 2595 Third Avenue New York City However, it is extensively used on low voltage circuits not exceeding 300 to 500 volts potential. 0C1'>O4>C`0.41 . *a. h v G FREQUENCY CHANGER. EXPERIMENTERS!! (656.) P. Poulson, Atlanta, Georgia, WE SPECIALIZE IN t Diagram of Connections in the Balsillie Radio to know: System. wishes t SEAMLESS CARDBOARD TUBING 0 Q. 1. What is the inductance of a choke IN SIZES SUITABLE FOR that the Lepel circuit obeyed the follow- coil having 400 turns. the iron core being so TUNING COILS, LOOSE COUPLERS, ing equation: 60 cms. long and of 300 sq. cms. cross -sec- TESLA COILS, Etc. <.> tional area? Kindly tell me how you ob- C> SPECIAL GRAY TUBES 1 1 lad2 tain the result. I/3"a6% "a6%" $i ea. i8 "871¡ "873" sl ea. N .- 0. 2* LC 4L212 A. 1. The equation for the inductance of PRICE LIST a choke coil is: Smooth Wound Wireless Tubes where N= frequency Outside Lath. Price Per, GENERAL INFORMATION co : 1.26 N 8uA .o Os,,. Post 1= length of arc These pricesinelude PARCEL 1081 x755.12 .18 POST CHARGES: and are ao constant 3 shipped at once on receipt of 4, d= depending on the met- and remittance. al of where : number of turns '.-> 355 x 7 ' .12 .18 order

www.americanradiohistory.com November, 19 i6 THE ELECTRICAL EXPERIMENTER THE ELECTRO -SET CO. THE BIC SQUARE SUPPLY HOUSE FOR EXPERIMENTERS BRIGHT YOUNG MEN AND STAID OLD COLLEGE PRO- FESSORS ALL JOIN IN PRAISING OUR METHODS THESE BRIGHT here are smile random Il ;Nldllitliials- huudrttis wore just like them in our lilts. 'l'Iwy should convince you. EFFICIENT QUARTERS From Arthur R. Birkibs, Bronx - From H. F. Buckingham, Mon- From Albert A. Munch, Pitts- ENABLE US ville. N. Y. roeville, Ohio. burg, Pa. Dear Sirs: You certainly sent the Gentlemen: I purchased one of Gentlemen: Just a few lines to ex- goods very quickly. The Galena your one -half -inch spark coils, and press my gratitude for the way TO TAKE CARE OF YOU and silicon am the most sensitive it will give a three- fourth inch you handled my order. I have minerals I ever chanced to use. spark with ease, and have sent dealt with quite n few wireless They arc sensitive all over. Your ten miles with sane. concerns, but only one has come catalogue has the most complete up to your standard, and none line electrical From John Doering, Rock Island, of wireless and Ill. above it. I wrote you a card on goods I ever saw. receipt. of the Insulators and Guy Gentlemen: I am writing you this letter you Wire asking you to rush the re- From Forrest Adams, Shawnee, to thank for the mainder of the shipment through Okla. kind attention you showed. I received and I was astounded when I Gentlemen: Received your the package contaMing found the Wire other catalogue and it sure has some the brass rod and other material and the yesterday. By your in Insulator upon my arrival home. values in it. The raise in prices attention I am sure if are lower than in other catalogue this matter you have made me a the amateurs would raises. sìueerc friend and a booster for place one order with you, they your company. To show you the would be your steady customers. From Wm. Howard Gnrkencr, value of a good recommendation, Thanking you again for Electro- Brandon, Man., Can. I will say that it was the recom- Set Service, and hoping to have Gentlemen: I have received tho mendation from a fellow-experi- an order for you in the near MAILING AND EXPRESS m c:'.M Tele -Set and the Boy Scout menter that induced me to send future, I nm. Secret Service Writing Outfit. this order of mine to you. So I From Leonard Bnmbaucr, Erie, The writing outfit is something to still recommend your company to Pa. talk about. It works great and all my friends. Gentlemen:. I sent for a receiver so does the Tele -Set. From Wesley Gibbs, Rochester, last Monday and received it last From Bilgam, N. Thursday. I found same very George New York Y. satisfactory and I indorse your City. Dear Sirs: In the morning mail of goods highly. Gentlemen: As to your N. A. A. June 29th I received your postal very tested Galena: It cannot be saying that. the articles which I From Richard 'Clerk, Jr., New praised highly enough. There is ordered had been sent. I received York City. not a "dead' spot on the entire them in the afternoon. This was Dear Sirs: I will recommend your crystal and can assure you that I the promptest shipment I have company in every way possible am recommending it to my ever had. I am pleased with the for its promptness and efficiency friends. order. of material. HAVE YOU TRIED THE ELECTRO - SET CO. YET? CATALOG DEPARTMENT HERE'S THAT BIG RED HEAD WIRELESS RECEIVERS THE LAST WORD IN SENSITIVENESS Hand y By actual tcsl they arc from le to 27 point, uiore sensitive titan any other standard crake Book and A smut New York Testing Engineer reports i "' ., highly in favor of Red Head Receivers. You take 11%ItI, fi Catalogue no risk! 5 days' trial -and then if they do not rt.eu..d": fill everyexpeetation we send your money back. ', t 11_ HANDY1100K And the fas PRICES CATALOGUE clnating 2000 ohms, per pair, complete set, with head band and cord $5.00 "STORY OF 1000 ohms, single receiver only... .. 1.75 IOW) ohms, single set, with cord and band 3.00 11 QED HEAD 1 i. r! Send for our Free Booklet before buying wireless receivers RECEIVERS" lit ., vl_vV Or OUR RETAIL STORE Everybody that's inter- BIC TRIAL OFFER este d in Elec- To "Experimenter" Readers trical things Fur the purpose of further introducing needs these our already widely known super- sensi- tive Triple A Grade Wireless Min- beaks. erals, we offer for a limited time only Our Handy Book and Catalogue is this trial size package of A A A the finest thing of its kind pub- postpaid lished. pages of wó in th It contains many GALENA w upon re- invaluable experimental informa- t of loo in ns,.coin tion, tables, formulas, facts, figures T. and instructions on electrical and Nearly all serious wire- Send today for this trial package wireless less experimenters are of Famous Eleetroset Galeux. If things. familiar with our won- you do notri find more sensitive HiFIE.- v 128 Pages o1 Interesting Reading derful wireless minerals. spots in this small trial Describing hundreds of sleet rival Hundreds of testi- package than you can get out MAIL ORDER OFFICES instruments, wireless goods, motors, monials prove our con- of 8 oz. of ordinary galena, we toys, selenium cells, flashlights, raw tention that no min- will gladly return your dime. erals materials, parts, chemical sets, tele- marketed today NOTE: Do not confuse this offer graphs, bell, trains. lights, ete., all can compare in sen- with our regular Arlington Tested at lowest prices. sitiveness to our Individually Packed Galena at 25r standardized grades. postpaid. Each leek Costs Us 16e to Publish We Arlington Tested Gal- make an unlimited ena will be sent if requested upon We therefor ask that you send us guarantee that obviates t 10e M stamps or coin for your copy receipt of 25e in stamps or coin. all risk -Your money Arlington Galena is individually -lust to show that you're actually back if you are not festal for e,trrme distances midis interested -and also to partly de- satisfied. per-sensftive. fray the tremendous cost of thisbook. Send For The Bargain Trial Galena Today Positively no catalogue sent with- K1ß ;~ out this trifling remittance. Free -The. wonderful story of Red Head Wireless Receivers. Tells all about these superfine phones and THE ELECTRO -SET CO. how you can them 5 days with- try E LVIE W OF ONE STOCKROOMS out risk. Sent with carp copy of ADDRESS DEPT. -G CLEVELAND, OHIO OF OUR our Handy Book. SEND TODAY ELECTRICAL THINGS FOR EVERYBODY

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www.americanradiohistory.com 5 is THE ELECTRICAL EXPERIMENTER November, 1916

QUESTION BOX. (Continued from page 516) It Stands This Test! we get:- L- 1.26 x (400) s X 1500 X 300 108.x 60 YOU can short -circuit a THORDARSON Wireless Transformer right at the secondary terminals for fifteen minutes without damaging the transformer in Hence L=15.1 henries. the least. In fact, this is a regular test in the Thordarson laboratories. Q. 2. How would you connect two lead - aluminum, electrolytic rectifiers with a We do not know of any other transformer that will successfully withstand such transformer for doubling the fundamental an ordeal. It proves convincingly the quality that is built into the construction of frequent) supplying the transformer? A. 2. The diagram gives the connections you desire. It should be remembered that THE NEW the oscillating circuit must be tuned to twice the fundamentaL so as to bring the primary and secondary Into a resonant condition. Q. 3. What efficiency would I obtain from such an arrangement? THORDARSON A. 3. About 45 per cent at the most. WIRELESS TRANSFORMER

A new, perfected design -surpassing in range and flexibility our former models, with which operators have reported transmitting 1200 miles and over The Variable Shunt -an exclusive Thordarson feature- allows even greater flexibility than formerly. Locks in any position. New Ampere Scale accurately gauges the radiation. The new THORDARSON is very strongly built, of pressed steel, without a single casting. Comes completely assembled-no chance for mistakes or burn-outs. In five sizes, from % to 2jí kw., 10,000 -20,000 volts, any cycle desired. Hook -Up for Jump Spark Ignition Coil on Gaso- lene Engine, Operating on Either Dynamo or Storage Battery. Write today for full details and prices IGNITION COIL CONNECTIONS. Made by the Builders of the 1,000,000 -volt (657.) L. Kintoes, Sitka, Alaska, wishes: Transformer at the San Francisco Fair. Q. 1. A wiring diagram showing how a dynamo and storage battery are connected for ignition. 06 SO. JEFFERSON STREET A. 1. The diagram below Thordarson Electric Mfg. Co.,f shows the con- g CHICAGO, ILL. nections. Q. 2. Why is oil employed on top of the solution of a copper oxide primary battery? A. 2. The oil keeps outside dirt particles from entering the active electrolyte and prevents creeping of the battery salts. All copper oxide batteries use caustic potash, LENZITE WIRELESS DETECTOR or caustic soda as an electrolyte. If the P:,tenlcd May 2nd, 1916 oil d:d not shut it off from the atmosphere, the solution would spoil in a few hours.

THAUt.MAHK STEP-DOWN TRANSFORMER Recognized by leading DATA. (658.)Clarke Olney, East Cleveland, Ohio, authorities as most asks: the Q. 1. Is there any way of hooking up two 11\\:17/p or three single or double slide tuning coils sensitive and most effec- so as to make them as efficient as a loose coupler? tive Detector existing. If A. 1. The diagram herewith shows how i/ to connect a three slide tuner so as to give not satisfied, return same results equal to that of a loose coupler as far as tuning is concerned. and money will be refunded. Price: o, Detector complete Our patent protects us $5.00 and we protect you. ppellEm Write for booklet and 6558 Ef further information to Efficient Connection for Three Slide Tuning Coil in Radio Receiving Circuit. Q. 2. If so, would the wave length of LENZITE CRYSTAL CORPORATION the above be the combined wave length of 337 Chamber of Commerce Building Pasadena, California the included coils? A. 2. Yes. The wave length would depend also upon the size of the coils and upon the shunt capacities therein.

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www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER ',

Q. 3. Please give specifications for a small closed core transformer to reduce 110 volts A.C. to about 8 or 10 volts A.C. EffICIE NT5 fpR'- A. 3. The primary winding should consist of 500 turns of No. 36 insulated mag- 5.wa1tL7tq net wire. The secondary is wound with 40 sMIGNOaNY1S/lYSiEM EaUIPRP°SES turns of No. 16 wire. The iron circuit is made of laminated iron sheets of No. 21 °ly. ' ALL L'. & S. gauge and it should measure 5 "x3" 5Ap?..Awk outside. The windings should be properly insulated from the core. `r\ MICROPHONE. ASTE (659.) R. M. Jenkin, Wellington, New Zealand, wishes to know: Q. 1. What sort of microphone and relay would be most suitable for working surprise stunts, such as opening a door by merely speaking to it. Also where he could obtain such an instrument and the price. A. 1. In this kind of work it is necessary to employ a detectaphone transmitter. This can be obtained from the Micropho- Detec- tor Co., 119 Nassau Street, New York City. Watch for COAL TAR. 660.) P. Fisher, New York, N.Y., asks: LATEST Q. 1. What are the operations for making MIGNON coal tar? A. 1. Due to lack of space, it is impos- INVENTION sible for us to enter into details as to the coÑA°wavES NUUS in making of coal tar. The usual procedure Electrical is to place into a closed crucible a quanti- /WRITE FOR CATALOGUE Experimenter ty of soft coal and it is heated until the coal ANOr+ENnoN THE ELECTRICAL EXPERIMENTER tar starts to flow. This is drained from the bottom of the crucible by a suitable valve cock. The cover of the receptacle is fitted with an opening for permitting the gases to escape. These are very important factors, as most of the gasoline, benzine, Mignon naptha, etc., is removed from the gases after they have been properly condensed. SIZE OF CONDUCTORS VS. Adjustable VOLTAGE. (661.) P. Hallweck, San Francisco, Cali- fornia, wishes to know: Q. 1. What is the relation between the Disc Core cross -sectional area of electrical conductors and the voltage? A. 1. The cross -sectional area of a given conductor varies inversely with the voltage. Wave 2. in employ- Undamped Q. Is there any advantage ing an alternating current arc for radiotelephony instead of a direct current arc? A. 2. Very little can be said about the alternating current arc as a generator for Receptors sustained waves, as but little has been done in this direction. It may, however, be stated that the arc starts oscillating much more RW 1, RW 2 and RW 3 effic;ently, but we cannot tell off hand as to whether it proves to be more so when based on high power units. The subject is still THE LAST WORD IN RADIO ENGINEERING open for research. Q. 3. Describe the rotary field type of induction instrument. A. 3. The parts are arranged similar to those of watt meters, the necessary split phase being produced by dividing the cur- ELMIRA, N. Y., U. S. A. rent into two circuits; one of which is inductive and the other non- inductive. MOTOR QUERIES. (662.) L. Jackson, Indiana, wants to = New Undamped Wave Coupler No. 749 know: Q. 1. Some of the advantages and disad- Special Introductory Price, $18.00 vantages Our new coupler No. 79 Is 32' long, 9' wide. and of series motors. 10° high. over all, and on an average-sized Antenna A. 1. They are easily started, even tinder tunes to 15,000 meters. This coupler. used with the new CHAMBERS' SYSTEM or CIR- heavy loads. The winding is cheaper than CUIT. will bring in signalsfrom domestic the other types and the speed is nearer con- aril foreign Arc Stations surpristnglY loud and clear. Note the difference in stant than shunt motors when operated on size otour No. 748 and No. 749. constant current circuits. When used on We claim to be the original inventors of aSYSTEIII or CIRCUIT for the recep- constant pressure circuits such as those tion of the undamped waves without the employed for ihcandescent lighting, the use of Loading Coils or Osettlat trig Coils. as they are sometimes called : as with our speed will depend on the load. On no load SYSTEM or CIRCUIT only two Inductively they tend to race and will, if not watched. Coupled colts are necessary. Circuit supplied This CHAhaIIERS' CIRCUIT yno m tear themselves to pieces. Think of It! No extra coils to w for. and price i coupler only $1O on Place ordor now e to be i on the introductory enro. Orders filled in otatn n. Fend for Q. 2. In the operation of a motor what is riptive mutter. n the nature of the reverse (counter E..F. F. B. CHAMBERS & CO., 2046 Arch St., Phila., Pa. electromotive force) ? You bereft: by mentioning "The Electrical E.rperitnentcr" when writing to advertisers.

www.americanradiohistory.com 520 THE ELECTRICAL EXPERIMENTER November, 1916

A. 2. It is proportional to the velocity of rotation, the strength of the magnets and to the number and arrangement of the wires E3 E3 on the armature ; that is, the reverse Things You Need voltage depends on the rate at which the We list below a few of the many parts shown in our Catalog E, lines of force are cut. Q. 3. How may the rotation of a motor every experimenter will find use for. E be reversed? X KNOBS BRASS KNOBS A. 3. By reversing either the current whichSWITCH POINTS through the fields, or the current through ed )4í x ,1 D.z. 50 100 -^-. It j . E3 the armature. El g`p `- Lie ¡¡¡¡W' ' t No. 628 .30 .90 1.50 V (f '111 OHMMETER. I iiiiililliiiGI1 111 ' l'I Ol (663.) Pondy Elk, Pennsylvania, writes: Q. 1. What is an ohmmeter? T': B,f 802.... .,1[ -, A. 1. $ 32 "HOLE ' No.602.... Price$10 It is an instrument for measuring No. Price resistances 606.... $20 No. 626 .30 1.00 1.75 Doz.$I.00 directly where it is desirable Doz. to test with a high voltage. X X It consists of 0 -32 two parts, namely, a small hand dynamo EX ,,"x ," , :ri1ll8114I, EX capable of generating 100 volts or more, I and No. 627 .36 1.25 2.00 the instrument proper. The latter has 11 1.1 11111141/ two coils mounted at right angles to each E3 other and a magnetic needle, which takes a certain position between the two coils, ac- >c NICKELED SWITCH POINTSX10-32. Price cording to the relative currents in the coils. L12 Bt-suinc 50'o ADVANCE X No.601 .. Price S.04 No.608.... Price$OS E3X One coil is connected between the dynamo E3 Doz. $.40 We Make PROMPT SHIPMENTS on all of the Doz. $.50 and one terminal of the circuit whose re- C¡!1^i'',]tt above listed material. ryr':Tt sistance is to be measured. The other coil ON E3! . POSTAGE ALL APPARATUS EXTRA L__?JCK is connected in series with a high resist- MAGUIRE ance inside the instrument so as to form a & SHOTTON shunt across the main circuit, as shown in Albany, N. Y. XX7 the figure. When the dynamo is operated, fr- .jM Mj M the current divides, part going through the coil C and then through the main circuit, whose resistance is to be measured, while the remainder goes through the coil P and the high resistance R. The currents through the two coils are inversely propor- Two -Step Multi- Audi -Fons tional to the resistances in their circuits You don't know what wireless signals are until you have heard a Two -Step M. A. F. Circuits of Direct Reading Ohmmeter of the "Megger" Type. Multi -Audi -Fone - - - - $18.00 since the same voltage is applied to both, and With Special Head Set - - 23.00 therefore they attract the needle, cor- respondingly. For a given voltage of the Pocket Wireless Receiving dynamo, the attraction of the coil P is constant, while the attraction of coil C becomes Set 5.75 greater as the resistance in the main line M.A.F. Detector Stand - - 4.25 becomes less. The pointer attached to the needle will, therefore, move towards C, as M.A.F. Fixed Condenser - 2.00 the resistance in the line becomes less and Price $75.00 the scale may be divided to indicate the re- Un- Damped -Waver 45.00 & 100.00 sistance in the main circuit. Q. 2. For what ranges of resistance is SEND FOR NEW CIRCULAR Detector Fone - - - - 35.00 the ohmmeter suitable? A. 2. It will measure resistances from 275 MORRIS AVENUE N. about 5 megohms (5,000,000 ohms) down to MULTI -AUDI -FONE ELIZABETH, J. about 1,000 ohms. It is suitable in measuring the resistances of cable insulation, etc., besides many other things. NAVY THE NEW TUBULAR MICA COUPLER. MONOTONE (664.) Sigmund Schmeltzer, New York, CONDENSER IMPROVED QUENCHED GAP wants : Q. 1. Information on how to build the Navy type loose coupler. A. 1. We would refer you to the Sep- tember, 1915, issue of THE ELECTRICAL Ex- PERIMENTER for information concerning the Composed of n special mica possessing Infinitesimal Are you a leader or follower n adopting up- to -the- construction of a Navy type inductive coup- leakage. Its efficiency permits Use across your tuners minute efficient apparatus? Equip your station with ler. Full details given on a sep- in place of massive load coils, to raise wave. Use in the famous MONOTONE IMPROVED QUENCH- are there place of your present fixed condenser and note quality ED GAPS, which are a big mprovement over the arate blue -print supplement showing its of tone and amplification. Made In two capacities, original MONOTONE GAP Span that freak dis- one capacity for grid of audions and tubular detec- tance onpowerlul waves of RADIO ENERGY. Each construction. If you do not possess this tors, and one for orystal detectors. Individual capac- plate carefully machined. Best mica. Adjustable. copy, we can supply you with one for fif- One unit of the new gap for spark coils up to 3 ". On ity marked on same, tested from standard furnished of Spe- teen cents postpaid. by Bureau of Standards. Specify A unit for every It K.W. power transformer. purpose. highef- cially recommended for powers below t' K.W. Parts 2. I iciency, beautifully finished permanent eondenser, nickled and polished. You will be pleased with this Q. would like to know what instru- guaranteed. Postpaid $2.50 Each. new gap. Guaranteed. Postpaid $2.50 Each. ments to use in order to receive NÀÀ. I THE RICHARDSON CO., Manufacturers of Radio Apparatus ERIE, PA. have an aerial sixty feet long, composed of four wires, separated a foot and a half (Continued on page 522) you benefit by ',motioning "Toe Electrical Experimenter" when writing to advertisers.

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER Szl

TURNEY VARIO VARIABLE THE NEW TURNEY HEAD SET CONDENSER With Adjustable Pressure Head Band. M U I L C S R T R E E R O V A A E L A S D N J E U I N S N S T DIMENSIONS 6 "a6 ":3" SHIPPING WEIGHT 2 LBS. I SCALE READINGS O T M Seale No.1.0 to .001 M.F. Seale No.4 -0 to .00012 M.F. PATENT APPLIED FOR Seale No. 2 -0 to .0005 " Scale No. 5 -0 to.00007 N I E Scale No. 3.0 Io .00025" Scale No. 6.0 to .000055 " Scale No. 7.0 to .000035 M.F. MAILING WEIGHT N E Price $7.50 ONN V T Price $Ó.O0 PEXTRAE E The new TURNEY VARIO VARIABLE CONDENSER is DESCRIPTION -3000 Ohms, positive friction adjustments ideal for EXTREME MEASUREMENTS where absolute ac- which stay put. Bakelite ear caps, German silver top band, curacy is demanded. It is incomparable for WAVE METERS lenient back check, consequent poles, and like all Turney appar- and Regenerative Ionized Gas and pure Electron Detector atus is extremely handsome in appearance. The adjustable circuits. The entire instrument (with the exception of the base pressure head band affords real comfort no matter how long you which isaof Bakelite) is engine turned and is made with the wear it. NOTICE-All Turney head sets will be provided with greatest care. Don't buy a Condenser until you have seen the the lenient back check that consists of a special woven canvas TURNEY VARIO VARIABLE. strap which fits the head perfectly. A circular containing full information will be furnished on request Third Avenue Eugene T. TurneTurney CompanyCom an , Inc., NEW ,;ORK CITY

I IIIIII1111IC71I11111111111111I I I IC711I I ; THE WIRELESS TELEPHONE Do you realize tliat a thoroughly practical Wireless Telephone simple enough to be used by anyone has been produced? A GREATER INVENTION THAN WIRELESS TELEGRAPHY You don't have to be an operator to use the new De Forest Radio Telephone Transmitter. Anyone can talk over it the same as over the wire telephone, and the speech is clear and distinct and free from all metallic noises. De Forest Telephone Wireless Transmitter

11111-11- LQGATIONS COST For yachts, house boats, barges, corn - For one complete station comprising mercial ships, tugs, lighters, power transmitter, receiving outfit, Motor transmission companies, railroads, Generator and all accessories, mining camps, logging operations, lumber camps, insular communication, $325.®® farm service and a thousand other We offer radio telephone sets to cover uses, where a practical, dependable from 1 to 150 miles, either transmit- telephone is a necessity. ting sets alone or complete stations

R ADVANTAGES { CLEAR II IITINCOTSSPEECH, NO SPEI CIAL OPERATOROREQU REDAB[LITY Enclose stamp for new bulletin F.16 on oscillion type Radio Telephones DE FOREST RADIO TELEPHONE & TIELIEGRAPH CO. 101 PARK AVENUE Makers of the Highest Grade Receiving Equipment in the World NEW YORK, N. Y. unnlnnuunununamnmuuuuuu1n111111111111111uu1talununlunnuummnunnnnu¢ nunuuuuummnunnnuuuuunlnnunulnunutluuuuununlu a3 You benefit by mentioning "The Electrical Experimenter" when writing to advertisers.

www.americanradiohistory.com 522 THE ELECTRICAL EXPERIMENTER November, 1916

QUESTION BOX. (Continued from page 520) apart. My aerial is about seventy -five feet high. "Preparedness" A. 2. The following instruments will be required: A 3,000 meter inductive coupler, loading coil, 2 variable condensers, fixed In War or Peace condenser, crystal or vacuum detector; if former we advise you to employ Radiocite for the crystal and a pair of 2,000 ohm tele- Use Bunnell Apparatus No. 8833 Dandy Loose Coupler $6.00 phone receivers. A. C. QUERIES. Best and most durable. Our Cata- (665.) A. Goldman, Richmond, Virginia, log 36E wants to know : Up - to - date dealers Q. 1. How can the frequency of an al- illustrates ternating current be calculated? have them in stock. and des - A. 1. The frequency in cycles per second cribes about equals one-half the number of field poles on the alternator, multiplied by the number 300 articles of revolutions per second of the rotor. of wireless Q. 2. How are two phase currents obtained? No. 8654 Dandy 21 Plate Variable apparatus Condenser $3.75 A. 2. One method is by the use of four as well as collecting rings connected with four points other appliances. Send 2c. stamp for it, to on a direct current commutator; one pair being connected to points directly under brushes of opposite polarity; the other pair J. H. Bunnell & Co.'s being connected to points midway between these. Another method is to couple the No. 8804 Jove Crystal Detector Holder Radio Dept. armature shafts of two similar alternator On Dark Porcelain Be.e . $1.25 armatures together so that the electro -mo- Bea_ . . 1.50 32 Park Place New York On Handsome Composition tive -force of one is a maximum at the same instant that the E.M.F. of the otker is at the zero. The more usual method for commercial work is to use a regular 2 -phase alternator, wound for the purpose and having either four or three slip rings. Q. 3. What prevents an enormous current from passing through the primary coil of a transformer and burning it out? A. 3. The small alternating current that passes through the primary coil magnetizes RADIO the iron core, first in one direction and then in the other. This rapid magnetization and demagnetization means that the number of RECEIVING magnetic lines of force threading through the iron core inside the coils is continually changing. Viewed from a slightly different standpoint, it means that lines of magnetic TELEPHONES force are continually crossing the coils, or Pronounced by experienced operators to be the most sensi- that the coils are continually being cut by tive phones on the market to -day the lines of force. The result is the same You Ret the faint signals when you use the genuine Holtzer -Cabot from either standpoint, the changing mag- phones. netizations of the iron core causing the generation of E.M.F. in the coils surround- You get the very essence of comfort too. They fit the head per- ing the iron. The E.M.F. thus induced in fectly and weigh complete only I0% ounces. the secondary coil causes a current to flow SATISFACTION GUARANTEED OR YOUR MONEY BACK in the secondary circuit. Likewise the E.M.F. similarly induced in the primary for Booklet 1687X Send coil tends to send current through the pri- T E mary circuit in opposition to the original current. Thus the E.M.F. induced in the HOLTZERCABOTELECTRICC° primary coil acts as a counter electro-mo- B O S T O N . M A S S. tive -force and opposing the impressed volt- 6161.65 60.STATE ST. 101 PARK AVENUE. 1104 UNION TRUST II1.rl0 circuit, thus holding CH ¡ C A 130 N E W YO R K BALTIMORE age on the primary back the primary current. ACTION OF WIRELESS WAVES. OUR B1G SUBSC121PTION OFFERS Ever since the extensive commercial em- S O N PAGES 541 AND 542 ployment of wireless telegraphy, there have E been many who believe that the powerful Hertzian waves seriously affect organic life. In fact, some have even suggested that laws or regulations should be enacted to protect Arnold Navy Model Loose Coupler organic life against wireless waves. With Acsto said teerhey: "Arnold, a view to determining the extent and na- have seen your Ad. in the magazine for ture of the radio waves' influence on or- Price $15.00 months and had I known the instrument Dr. C. Abel -Mus- was as good as it is and looked so much ganic life and climate, better than the Cut I would have bought grave recently asked several questions on one sooner. I am glad I came to town and the subject to be answered by a number of had a chance to take one in hand and see prominent scientists. The summary of their for myself." no Needless to say he bought one. answers was that wireless waves have Ialso carry the finest line of Switches. Switch influence on organic life, nor do they alter Points. Cabinets and Accessories on the climatic conditions, although it is true that market. certain electrical stresses are capable of ac- Send 2c stamp for Bulletin No. 3 celerating rainfalls. Please Note NEW ADDRESS 327 East 119th Street, New York Electric flat irons are rapidly replacing J. F. ARNOLD, hand and gas irons hi English tailor shops. You benefit by mentioning "The Electrical Experimenter" when writing to advertisers.

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 523 THE HOW AND WHY OF RADIO APPARATUS. (Continual front page 493) on reflection it will be evident that when the primary circuit is open the primary cur- BUILD YOUR OWN DETECTOR rent magnetic flux is collapsing and in doing so the flux lines are caused to cut the secondary turns in a direction opposite to We can furnish you with high -grade parts at bargain prices. See our that at make of the circuit. Figs. 2 and previous advertisements, or send for catalog -it's ready now -no postage 3 will make this quite clear, as the ex- needed. panding and contracting lines of force are clearly shown therein. Dealers and Jobbers -Write for our Profit -Making Proposition From this discussion, as well as from the illustration given in Fig. 4, it becomes evident that in the ordinary induction coil, in Equip Your Sets with I NDESTRUCTO Potentiometer Controls the medical coil for instance, a pulsating AudioTron Potentiometer and Rheostat knits are made of u special uniform direct current passing through the primary composition and are designed to give Silent, easy and close adjustment of battery potentials by a constant and gradual increase not possible with one cell variation. winding is transformed into an unsymmet- This results in maximum oensitivcness. The rical, alternating current in the secondary B battery unit is of 7000 ohms resistance, in- winding; the half waves of which are not suring long life to the batteries. Any lower resistance wastes your battery. TheAudioTron harmonious. In the spark coil, however, ladestrueto Filament Rheostat, having no where the secondary potential is sufficient wires to corrode, lasts a lifetime. Its ease of to create a disruptive spark, the direct cur- adjustment is also obig feature, an,I it adds rent passing in the primary is transformed to the appearance of your set. B Battery Potentiometer complete$1.00 into an unsymmetrical, alternating current Less Lever and Knob .50 in the secondary only, when the spark gap Filament Rheostat complete 1.50 is sufficiently short to allow the weaker, or Less Lever and Knob 1.00 inverse half wave B, of the current to jump B Battery Potentiometer Unit Lever and Knob .50 .Knob and Lever it. If the gap is too long for the B half wave to leap across it, then the secondary current is practically a undirectional one. Largest Line of Loose Couplers on the Market It is possible to test the polarity of the All Styles, 200 to 15,000 M. All Prices, $4.00 Up secondary terminals by means of pole test paper or also a standard, liquid polarity indicator may be utilized. If two pieces of Junior Commercial fine iron wire are connected to the second- Amateur Dead -Ending f/edroVic kúf Gncá Standard Ultra ih/er preren/er; Types Types Senti for catalog Send for catalog ruse AudioTron, Navy Type, Loose Coupler

!/llf/erJ i/f DGG ,/ire WATCH OUR NEXT ANNOUNCEMENT ON A sir ; SUPER -SENSITIVE DETECTOR ( i'iDio/or iimnwrre / core elf , cu/-out T 1 TERMS: Always Transportation Prepaid, Satisfaction Guaranteed, Cash dips from Key can .smf rf AUDIOTRON SALES CO., 315 Lick Building, San Francisco

Proper Connections for Small Spark Coil with Electrolytic Interrupter qn 110 -Volt Circuit. ary terminals of the spark coil, one of theist will become very hot and the other will remain cold; the cold one being the positive terminal of the coil. As shown by the oscillogram Fig 4, which is that for a small spark coil fitted with a vibrator shunt condenser, the duration of the primary current at the break of the interrupter is quite short. The duration of this portion of the primary current is kept as short as possible, and aided in so doing, to a large extent, by the condenser shunted across the vibrator. This condenser ab- sorbs the extra or self- induced current of the primary, which would otherwise unduly prolong the demagnetization of the iron core. The general wave form of the primary current, and sensibly also its po- BUILDING A WIRELESS OUTFIT? tential, is similar to that shown at Fig. 4. There's more satisfaction and a heap more When the interrupter closes the primary dun assembling your own outfit. circuit, the primary current rises slowly to a maximum and at the rupture at the in- The transformer's the most important item; terrupter, the primary current and potential you can build the most efficient amateur wire- fall quite rapidly to zero. The quicker the less transformer ever designed by using our un- break of the interrupter and the faster the mounted transformers. demagnetization of the iron core, the more Let us tell you how you can do part of the work pronounced the intensity or potential of the yourself and get this excellent transformer at secondary induced wave, A. This is shown a remarkably low cost. graphically, and in a striking manner, by the oscillogram. Write for Bulletin T207 and Prices. Small spark coils may be operated in the regular way from A.C. step -down trans- The Packard Electric Co. formers. Where 110 volts A.C. or D.C. is Warren Ohio available it is a good idea to operate the spark coil with an electrolytic interrupter;

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www.americanradiohistory.com 524 THE ELECTRICAL EXPERIMENTER November, 1916

P iinniamiwnnan nnaananaanaanioaaaaammaaaain,aaamnwmnnnuunaunaaai nnennenaaemninmimnammaaimma1aa11aia1aaaaio111ia1nm1nuunnomo,noai 111 n1 nl 11a11111n,1,1a,1,1m1,111n1111,1ae,1,1,e,1,1a11,1a,1,1n11,1nl1111111111111111111111111111.11111111.111 aaann,15 see Fig. 5. Small coils, such as the % or 1 inch variety, should not be hooked up direct to 110 volt circuits, but should have a suitable choke coil in series with the pri- EXPERIMENTERS! .4$ mary winding and the electrolytic interrupter. All such installations should, no Save money by buying a matter how small, be equipped with a kick- GOOD storage battery back preventer of approved form. It is FIRST. The ONE thing Marko required in all cases by the Fire Underwri- you can't afford to Storage ter's rules governing radio installations op- experiment with Batteries are erating on commercial light and power cir- is a storage especially adapt- cuits. battery. ed for operation of all kinds of spark coils, 6\T8 insuring a heavy and THE SPERRY 1,280,000,000 C.P. powerful spark. There is SEARCHLIGHT THROWS BEAM nothing superior Marko GUARANTEED OVER 50 MILES. Storage Batteries are AUDION USE (Continued front page 484) crank carrying a crown gear, which engages not experiments I t is a well -known fact among up -to- - 111101 a gear on the vertical shaft is used to ro- they have been date wireless engineers and experi- tate the carbon menters the Audion operates at by hand if necessary. that I on the mar- s higher efficiency when The positive feed is operated by thermo- ket for 10 controlled by a storage bat- static control of powerful solenoids through tery that gives constant voltage. the vertical shaft. The thermostat years. Marko Batteries are designed to is meet these conditions. mounted on the drum and so arranged that Guaranteed hlahest quality and lowest prices. 'when the positive carbon burns out of the Borne Popular Sixes. focal point the Type Volts Amp.B.R List Special price to of mirror the light from Capacity Price wireleas mutineers its crater is brought on 4C2 4 40 $ 7.00 84.20 to the ther- 6C2 6 40 10.00 6.00 mostat, causing feed of the positive carbon 6C4 6 60 12.00 7.20 6C8 6 80 16.00 9.60 'until the focal point is again reached. This MARK O' QUALITY automatic control of the positive carbon is PAUL M. MARKO, 1191 Bedford Ave., Brooklyn, N.Y. The Mark -o' Quality 'also supplemented by hand control. New York Depot -974 8th Ave.. New York City The feed of the negative carbon is controlled by a solenoid connected directly across t h e arc and moves the carbon in the proper direction as the voltage rises or falls. The automatic feed of the negative carbon is also supplemented by hand control. A striking solenoid moves the THE MOTOR OF A HUNDRED USES entire negative holder back the proper arc "National" Combination Universal Utility Motor length on striking of the arc. The entire negative carriage can be A Necessity for Home and Shop turned on the right to permit new negative Some of Its Uses carbons to be inserted; when so turned, Rotary Spark Gap -Grinding Pollshing- the grip on the carbon released Bumng- Running Sewing Machine- -Small is slightly, Lathe- Fan-Toys, etc. permitting a new carbon to be slipped in Not a Toy But a Sturdy easily. Motor The operation of the Sperry lamp is very Dependable steady and requires but very little Variable speed 2000 to 6000 It. P M. furnished attention to operate on any circuit AC. or IA'. after the simple adjustments for length of Our Special Price complete @ the arc, speed of rotation of the positive with CARBORUNDUM W carbon, and the feeding of the carbons have WHEEL, POLISHING Fully been made. positive BUFFER AND TWO Guaranteed The carbon is inserted ARBORS. Regular price$6.50 into the holder by slowly rotating it and pushing it forward at the same time. Build Your Own Rotary t;pk A rheostat is used in series with the arc, adjusted so as to get a voltage across the YOU WILL SAVE MONEY BY BUYING COMPLETE PARTS FROM US 'arc of about 75 volts. A very important advance in This Illustrated set Is the same as used on our this work "NATIONAL" HI -TONE GAP consisting of a has been in the manufacture in this country highly polished aluminum rotor mounted on a genuine hard rubber t'sk ready to be affixed to the of carbons suitable for such searchlight motor; two terminals also of polished aluminum arcs. Formerly the only source of supply equipped with hard rubber adjusting knobs and removable sparking points. High-class workmanship of carbons suitable for these results was used, its appearance is very attractive. Can be Germany, but after many months of re- used on spark coils or transformers up to I KW. 'search work it is now possible to manufac- 201 Set complete $4.50 202 Rotor complete 2.75 ture superior carbons for this purpose in 203 Stationary Terminal complete 1.00 this country. SEND FOR CIRCULAR Searchlights of 24, 30 and 60 -inch diam- National Electric Manufacturing Co. eter of the Sperry type are being built. In 2118 Mailers Bldg., Dept.10 Chicago, Ill. addition, the Sperry lamps are being installed in old searchlights replacing the old form of arc. UNIVERSAL ELECTRIC MOTORS EXPERIMENTAL CHEMISTRY. (Continued from page 502) Operating on A. C. or D. C.-110 to 130 volt placed on top of it, to prevent it from over- 1/16 to 1 /4H.P. turning.] [Note :-The Manganese Dioxide was THIS MOTOR 0 O used with the Potassium Chlorate as a catalytic agent. The properties of this corn - '`$/ 1/16 H. P. Complete pound were not changed, this substance be- SPEED 6,000 R. P. M. ing used to help the reaction along.] The in For spark gaps -grinding- polishing, etc. reaction which took place the preparation of oxygen from Potassium Chlor- Send Postage for Catalogue ate and Manganese Dioxide, was as fol- OMEGA ELECTRIC COMPANY lows: (A) 304 So. Dearborn St. Chicago, Ill. 2KCIO8 -- MnOs 2KC1 -I- Malls -1- 30z Tarrr:iér + aft = Tñi0 r + ñ%Ti + [oasaem }'outbenefit by mentioning "The Electrical Experimenter" when writing to advertisers.

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 525

Another method of writing this equation is as follows: (B) 2KCIO3 = 2KCl -[- 302 [Potassium a [Potassium [Oxygen] IGo right down into Chlorate) Chloride) It is shown by the equation (A) that the leIP0 otl° the great railroad Manganese Dioxide was not altered by the yards and study the reaction. latest style of locomotives, ACTION 01? BURNING WOOD IN OXYGEN. cars and semaphores. Then Experiment No. 17- I pattern Lionel Electric Take one of the bottles of Oxygen, and Trains after them. Buy while the glass plate is in position over the mouth, slide the plate slightly to one side of ust Like Lionel trains and you have the bottle, just enough to admit a small REAL TRAINS, only piece of wood, as round as a match. Light the Big smaller in size. this thin piece of wood, and while there is Trains still a glow on the tip [but no flame], thrust it into the bottle, and notice the result. `. You can buy Lionel trains from your dealer, Try this over two or three times. Cover complete or in single pieces, and think of this -there are so the bottle with a glass plate after burning many different kinds of locomotives, passenger cars, freight cars, the splint in it. The following experiment to test for the trolley cars, etc., that there is always something new when you product of wood burning in oxygen can be want a change. made. Experiment No. 18- CHRISTMAS MAN! Pour into the bottle about 10 or 15 cc., OH! YOU of Limewater [Calcium Hydroxide] ¡Ca Tell father Christmas will be a failure without a Lionel train. Then [OH]2], and close the mouth of the bottle big, free showing line of send for my catalog the complete with either a cork, or the palm your with over a hundred pictures. Mark what you want, give it to hand, then shake the contents, and pour father and urge him to order from your Lionel dealer. He An into a test tube for examination. ACTION OF CHARCOAL BURNING J. LIONEL COWEN, Friend of the Boys IN OXYGEN. F Experiment No. 19- President THE LIONEL M F G. C O. "_ Obtain a small piece of charcoal [about 48L EAST 21st STREET NEW YORK CITY %x% inch] and place in a combustion spoon, or forceps, and hold in the flame of the Bunsen burner, until it has a bright glow. Then thrust it into the Oxygen [a different bottle than used in Experiment No. 17 or 18] in the same manner as Ex- periment No. 17. Notice what action has L/0 fi ELEC PIC taken place. ACTION OF MAGNESIUM WITH OXYGEN. Experiment No. 20- set DENDABLE Take another bottle of Oxygen, and This Loose-Coupler An it on the work table ready for instant use P f 5.AYSf and withal iEPnexpensive Take Tuning to 2500 meter waves with suitable amateur aerial. Dimen- as soon as the magnesium is ignited. sions 14 inches long, 6 inches high 6 inches wide. Shipping weight, a piece of Magnesium Ribbon about 1 or 2 5 lbs. Fully described in bulletin No. 104. You will want our bulle- inches long, and hold tightly with a pair of tins on Iii -Tone Transmitter, Oscillation Transformer, Variable Static No. 30 -31, Shunt, Amplifying Receivers, Rotary Motor, etc. A postal card will forceps as shown in Fig. then bring all these free, but tell us the particular one you are most inter- ignite the end of the ribbon, and thrust it ested in just now. immediately in the jar of oxygen. Observe Radio Apparatus Co. of America, Parkway Building, Philadelphia the action which takes place. [Note: -The Magnesium Ribbon must be thrust into the jar as soon as it is lit, otherwise it will burn up before you have a chance to place it in the jar.] BURNING IRON IN OXYGEN. Experiment No. 21- In this experiment a large bottle is re- 1 you quired, and about inch of water in the bottom of the bottle to prevent it from breaking. Have a piece of stranded picture wire about 2 inches long, and hold it with a pair of forceps. Heat the wire to a red glow and dip it while hot, into some powdered Be the sulphur. As soon as the sulphur starts to burn, thrust it into a jar of oxygen in the same manner as in Experiment No. 17, and watch and record any action which takes place. If no change is observed, repeat the operation. BOSS [Note:-It is necessary to use different jars of oxygen, for all the experiments mentioned above. Do not try two or more experiments in the same bottle of oxygen.] Learn Electrical In the foregoing experiments we have Meter Engineering coupon burned certain substances in the gas Oxy- The Most Important Profession in the Electrical Industry / Gentlemen:- More Electrical gen. Let us compare the difference in the Meter Engineers are needed. We must train them since ours is theonly school Send me absolutely In the world teaching Electrical Meter Engineering. A j half million new Electric meters will he free full particulars burning of these substances both in Air and Installed this year. Think of the demand for trained men! We have more f now than we ran supply. You can Be the calls for trained men / of Meter Engineering. Oxygen. Roes -qualify for the Rig Job -right In your own home in a few short months. No previous experience necessary. Send the for In the case of the splint of wood, we information. coupon Free Name know that before it was burned in oxygen, EARN $1200 to $3000 A YEAR it liad Meter Engineers get Big Money. You / Address only a faint glow, almost ready to go velope. Write can qualify. You can draw the Fat Pay En- out. today. Get Into this interesting, fascinating, profitable profession After it was thrust in the oxygen it NOW while we are enjoying unparalleled prosperity. Send the coupon today, the man who fires --not the one who Be immediately burst into flame. is fired -Be the Be,,. Fart Wayne Fort Wayne Correspondence C rdence School In the case of charcoal, it was similar to School, Dept. 335 -C Fort Warne, end / 338 -C Fort Wayne, Ind. You benefit by mentioning "The Electrical Experimenter" when writing to advertisers.

www.americanradiohistory.com 5 26 THE ELECTRICAL EXPERIMENTER November, 1916

the burning of the splint, namely it burned rapidly in oxygen. In the case of Magnesium, it might have been hard to distinguish the difference between the glow in and out of the oxygen due to the brightness of the light. In the case of iron wire, we know that we could not burn it in air. But it burned readily when we plunged it into the oxygen. If we could burn iron in the air as readily as in oxygen, the result to all iron stoves, iron vessels, iron buildings, iron ships, etc., FLASHLIGHT is obvious. THE COMBINATION OF A SUBSTANCE WITH OXYGEN. From the experiments performed we X -RAY FLUOROSCOPES SERVICE 6x7 size with Astrale screen @8 gn know that when a piece of wood burns in complete as shown . . WW oxygen, the wood becomes charred, and a "A ST RA LE" X -RAY SCREENS black mass, with different properties, is left salts directly Long-lasting, brilliant in place of the original wood. In Experi- h a vy clodelulimak ncrng screen dust sdt te proof as well as mechanically strong. ment No. 18 we performed a test to find Do not use old style paper screens easily punc- white light when and out what the wood formed when burned in tured and which deteriorate in time. oxygen. Sample order will convince you. where you want it, Standard Sizes Complete Screens in Frame Wood, we know, is chiefly Carbon; then 253 *1.50 5,7 $5.00 8,10 $10.00 the reaction which took place between the without bother or dan- wood and oxygen was as follows: ROSENTHAL LABORATORIES, CAMDEN, N. J. c + O = CO2 ger-that's what you [Carbon] +[Oxygen] = [Carbon Dioxide] get when you buy a The product was carbon dioxide [CO,], nEptOÌt which proved its presence by the Limewater ; "MARVELECTRIC" Test. The reaction which took place be- KNAPPi EXPERIMENTAL tween the Carbon Dioxide and the Lime - ELECTRIC SHCInTI]S 1;18 LABORATORY water was as follows: A complete outfit for performing In- CO2 + Ca[OHl2 = CaCOs + H2O numerable experiments. Demonstrates 75 Franco Flashlight Magnetism, Solenoids, Resistance, Carbon [Limewater] = Calcium Motors, Dynamos, etc. Strong, dur- ioxidel +[Calcium Hydroxide] Carbonate)''" able, well -made, fascinating and Instructive. If The white precipitate which formed after you are interested in electric, you should have One. shaking with li,aewater, being Calcium Car- bonate [CaCO,I. Better flashlights simply In the case of Magnesium, the product can't be made. They were was Magnesium Oxide; the reaction being: awarded highest honors at kig + O = Mg0 [ Magnesium] +[Oxygen] = [Ma gnesium Oxide] the Panama -Pacific Expos- The iron was converted into Iron Tet- ition. Every one is defin- roxide, the reaction being: itely guaranteed to give re- 3Fe + 04 = FesO, [Iron] + [Oxygenl = [Iron Tetroxide] AT ALL LIVE DEALERS liable service always. See Thus we find that when a substance burns Inslston your dealer showing you the KNAPP line- in oxygen an OXIDE is formed, as shown KNAPP goods are best. If your dealer cannot supply get you, order direct. Send for FRED illustrated tala- that you a genuine by: iogue showing a complete line of Electrical Motors FRANCO FLASHLIGHT Wood = Carbon Dioxide (CO,]; and Novelties ranging In price from 10e to 510. Magnesium = Magnesium Oxide [Mg0]; with a Radio Iron = Iron Tetroxide [FesOa1; KNAPP ELECTRIC & NOVELTY CO. Battery-and Sulphur = Sulphur Dioxide [SO,]; 523 West 51st Street, N. Y. City see for yourself how helpful Phosphorus - Phosphorus Pentoxide [P2O,l; Zinc = Zinc Oxide [7.nO]; they are. Made in many CHEMICAL DEFINITIONS. styles, selling at reasonable Catalysis- Catalysis is a chemical action Detectagraph prices. Send for illustrated by which a substance exerts a chemical effect, and which undergoes no permanent $12 booklet. change itself. The Manganese Dioxide as used together with Potassium Chlorate in the preparation of oxygen, is known as a INTERSTATE ELECTRIC CATALYTIC AGENT, or CATALIZER; and the process as CATALYSIS. NOVELTY COMPANY Combustion-Combustion is a chemical light and heat. 104 S. 4th St., BROOKLYN, action accompanied by N.Y. Decompose -To break up into simpler Ir Chicago : San Francisco : Toronto parts. Our famous Micmpho. Detectagraph is now offered at as extremely _price.pp This detenting instrument of marveloussensitivitr ea nae process of nswd fog Transmitter Decomposition-The act or Outfit of Case and connector. 26-ít. Black breaking a into its constituent l',org RecyiReceiver, Headband,uncesand ce and Battery.512.00 The note - compound only two ounces. Price completecompkte ElY.ap for a limited nam- ber only parts or elements. MICR OPSfO- DETECTOR COMPANY Equation-A Chemical Equation repre- Gaston J7ofs,eonnault, P,re. 110-121 Naassu St.. N. Y. C. sents symbolically a chemical reaction, the Makers of Detecting Apparatus from 112.00 to $250.w Make Your Own Electric Light! symbols of the new substances formed by set up-to -date in noose Wm- the reaction being placed on the right hand, Inn t ands TIRE. Mew We can furnish you with D. C. Generators LABOR using while the symbols of the reacting substances Electr>< GémON AWeby Ìiawwlwiri ...eveer the and Motors from 80 watts to 1 K. W. are placed on the left hand. In a chemical latest ,nnnms and used house siciag-- eelectriciansri srfor an connection ALARMS as used by first class nor Also finished parts for same. Free instruc- equation the number of atoms of each ele- . BURGLARABLIGH a, ANNUNCIATORS n'me LAMB ELECTRIC cos u°arwc. T6eeeThese drawings are nothem the form of ment must be the same on each side of the 8wiringSan bk BO x on' for convenience in usingI g on the job. Send for tions to wind with every order. Trans- tm,hem, and if they don't make you more nano nt as a theman and save equation. hundred dines their cos! as a contractor, return them and money formers made to order. Send for wqill p retavded - --raa can't afford to be without them. Ow5 Dot.cAa catalog. An Oxide is a compound of oxygen with pot paid. ALL AT FACTORY PRICES another element. PATENT SPECIALTY COMPANY All kinds of Electric Repairing. Commu- Oxidation is the combination of oxygen 462 Sanchez Street San Francisco, Cal. with a substance. tators refilled a specialty. Slow Oxidation is the combination of ENTERTAIN YOUR FRIENDS oxygen with a substance without noticeable Send 10 cents for Two Standard Puzzles, and receive BERGMANN MOTOR WORKS light and heat. The rusting of iron repre- FREE Two Card Tricks, Two Coln Tricks, Two Joke Nov- elties, complete with apparatus and catalogues. 442.446 Niagara Street Buffalo, N. Y. sents Slow Oxidation. CHICAGO PUZZLE WORKS (Continued on page 528) 5310 Rev radon St. Room 117 Chicago, IH. You benefit b nentioning 1eThe Electrical Experimenter" when writing to advertisers

www.americanradiohistory.com Nm'enlhcr, 1916 THE ELECTRICAL EXPERIMENTER 527

Wireless Apparatus of Known Quality MESCO Short Wave Regenerative Receiver Recommended for relay work on Will increase receiving range of any wave lengths of 180 to 950 meters. It station over 100 times. is possible to receive wave lengths up Complete in every detail and ready to 1,000 meters with reduced amplifi- for operation when connected to an cation. aerial ground audion detector and tel- The circuit is the Armstrong regen- ephone receivers. erative with constants accurately A blue print of connections with calculated for the wave lengths when detailed instructions for setting up and employed in conjunction with audion operating this receiver is supplied with detectors. each instrument. Oak cabinet. Will receive undamped and damped The metal parts are of brass, nickel waves. No. 8.167 -MESCO Short Wave Regenerative polished. Receiver Price $32.50

Intensifying Transformer Variable Condenser Universal Detector Stand Can be used with any crystal detector in connection Capacity .001 M. F. a thoroughly reliable and scien- Remains permanently in adjustment. One of the with Audion. Signals can be intensified 10 to 25 times. tifically made instrument. most simple and effective Detector Stands made. No. 224 Price $12.00 No. 294 Price $4.00 No. 248 Price $3.00

Wireless Key The last word in efficient wireless key construction. No. 452 -N. P. Lever Price $1.98 Fixed Receiving Condenser Wireless Practice Set For stationary and portable outfits. Diam. 2 *' in. The most perfect set made. Equivalent to five Base removable and can be screwed to table. Large different sets. Supplied complete with Red Seal Dry capacity. Battery. No. 440 Price $0.83 No. 34^ Price $2.07 0-74) g`.-1a-

Wireless Spark Coil Telephone Receivers Rotary Spark Cap Very high grade. Can be used on 2000 miles. Ex- Will v nquestionably the best on the market today. Best ohms. increase the efficiency of any Transmitting coil to use on Dry Batteries as the consumption of tremely sensitive. 10J0 Station 20 to 30 per cent. Has very high clear note. current is very low. Made in 31-in. to 4 -in. The 3 -in. No. 4S) Price $6.00 Can be used on spark coils or transformers up to and 4 -in. supplied with separate primary condenser. 1 k.w. capacity. No. 495 -3-in Price $21.00 No. 222-6v Price $12.00 No. 496 -4 -in Price $34.80 No. 223 -IlOv. price $13.00 Send 10c. for New Wireless Manual A 9 The most complete book of its kind published. You cannot possibly afford not to have one. Contains 180 pages. Send for one NOW. YOU WILL GET YOUR 10 CENTS BACK ON AN ORDER FOR $1.00 Our Pocket Electrical Catalogue W28, 248 pages, mailed on request. This catalogue contains practically everything in general use in the electrical line and is in fact a small pocket encyclopedia of electrical goods information.

17 Park Place - - New York 1 106 Pine Street - St. Louis 114 S. 5th Avenue - Chicago MANHATTAN ELECTRICAL SUPPLY CO s 604 Mission St:, San Francisco

You benefit by mentioning "The Electrical Experimenter" when writing to advertisers.

www.americanradiohistory.com 528 THE ELECTRICAL EXPERIMENTER November, 1916

EXPERIMENTAL CHEMISTRY. (Continued front page 526) Reaction -A reaction is the chemical change or effect produced by bringing at You May Learn Theory, Code and Laws of Radio least two elements or compounds together, Communication in Our School or at Your Horn e whereby one or more new bodies are formed, which may consist either of a gas, fitting you for positions pay :ng good salaries with wonderful liquid, solid, or a mixture of these. chance to travel the world over. It's the most interesting profession known and the demand for skilled operatorsis increasing. Send stamp for catalog giving facts. Resident classes ACTIVITIES OF THE NEW open Oc.. 2nd. BRITAIN RADIO CLUB. NATIONAL RADIO SCHOOL, 14th & U Sts., N. W., Washington, D.C. (Continued front page 489) Offers Special Advantages and at sea. Many evenings when Arlington - á WASI-IINGTON for These Courses. or some other powerful station is sending, he can lay the receivers on the table, go to bed and still hear them sending. Then when he has had enough he can shunt the 'phones by means of a small switch on the bed. We Are Prepared to Teach You Wireless Mr. Bollerer obtains very good results Under Marconi Co.'s Chief with his set and hears many amateurs with -: Instructor in a radius of 500 miles. He hears a Consists of long distance wireless equipment of the very best commercial style provided K.W. set 250 miles away very plainly EQUIPMENT. Dy one of the large commercial companies with a 2 K. W. transmitter and receiving ap- and paratus, having a Trans-Oceanic range of 5.000 toiles. a g K.W. set 800 miles away from his sta- The entire eourse'sunder the direction of Mr. E. E. Bucher .InstructingengineerofMar- tion. Within 300 miles his signals can be PERSONNEL, conl Wireless Telegraph Company of America. Ills assistants stand equally high in the wireless field. heard very strongly. Many times he hears THE DEMAND FOR RADIO OPERATORS FAR EXCEEDS THE SUPPLY Colon, Panama, and Key West, Fla., work- Our licensed employment department assists out -of -town students to locate temporary employment while coming. He holds a radio license from the U.S. fortable accommodations are available in the new Association Building, location of which isi deal for students from Government Jersey, Lower New York, Long Island City and Brooklyn. Our folder E will prove of great interest and will give -call 1VH. He is desirous you much information regarding our school. of exchanging photographs of his set with MARC NEAR BROADWAY other amateurs. EASTERN DISTRICT Y. M. C.A. , , BAVE. N. Y. Mr. Mulvihill's set consists of the fol- 13 minutes from New York City Hall 18 Minutes from Hudson Terminals lowing: The receiving set comprises 1,800 meter loose coupler, Holtzer-Cabot receivers and two variable condensers set into the table. There are three detectors used, LEARN WIRELESS galena, Crystaloi and an Audion. A wave At the largest, best equipped and ONLY practical Radio school in New England. meter is employed to indicate the wave ENDORSED BY GOVERNMENT AND MARCONI OFFICIALS. Last year we length of the incoming messages. Two placed EVERY ONE of our graduates in good positions; operating in all parts of the world, and still are unable to fill the demand for them. Day and Evening classes now D.T.S.P. switches are used to switch on the in session. Send stamp for Heel Fall prospectus which contains detailed information. desired detector. TON INSTITUTE BOSTON' The receiving aerial measures 183 feet 899 SBOYL EASTERN RADIO long and 137 feet high, composed of 2 strands of phosphor bronze wire, spaced tt THERE'S MONEY IN /T " 10 feet apart. The sending aerial is 80 feet long and 137 feet high. HóME= LEARN TELEGRAPH Y-ÑÓM The sending instruments include a 1 -' K.W. transformer, a stationary gap and a MORSE AND WIRELESS_-_____ rotary gap having a speed of 9,000 R,P.M.; the disk is 6 inches in diameter with 12 plugs. There are also an oscillation trans- TEACI-I YOURSELF' former, a kick back preventer, a .001 mfd. condenser and two keys. in half the usual time, at trifling cost, with the All the wonderful Automatic Transmitter, THE OMNIGAAPN: operating switches are mounted Sends unlimited Morse or Continental messages, at on the switchboard in front of the set, any speed, just as an expert operator would. which makes it very easy for the operator I to handle it. Mr. Mulvihill has been _Ç a Adapted by U. S. Gov't. 4 styles. Catalogue tree. experimenting with a wireless telephone and --ITï"1I;, OMNICRAPH MFG. CO. has succeeded in working it up to a distance 39L Cortlandt St. New York of 5 miles. Signals can be heard from :'AA, NAR and NAX, with the 'phones 15 feet away. Under good conditions a dis-

E N. EC RI C'SOL is the pioneer and premier school of the "Learn by Doing" method. When you have completed this Course you shall be fully qualified to handle ALL branches of Electrical industry. The equipment of this School is unequalled and up-to-the- minute. No preparation needed to become a "learner" in this school. You can start to learn on any day of any week throughout the whole year.' Send for catalogue. New York Electrical School W 7 , New York Cit You benefit by mentioning "The Electrical Experimenter" when writing to advertisers.

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 529 tancc of 435 miles can be covered with the STUDY PRACTICAL ELECTRICITY sending transformer. His call is 1TI1. a Month The radio station owned by 50 The master- Through This Extension Course Mr. Wesley piece of watch Parker operates with an aerial 70 feet long, manufacture-adjust- Splendid op¡s,rtunity to master electrIcIty at home 40 feet high, composed of four ed to the second. positions, tem- through an extension couine of the School of Engineer- strands of perature ing of Milwaukee, the most thorough electrical school In No. 14 copper wire, spaced 2 feet apart. at factory intoyour choice America, with a iet'ord of 12 years of success lu teaching of the exoutsne new watch cases. Practical eletriity. hundreds of sucessfu' students. The lead -in is of No. 4 copper wire, run Not theoretical correspondence course, but Ideut.lcally to a 600 volt, 100 ampere, lightning switch. saine lessons -some lastrucn,rs-same attention -as at school. You cannot acquire the same proficiency In any From it there runs a No. 4 copper wire to 21 Jewel other way at hume. the ground proper. Without The receiving set is composed of a loose ONE YEAR'S TRAINING Cost mewAil ,.wo,non Burlington This masterful instruction puts you on the high rond to coupler (single slide) with loading coil, The great Burlington Watch sent on simple torment. good Pay at rate of $2.60 a month. You ge1 the watch at success ln the electrical profe.isloni -a wonderfully fixed condenser and galena detector, both jeAeler must nid -woefully short of trained men. Write for the same price even the wholesale pay. Fpayingoc folder "hlasier Electricity at 11ame. Tt explains made by the Win. J. Duck Co. Further Write Today for Free Watch Book how you can secure a year's course without cost and there is a pair of E. I. Co. 2,000 ohm See handsome color illustrations of all the newest prints out the many o pp1Ho,rtunitlex for earning big money 'phones. A designs in watches that you have to choose from. In the electrical field. Don't put It oft. write now. buzzer test circuit operated by Your name and address on a postcard is enough. SCHOOL OF PRACTICAL ELF.0 í RICITY a foot type switch on the floor is provided. Get this offer while it lasts. Write today. 605 Stroh Bldg. Milwaukee, Wis. Watch Co. Dept 7448 19th & Marshall BM. Chia The sending apparatus includes a 1 -inch Burlington Mesco spark coil, J. H. Bunnell key, Mur- dock spark -gap, and a home -made glass plate condenser, also a helix. Arlington is heard very loud without using the loading coil. The radio station of Mr. Robert Yuon is described below: A phosphor bronze four -wire aerial about fifty feet in length with a long lead -in is used. The ground is obtained through a connection to a water pipe. The receiving set comprises the following: one long wave loose coupler and a loading coil, by means of which he can tune up to 4,000 meters. There are two detectors, one crystal which is used on local stations, and one Audion which is used on the long distance work. For close tuning there is available a variable condenser; also DO YOU own a wireless station, either for sending or receiving? If you do, don't fail to join the greatest Wire- less Association in the country: THE RADIO LEAGUE OF AMERICA. if you believe in the preparedness of your country, if you wish to help Uncle Sam. If you wish to have your station officially recognized, join the LEAGUE. a national. non -money- making organization. Beautiful engraved and sealed certificate, FREE to all members. NO DUES OR FEES WHATSOEVER. Honorary Members: W. H. G. BUL- LARD, U. S. N.; PROF. REGINALD A. The Boss is Sizing You Up FESSENDEN; DR. LEE DE FOREST; DR. NICOLA TESLA. Whether you know it or not, he's on the lookout all the time for men he can promote. Send stamp for large 8 -page information booklet. He's ready and anxious to give you bigger work and bigger pay once you prove you can PO IT NOW. Address 233 Fulton St., N. Y. City handle it. But your chance for promotion depends entirely on yourself. If you're satisfied just to hang on where you are, rest assured that's as far as you'll a fixed condenser is shunted across the ever get. But if you want to get ahead, if you want to be somebody, to climb into a 'phones. position of responsibility and good money - The transmitting set is made up of the following: V2 K.W. transformer -coil which Get Ready -Your Chance Will Surely Come may be operated with an electrolytic in- Choose the position you want in the work you like best -then train for it. You can do terrupter or by vibrator on direct current, it in spare time in your own home without losing a day or a dollar from your present the latter being obtained by a rectifier, occupation -through the International Correspondence Schools. More than 100,000 men which changes A.C. to D.C. A rotary spark right now are putting themselves in line for promotion through the study of I. C. S. gap and a fixed gap are available but he Courses. Last year nearly 5,000 men reported advancement and increased earnings as finds that the rotary is the better of the the result of their L C. S. training. two. A glass plate condenser with twenty What the I. C. S. have done for r - - - -- reek OUT HEnC -ww rri. plates of glass and nineteen plates of very others they can surely do for you. I INTERNATIONAL CORRESPONDENCE SCHOOLS thin tin -foil is used. He obtains a very No matter where you live, If you can be reached BOX 5323, SCRANTON. PA. sharp wave and with conditions favorable by the mails, the I. C. S. will come to you. No for the poet. matter how humble or important present tiooti. or inthe ubject. befog which I mark XuaWy can easily transmit 35 your Posi- miles. Mr. Yuon tion, 1. C. S. training will help you go higher. No a ADVERTISING MAN ELECTRICAL ENGINEER chosen work may he, one Saleam oshlp Electric Lighting holds an operator's license and his call is matter what your some Commercial Law Electric Car Running IDG. of the 280 practical L C. S. home -study courses BUSINESS (Complete) Electric Wiring will just suit your needs. Certified Pablla Aeeoaaent Telegraph Expert A recent Club radio display included a Higher Accounting Prectical Telephony replica of Marconi's first set, which sent Choose Your Career -' Bookkeeper Railroader - Stenographer and Typist Mine Foreman OT Engles, the first message across the Atlantic; old Do you like Advertising f Many of the fore ~ Railway Accountant Metallurgist er Primness, most advertising managers in this country were WINDOW TRIMMER ARCHITECT and modem receivers; transformers, coils, I. C. 5. trained. Salesmanshipt Thousands of Show Card Writer Contractor and Builder detectors, sending keys and many other I. C. S. trained men are winning success in the Outdoor Sign Painter Architectural Dralsmae selling Accountings Commercial Lawf Common School Subject. Concrete Builder parts of apparatus constituting a complete game. Good English Structural Engineer wireless set. All over America accountants, bookkeepers, office Teacher Plumbing ad Heating managers, private secretaries, are reaping the re- Civil Service Sheet Metal Worker The Radio Club of New Britain was wards of training gained in I. C. 5. spare -time Railway Mall Clerk CHEMICAL ENGINEER founded two years ago and has been suc- study of these mhjects. Engineering f Archi- CIVIL ENGINEER Illuuretor tecture f Electricity t Hundreds of thousands of Surveying and Mapping Designer cessful ever since. To any person inter- MECHANICAL ENGINEER Teethe O se Sept. men bave climbed into big jobs in the technical Mechanical Draftsman AGRICULTURE Spaniels ested in the club's work the club extends an professions through 1. C. S. help. Machine Shop Practice Navigator Germas invitation to attend its meetings which are The has is sizing you up. If you want a big job Stationary Engineer Poultry Raising French held that cardes responsibility and good money, err ready Gas Engineer AUTOMOBILES itelten every Tuesday night. The fee for for it. There is an I. C. S. way to do it and all the membership is $0.25 a month and the initi- I. C. S. ask is the chance to show you what it is. Name ation fee $1.00. The way to find out is to mark and mail this Present canyon. Do it now. It will be the firs step upward. Occupation For particulars about the club's work and Street the requirements for membership address INTERNATIONAL CORRESPONDENCE SCHOOLS and No the Secretary, Radio Club of New Britain, Box 5323, Scraatoo, Pa. I city State 77 Linwood Street, New Britain, Conn. Blame of Course you want L not In Wolin.Wt, write it below. You benefit by mentioning "The Electrical Experimenter" when writing to advert:sera.

www.americanradiohistory.com 530 THE ELECTRICAL EXPERIMENTER November, 1916

IrkkNCOMETO DETROIT, STANDARD RADIO TERMS THE AUTOMOBIL DEFINED. CENTER AND cc gpSÍNES$, Detroit Approved by the Institute of Radio 11;11, trained men get Engineers. preference and get jobs quickly. No other Under this head we will define the most im- city or school offers such pos- portant radio terms each month. Save them and eibillttes. Factories endorse our pasting each in a book (properly indexed) you school, glad to get graduates, Y a radio dictionary. offer territory in which to sell cars will have handy and start garages. POCKET DIARY AND YEAR BOOK FOR 1916. 104. Signaling, Duplex: See Duplex Signaling. Earn $15 to $300 a Month 105. Sharpness of Tuning: The measure of the Edited by the Mechanical World. 429 Our equipment is complete. Studente build rate of diminution of current in trans- pages, 85 illustrations, cloth bound, 6 by cars from start to finish. Complete course fn Oki, Acetylene mitters and receivers with detuning of 4 inches. Price 25 Brazing. Welding and Cutting the circuit which is cents. Published by separate from regular course. All leading types of varied. Emmott and starting, lighting and ignition systems in operation. If dg is the decrement of the free Co Ltd., Manchester, Eng- 6 cyl. Lazier, 8 cyl. King used for road instruction. alternating current in the circuit and land, DETROIT IS PLACE TO LEARN d, the decrement of the exciting E. M. A large fund of valuable information has been 44AetoFactorles in Detroit. you get practical instructions. School F., then the sharpness of tuning is crowded into the pages of this pocketbook. There open all year. Enter classes anytime, any day. 3 closes da morning, afternoon 'Iv. arbitrarily defined as are one hundred and fifty pages of data on steam, tories ask fortra OETROIT oil and gas engines. Such details as indicators, ned mou constantly. RI HEM Or 111 A0101111fR7 di + da construction of boilers, steam calculations, valve START GARAGE - SELL CARS 106. Spark: An arc of short duration. laps and condensing plants are taken up. 107. Static: Disturbances caused by atmos- Separate chapters are devoted to structural iron ms á t enm i thlgutooucwithgrad- atse who intendt work, gear cutting, ball bearings, rope drives and t entering buainess.nave pheric charging of the antenna. ts with Eastern Investment the shrinkage of castings. Thirty pages are de- firm (worth million.) to back competent Note: When it is definitely known reliable. Michigan State Auto School that disturbances are due to atmospheric voted to tables commonly used by machinists and graduatesmgarageaodseltiugbudneas. charging of the antenna, the word Stat- designers. There is also a diary for keeping mechanical notes. A commendable volume, indeed, ACT QUICKLY Ñc;,eA.° c8tloa ic' shall be used. In general, disturb- with money back guarantee, NI FREE. ances shall be called "Strays." at such a low price, and one that will certainly Or better atilt, jump on a train hun- prove useful to anyone interested in such matters. dred, have donera a come to lathe Old 108. Strays: Electro- magnetic disturbances set Reliable School. We bave nobranches. astomt, CM. ¡O, up by distant discharges. MICHIGAN AST AUTdOkSCHOOL 109. Telegraphy, Radio: The art of sending A. c and receiving radiograms. ELECTRIC POCKET BOOK FOR 1916, edited by 671 Auto Bldg. 1148 Seldon Ave.. Detroit, Mich 110. Telephony, Radio: The art of sending and receiving radiophones. the Mechanical World, 240 pages, 130 il- 111. Train, Wave: The waves emitted which lustrations, cloth covers, 6 by 4 inches. correspond to a group of oscillations in Price 25 cents. Published by Emmott the transmitter. See also, Frequency, Get into this Group. and Co., Ltd., Manchester, England. interesting, profitable 112. Transformer: In present radio practice the It is impossible for such a small book to con- term audio fre- tain a complete compendium of electrical informa- and fascinating business should be restricted to tion, but this was not the intention of the pub- where the field is not crowded. quency transformers. See Frequency, lishers. The table and the data seem to have of used weekly. Audio. Thousands cards 113. Transmission, Diples: See Diplex Trans- been carefully selected to give the most important Department stores, clothiers, movie mission. data on the large number of subjects which it shows, etc., pay big prices -work done 114. Turfing: The process of securing the maxi- covers. quickly and casll y- pronta large - hundreds of lobs all mum indication by adjusting the time The first pages are devoted to definitions of around you. My students can more than pay for course period of a driven element. See Res- electrical units, followed by a discussion on the doing lobs in spare Stine while studying. Increase your care and installation of A.C. and D.C. motors salary, get a better lob or go Into business for yourself onance. and generators with calculations used in their 115. Tuning; Sharpness of: See Sharpness of circuits. Lighting and power circuits are rather Earn $18.00 to $45.00 a Week -Easily Tuning. as well as the controlling ap- 116. Vacuum Tube, Electrode: As ex- briefly covered, I will train you to till a bleb salaried lob. I person- Three paratus necessary. Data is also given on storage ally correct every lesson. 17 years' successful teaching. amples see Relays, Electron and Gas. and primary cells, electric lighting, measuring in- Thousands of successful graduates all over the world. 117. ['attain: Tube, Two Electrode: As ex- struments, earth connections, bell circuits, use of No town too emall, no lob too big for my graduates. amples see Rectifiers, Electron and Gas. Get my training -start now. electricity in mines, welding and elevators. The 118. (Naves, Electro- magnetic: A periodic elec- final pages are taken up by mathematical tables Big Money in Card, Sign and Bulletin Business tromagnetic disturbance progressive thru and a diary for the use of those who wish to space. notes. No other profession pays such firs -work comes to you in abun- 119. keen brief data dance-no job will stump you. psy students learn all. All the new- If 'ape Length (of an Electro-magnetic advertising matter on the first and last est, .wallet designs, (Nave): The distance in meters be- The run the pages (an abominable European custom in book- FREE Outfit ernwa how men, Guarantee tween two consecutive maxima, of the making) does not improve the book, but this seems how to keep records. in same sign, of the electric and magnetic Write 1101V for sapre- fact gives you a ram- to be characteristic of English publications. dal Bete You can competentI at craraáu- forces. training. i to nceliteraturecourses-- tes $85.00 120. Wave Length. Fundamental: See Funda- terms.. tettiman iala short _ monthly. ample lesson d tee deaainbe '0mëáeman N'ë mental Wave Length. Free Outfit or work a trained competent 121. In a THE ENGINEER IN WAR. By P. S. Bond. FREE-Don't low wages any longer -- Wave Length, Natural: loaded an- delay, tÌan Ìhe£ pÿjyaler leather, 187 pages act quickly. Get Started Now tenna (that is, with series inductance Flexible imitation or capacity) the natural wave length cor- (4x734 inches), illustrated. McGraw - Detroit School of Lettering, D.M. Detroit, Mich responds to the lowest free oscillation. 122. Wave Changer: See Changer, Wave. Hill Book Company, New York, N. Y. 123. Wave Meter: A radio frequency measuring Price, $1.50. instrument calibrated to read wave This book was written by an army officer and for large lengths. the material is reprinted, with revisions and addi- FR E E Send 124. Waves, Sustained: Waves radiated from a tions, from The Engineering Record. The aim of Catalogue of conductor in which an alternating cur- the book has reference to the training of the citi- rent flows. zen engineer to meet the military obligations of Practical Mechanical Books 125. Wave Train: See Train. Wave. citizenship. The duties of the military engineer are TESTS AND RATING explained at some length, while separate chapters STUDY 1001. Radio frequency generators should be rated are devoted to such topics as stream crossings, FOR HOME according to their capacity at continu- roads, fortifications, demolitions, map sketching and Best Books for Electn- ous load. The method of measuring out- sanitation. The work of the signal corps, which eians, Telephone Alen, put in operation is given in Sections brings in essentially electrical applications, is not Motion Picture Opera- 1011 and 1012 below. Unless otherwise mentioned, but the subjects treated on cover all AUTOMOBILE specified, a continuous load shall corres- the more Important duties of the military engineer tors, Engineers, Railroad STARTING pond to a locked key test. as outlined above. A number of excellent illustra- Men, Motormen, Drafts- LIGHTING 1002. Radio transmitting sets should be rated on tions help to make the text more comprehensive to men, Automobile MANLY the basis of their actual antenna input, the lay reader. It is a book worthy of attention Mechanicians, Plumbers, not including in antenna input the losses by all at this time and especially those skilled in Carpenters, Builders, in the antenna switch, and in antenna electrical and mechancial matters. Sign and Card Writers, loading inductances or series capacities. Bookkeepers a n d The radio transmitting set starts there- also fore at the first piece of electrical equip- Civil Service Applicants. ment definitely a part thereof, comprises ELECTRIC WIRING DIAGRAMS AND SWITCH- all further equipment, and includes the BOARDS. By Newton Harrison, with addi- F. J. DRAKE & CO. antenna switch and antenna loading inductances and series capacities (or any tions by Thomas Poppe. Second edition, Dept.6. 1006 Michigan Ave. other apparatus placed in the antenna revised and enlarged. Flexible imitation CHICAGO circuit which forms part of the trans- leather, 303 pages (4 /zx63/4 inches), 130 Sent Pentode or x1.00 mitting equipment; e. g., an antenna re- Norman Henley lay for break system). illustrations. The W. 1003. The over -all efficiency of a radio transmit- Pub. Co., New York, N. Y. Price, $1.50. This Complete Set of ting set shall be the quotient of the This volume is intended especially for those FREE Drawing Instruments actual power output measured in a stand- interested in the designing and constructing of $15.00 Draftsmen'. Complete Working outfit, absolutely free. ard antenna (either real or artificial) switchboards. Tables are given for the carrying They do not coat you a penny on this offer. Write for particulars. to the power input supplied to the first capacity of copper wires of various sizes, current $150.00 to $300.00 piece of electrical equipment which is required by carbon lamps (but not for Tungsten vy aunt definitely a part of the radio transmitter. lamps, strange to say), etc. The underlying prin- a Month ore ciples of the why and the wherefore of each com- to 8300 month and $,Ig Examples of the application of this rule books are the following: putation is explained briefly -too briefly it seems on drafting. Noo obligga- 1004. (a) A ship station. Direct current is sup- for many who will read this book. However, for . n ° Chlel Draftsman Dona, Iffy 3388 plied from the ship's mains to a motor those engaged in figuring out such problems in Engineers Eaulemt Co.,C Memo generator set, which furnishes alternat- their everyday work, this book will prove of service. ing current to the high tension trans- Considerable space is devoted to alternating cur- former of the radio set. The ratio of rent calculations, transformer connections for Learn Watchwork, Jewelrywork and power in the antenna to power sup- phase changing, circuits of various types of watt- A fine trade commandinga good sal - plied to the motor of the motor gen- meters, etc. It - would seem preferable to have Engraving. ary, and your services are always in erator set and to the auxiliary radio presented the A.C. line values for inductance and demand. Address HOROLOGICAL Department, equipment (e.g., blower motors, rotary capacitance in tabular form instead of in rather Bradley Institute, Peoria. Ill., for our latest catalog. gap motors) is the over -all efficiency. brief formulae. You benefit by mentioning "The Electrical Experimenter" when writing to advertisers.

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 531

R. S. & A. B. LACEY Established 1869 Members Bar United States Supreme Court and Supreme Court District of Columbia. C PATENT PRACTICE EXCLUSIVELY

Edited by H. GERNSBACK In this Department we publish such matter as is of interest to inventors and particularly to those who are in doubt as to certain Patent Phases. Regular inquiries addressed to "Patent Advice" cannot be answered by mail free of charge. Such inquiries are published here for the benefit of all readers. If the idea is thought to be of importance, we make it a rule not to divulge details, in order to protect the inventor as far as it is possible to do so. Should advice be desired by mail a nominal charge of $1.00 is made for each No matter haw much money you O UG H T toget for question. Sketches and descriptions must be clear and explicit. Only one side of your invention, it is notlikely to bring you a penny unless you know what you are about in selecangat- sheet should be written on. torneys. WELL-KNOW N patents worth trillions of PUSH BUTTON. several brass chambers. Other details are dollars, secured through us, made our reputation as (100) Wells Asbury, Clarkesville, Geor- also given and the apparatus is supposed to "The Attorneys Who Obtain gia, has submitted a very unique idea for be used by high schools, universities, etc. Patents that Protect" making an electrical push button for ring- (A) Without seeing sketches or more de- Abundant evidence, such as you can readily ing bells, etc., which generates its own curtailed description of the apparatus it is im- verify, will be submitted to show the unsurpassed rent. Our advice is asked whether or not possible to say whether a patent could be succors of our clients, and that pay There many The Patents We Obtain Are Not the Kind this could be patented, and if it would obtained or not. are so such Merely Said to be .Wanted," but the Kind to patent it. devices on the market to -day that we doubt that Manufacturers BUY (A) This idea is an excellent one, pro- whether one could be designed original No lower charges than ours are quoted by any other trustworthy attorneys; and we do not, by deceptive viding the button could be /manufactured enough on which a patent could be obtained. free otters. money -back schemes, or in any other way, cheap enough. There should be an im- use our terms as a bid or bait for pat:onage. Mere np- resentations, boasts, and promises, characterise much mense market for it, providing the button ELECTRIC AUTOMOBILE PLANT. fine patentllterature and advertising. but we challenge could be sold for $2.00 apiece or less. (105.) Claude Spitzer, Grottoes, Va., has a comparison of RESULTS. sent us a very elaborate drawing and de- Reliable book containing Information not obtainable Our advice is to get in touch with a pat- in any other publication and worth a possible fortune ent attorney at once. scription as well, of an electrical transmis- to YOU if you have Inventions to be patented, will be sion for automobiles. The device consists malledfree on request. Write. ELECTRIC BICYCLE. of a dynamo generator driven by a gas R. S. & A. B. LACEY, 99 Barrister Bldg., Washington, D.C. (101). Karl Lopsein, Germantown, Cal., engine, the generator in turn supplying has been figuring on making an electric current to two electric motors which drive bicycle and would like to have our advice the car. Our correspondent, who is certain as to its practicability and whether it will that a patent can be obtained on this de- work as described. The idea of the con- vice, wants our advice as to the practica- struction is to put a generator in a conve- bility of it and whether an article of this PATENTS nient place on a frame and run it by foot kind would be satisfactory from a manu- power which in turn supplies the current facturing viewpoint. YOU HAVE AN INVENTION finally to propel the (A) Electric IF for the motor, this transmissions on automo- can bicycle. biles are not new but the one of our corre- which you wish to patent you (A) While a device of this kind would spondent shows several distinct improve- write fully and freely to Munn & Co. undoubtedly work, there.certainly is no ad- ments, especially as far as the arrangement for advice in regard to the best way vantage whatsoever, as quite a good deal of the motors is concerned, which drive the of obtaining protection. Please send foot power is lost in the transmis- wheels. Several novel points of the are contained sketches or a model of your inven- sion of one form of power to another. in the invention and while we do not think We do not think the device practical at all. that a patent could be obtained on the in- tion, and a description of the device, vention as a whole, one or more patents explaining its operation. AUTOMATIC TRAIN STOP. might be obtained on several of the differ- (102.) Ina K. Robinson, South Haven, All communications are strictly conftdes- ent ideas. "Electric" automobiles seem to tial. Our vast practice, extending over a Kans., proposes to place a horizontal lever be coming into favor more and more, and period of seventy years, enables us in many on each side of the locomotive which there is a distinct advantage to have a cases to advise in regard to patentability would a few inches, the inner end without any expense to the client. Our Hand - extend gasoline engine drive a generator which in Book on Patents is sent free on request. This of each being connected to switches, such turn drives the automobile. This is not explains our methods. terms. etc., in regard switches to control a circuit so that when at once apparent to the layman on account to Patents, Trade Marks, Foreign Patents, the switch was closed the throttle would of the loss of the power. In automobiles, etc. be closed and the brakes applied. Several Ail patents secured through tie are described without however, a small loss of power is not con - lost to the patentee in the S. ien' ,:. A,nermn<. other points are mentioned in connection siiered much if the smooth working of the with this idea. car is taken into account and if the far (A) Devices of this sort are not very better control of electric driving is con- popular with the railroads, as they do not sidered. MUNN & CO. seem to favor extending levers, although a We would advise our correspondent to few railroads have adopted similar schemes. get in touch with a patent attorney. SOLICITORS OF PATENTS Unless an entirely new device were devised in such a scheme, we doubt if a patent NATURAL GAS FOR 699 WOOLWORTH BLDG., NEW YORK be could obtained. AUTOMOBILES. and 625 F STREET, WASHINGTON, D. C. (106.) St. Elmo Brumback, Missouri, in- BICYCLE CARRIER. forms us that he has been using natural gas (103.) Norman E. Himes, Norwich, r Conn., has an idea for a carrier for a bicycle which he thinks could be sold for Write for List of Patent Buyers who 25c at a good profit. It is to be made of PATENTS WANTED desire to purchase patents and What light sheet iron enameled and fastened un- To Invent with valuable list of Inventions Wanted. $1,000,000 in prises offered for in- der the seat. It is to be specially used to ventions. Send model or sketch for Free Opinion as to patentability. We have a carry books, parcels, etc. Special Department devoted to Electrical Inventions and are in a position to assist (A) While the device as described seems and advise inventors in this field in the development of their inventions. very satisfactory and while we think that a patent might be obtained on a device of MODERATE FEES --WE ASSIST INVENTORS TO SELL THEIR PATENTS this kind, we do not think that there is a Write To -Day for our Five Books sent free to any address. (See attached coupon:) very great market for such an article. COUPON! There are a good many such devices on .. the market already. i VICTOR J. EVANS & CO., Patent Attorneys i NEW YORK OFFICES: 189 -191 Broadway PHILADELPHIA OFFICES: 1419 Chestnut St. CHEMICAL APPARATUS. Main Offices: 779 9th Street, N. W., WASHINGTON, D. C. (104.) Dole A. Miller, Toledo, Ohio, 1 GENTLEMEN: ['lease send me FREE OF CHARGE your FIVE Books as per offer. has devised an apparatus designed to sep- ! NAME ADDRESS -= arate hydrogen and oxygen, consisting of - - You benefit by mentioning "The Electrical Experimenter" when writing to advertisers.

www.americanradiohistory.com 532 THE ELECTRICAL EXPERIMENTER November, 1916

in his stationary gasoline engine, and he i rv7' :: 2:r. x5ï'¿':v :1i;:8:' " ''ci MAGAZINE DONATES $10,000. wishes to know whether it would not be possible to compress the natural gas into a tank of suitable size in order to drive Our Readers May Profit by Generosity of Western ., _..,...... t1l11nI111IIIlIII II the automobile. Magazine Firm. (A) Anything is possible and there is no A well known Denver publishing house question that a scheme of this kind will ilüliilii!(( ; has appropriated $10,000 to be used solely work to a certain extent. The great ques- in a whirlwind circulation campaign. Their Ir19iIIIII tion, however, is, how far can an automo- offer is so liberal and the magazine so in- n1Ì11Íl Iil `if bile run on natural gas even if it should be teresting that everybody is eager to send in compressed into steel cylinders. The weight their names. of such cylinders would be quite high and The magazine referred to is 13 years old Small Holes Quick ! we doubt if 10 miles could be covered with and each month publishes stories of adven- such an apparatus. However, in certain ture, numerous engravings and sketches of You can drill small holes "as cities where natural gas costs practically quick as a wink" with western life, cowboy capers, descriptions of nothing, it might be possible to exploit an famous ranches, irrigation projects, land idea of this kind. But it would hardly be news, rich gold mines, etc., and tells how MILLERS FALLS practicable for cities, where natural gas and where to get homestea, s. It is the is unobtainable. As to patenting a de- oldest, largest and finest magazine i1í the AUTOMATIE POCKET BORER No.B vice of this kind, we doubt very much if west. Readers say it is worth $3, but in the patents would be worth much to the this surprising circulation campaign the One of the handiest little tools owner. that you can have. Length com- publishers are spending their money like pressed to fit your pocket, 4,74 water and our readers may subscribe three inches-extended 7% inches. STREET CAR INDICATOR. whole years for only 25 cents, six full Magazine handle contains 8 (107.) W. N. Thompson, New York years for 50 cents. It is the biggest honest drill points 1 -16 to 11 -16 inches City, has devised a street car indicator offer ever made. Remit in cash, postage and a screw driver bit. By a whereby the next street reached will auto- stamps or money order. Tell all your special device, each bit can be matically appear on a certain device in the friends. This offer may not appear again. released without disturbing the car without the necessity of its being Send today. Money back if not delighted. others. Chuck grips fast until watched by the conductor. He wishes to ;Mention the Electrical Experimenter and released. know whether a device of this kind is address Rocky Mountain Magazine Sta- tion 2, Denver, Colorado. (Adv.) See this handy tool at your dealers satisfactory and whether it can be patented. you'll take one away in your pocket.- (A) There are one or two such devices Mechanics' Handbook full of on the market and some of the European valuable Mechanical informa- cities have tried them. But, to our knowl- tion, never before printed, and edge, no great headway has been made. It PORCELAIN pocket catalog -free on request. is comparatively simple to manufacture a "THAT'S OUR BUSINESS" MILLERS FALLS CO. device of this kind, and if the car would even, Standard and Special Shapes, Regardless "Toolmaker to the Master Mechanic" always run perfectly all that would be necessary would be to affect a transmis- of How Difficult MILLERS FALLS, MASS. sion from the axle of the car to the device N. Y. Office: 28 Warren St. We Illustrate one hard shape we make. and theoretically this should work out A pair of rolls 7N" long and WI" in perfectly. Unfortunately, this never ap- diameter with 8 holes on ends and middle. pears to be the case in practice, for the They must be perfectly straight and we make them so. It's hard but not for us. simple reason that the car wheels going We can make your difficult, designs also. REGISTERED PATENT ATTORNEYS around curves experience more or less slip- Send us blue print for quotations. PATENTS AND .. -. TRADE MARKS page. Also, on a wet day the car wheels make a great many more revolutions than Union Electrical Porcelain Works they do on a dry day on account of slip- page also. Consequently, the indicator TRENTON, N.J. would indicate a certain street long before 252 Ouray Bldg. -- Washington D C. the street in question was actually reached, Book "Inventions -Patenting and Promoting' Frey is Improvements wanted-Send for free bulletins &advice and if the distance traveled by the car Experimental and Model Work long enough, the information conveyed to the passengers would be entirely wrong. ELECTRICAL INSTRUMENTS AND This is what inventors have not as yet FINE MACHINERY It is worth Inventions developed. Special Toole. Dia; worked out satisfactorily. Cutting, Etc. while tackling. Gear Manufacturers HENRY ZUHR are writing for patents procured through me. FREE: 72 -page guidebook. 32 -34 Frankfort Street New York City "Successful Patents "; "Stepping Stones'. teontainin,rbundreda AUTOMATIC SELF -STARTER. of inventions wanted, etc.); and "Patent Promotion," Relia how to sell your rights; chief causes of failure, etc.) Send for (108.) Robert Fisher, Arkansas, has them. Free manufacturing facilities. Advice free. submitted an elaborate sketch and drawing GROBET SWISS FILES RICHARO B. OWEN, 164 Owen Bldg., Washington, O. C. of an automobile self- starter which works Are the standard of excellence In a files, and have been for over 100 on the principle of coiling large powerful years. We send postpaid as an In- PATENTS ADVERTISED spring which is automatically wound by the troducer 48 Elea especially adapted Magazine if engine when it gains speed. The energy for too: makers and machinists on In Popular Mechanics FREE start the receipt of $7.00. This Is a chance to get a set of secured through our Credit System. Send of the spring would afterwards files you'll appreciate and we'll get future orders. invention. Free search. engine when required to do so. sketch of we MONTGOMERY & CO. PAGE BOOK FREE (A) This is a very doubtful idea and 100 Fulton Street New York City 100 a could be made 4287 WWASHINGTON, do not think that spring WATERS CO. D. C. which would work satisfactorily for any Reliable Supplies for length of time on a device of this kind. Of course very powerful springs could be WORKING MODELS -N but are fully described in our interesting, new illus- =1::::t,aaa: - constructed to start turning the motor, trated 50 -PAGE CATALOG, 5c. postpaid. t? we have our doubts as to whether the de- Write today fora copy. SPECIAL ORDERS whether in are promptly and carefully executed by our vice would be practicable and mechanical department. Submit us your draw- the end it would not cost more than the ings and specifications for quotations. present starting means. /DEAL AEROPLANE & SUPPLY CO 76 -82 W. B'dway, X.Y. , The Most Powerful Nipper Made "RED DEVIL" No. 542-6N In. MULTIPLEX TELEGRAPH One lb. pressure In handles pro. SYSTEM. $125(2 to $3ooe a Month duces20lbs. powerinjaw. Cuts (109.) Chase Hutchinson, Knoxville, Write at once. Most wonderful opportun- the toughest wires with least sketch and description ite for the am- strain. Made of drop - forged Tenn., sends us a bitious man. system. He wants Railroads need steel. Sample 85c. ToolB,okktFYee of a multiplex telegraph hundreds of SMITH & HEMENWAY CO., Inc. our advice on same. Signalmen -will pay Big Money. 307 Chambers St. New York C ty (A) Devices of this kind are not practic- Special Offer ' w ll teach yov he ace Herr If yov write st ncpe o bogfoomhaar.. able. We think the expense is too great to wrlto To:lay fur oar freecatalog sood rdTuaa warrant practical use in exploitation and DEPARTMENT } Ravens wódSIatltatownsonnvn8388 ton,CMUgo th ,' a also because harmonic relays are too costly. You benefit by mentioning "The Electrical Experimenter" when writing to advertisers.

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 533

WIRELESS AND AEROPLANES AID sparks an inch long were drawn from the EUROPEAN "GUN- SPOTTERS." water main at a distance of three hundred ( Continued from page feet from the laboratory. 469) Revolutionizing the One very interesting experiment con- a hill is a common occurrence on many of ducted by Dr. Tesla showed how it is pos- the battle fronts of Europe, and it is one methods of teach- sible to tune several coils to different fre- of the standard exercises proscribed for quencies with respect to the fundamental the artillerymen of the United States Army. frequency generated by the main exciting As aeroplane radio sets have been greatly ing electricity coil. A photograph showing this experi- improved since the start of the present Eu- ment is reproduced at Fig. 4. The large ropean war, it is now feasible for aero- coil on the right, discharging strongly, is planes to maintain reliable radiocommuni- tuned to the fundamental vibration which cation over distances of forty to fifty miles. is fifty thousand cycles per second; the two Some of these wireless sets operate on bat- larger vertical coils to twice that number; teries, but the majority of them arc de- the smaller coils, wound with white wire, signed to be excited from a small dynamo to four times that number and the re- driven by the aeroplane engine. Aeroplane maining small coils to higher harmonics. radio sets of American design are being The vibrations produced by the oscillator turned out which do not weigh above fif- were so intense that they affected percepti- teen to twenty pounds. Specially designed bly a small coil tuned to the twenty -sixth receiving sets are supplied for aviators, harmonic above the fundamental. combining a leather helmet with the sensi- The scientific world is keeping its eyes tive telephone receivers in -built to form an peeled for the next epochal movement integral part of the entire head -gear. The in the problem of transmitting energy via antenna on aeroplanes lias to be especially wireless. And the world expects Dr. well insulated and many freak arrange - Nikola Tesla to do this. ments of the aerial conductors are to be seen. A single wire depending downward UNCLE SAM'S NEW 40-MILE AN from an automatic take -up reel is exten- HOUR "ELECTRIC" BATTLE - sively favored. In other cases the antenna CRUISER. is spread over the length and breadth of (Continued front page 479) the machine, and suitably supported so as spray burners, as compared to the bulky to be clear of grounding on the metal parts Scotch boilers as installed on the Cunard of the aeroplane frame and engine. liner, the Lusitania. The Lusitania developed 70,000 H.P. maximum from her LIGHTNING MADE TO ORDER. power plant, with a resultant speed of (Continued from page 474) somewhat over 25 knots per hour. This volts and a frequency of one hundred thou- vessel measured 790 feet in length with a sand per second! The flame -like discharge 98 foot beam. measures sixty -five feet across. This ex- Not only have the technicians of Uncle periment was performed for the purpose of Sam's Naval Construction Board evolved how the nitrogen of the atmos- Radclife's Home Study Course in Practi- showing cal Electricity being founded on actual elec- something startling in the form of a won- phere could be made to combine with the trical work, is now gradually and surely derfully fast battle -cruiser, but they will oxygen. The large wire cage measured 20 taking the lead in popularity over all other electrical of the kind. carry something entirely new in heavy ord- feet in diameter and 30 feet in height. books nance. the actual coil which is excited We can show you. w íthoutryour spending This is not one cent, just why this is so -why you are The big gun armament of these battle - by the primary of the Tesla transformer, losing valuable time every day you go with- cruisers will comprise eight 16 inch, 45 is attuned to a but a separate helix which out this library. rifles of a new type but de- secondary of the in inter- caliber recently certain frequency of the No matter what subject you are by Navy. It is be This is apparent by noting ested, you want to grasp the principles of veloped the U.S. said to transformer. that subject as quickly as possible. Accu- the most powerfLI gun in the world, firing the large circular fence -like wall in the racy in knowledge is the first consideration rear, which measures 60 feet in diameter -and second comes speed. From the Homo a 2,400 pound shell with an initial velocity and which is wound full with heavy copper Study Course you gain only accurate infor- of 2,600 feet per second, or with an initial mation about actual work. and you gain it energy of 100,000 foot -tons. wire. speedily. There is no useless theory nor The primary is carefully imbedded in higher mathematics to hold you back. You Hence, when the officer in command regular go forward quickly, and learn in a short pe- presses an electric button that discharges the ground and connected with the riod, that which the author has spent years oscillating circuit, comprising high tension in finding out, and you pay a salvo from this mighty fighter of the oil condensers and the inductance incor- seas, there will be represented a force of porated in the primary of the Tesla trans- $6 FOR THE ENTIRE COURSE 800,000 foot tons, from the big gun battery former, also a spark discharger. In Month alone -not to mention the secondary bat- At $1 Per -inch all these experiments the primary of the The coupon below brings the three volumes, beau- tery of six and smaller caliber rifles, low transformer was excited with tifully and strongly bound for ten days' examl- which will line the gun decks of the 900 - tension nation. Send no money with order. Commence 300 kilowatts of electrical energy. paying Ii per month only after You have satisfied foot armored hull. Thus, the primary bat- striking experiment showing the yourself that master electricity with the tery of 16 -inch rifles will develop sufficient A very óÌ books.cn emission of an electrical discharge from 6 energy to lift 2,000,000 pounds, 800 feet into A row of the Important Subjects Covered:-VOL. l a large sphere is shown in Fig. 2. The -Leading Principles. Electrical Units. Conductors the air. These large caliber rifles can be ball has a surface of twenty square feet and insulators. Calculation of Resistance. Electri- made fire minute cal Circuits. Primary Battery Cells. Storage Bat- to once every and faster which represents a large reservoir of elec- tery Cells. Magnetism. Electromagnetic Induction. when necessary. They will have about 25 circular pan under- Direct-Current Generators. Alternating Currents. tricity. The inverted Alternating- Current Generators. VOL. II- Trans- degrees maximum elevation and a possible neath with sharp rim has an opening thru formers. Electric Measurements and Instruments. fighting range of approximately 30,000 - Switchboards. Switchboard Wiring and Operation. which the electricity can escape before fill Station Wiring. VOL. III- Direct -Current Motors. yards. ing the reservoir. The quantity of elec- Alternating- Current Motors. Motor -Generators, It has been by al- Dynamotors and Rotary Converters. Incandescent declared naval experts tricity liberated is so enormous that, Lamps. Arc Lamps. Substations. Management that so remarkable is this new 16 -inch gun, though most of it escapes thru the rim of of Electrical Stations. favorable ball of that under conditions it would the pan or opening provided, the be possible to plant successive salvos on an the reservoir is nevertheless alternately - -- -Free Examination - -- enemy to overflowing, as is ship with accuracy, at a range of emptied and filled MOGRAW -HILL BOOK COMPANY, Inc., 25,000 yards. evident from the discharge escaping on 239 W.39th St., NEW YORK Home Study The most important functions cared for the top of the ball. Coursein ¡rat beat Electricity, three volumees. $6. I an alter- the satisfactory In by electricity on the modern battle- cruiser The coil shown in Fig. 3 creates ten da s, andithe atthefrt SI perfäonth, native movement of electricity from the books aro not wanted 1 will write you for shipping directions. or dreadnought of the class above de- earth into a large reservoir and back, at the scribed are partly shown in the accompany- rate of one hundred thousand pulsations Signature ing illustration with each particular part per second.. The adjustments were such Your Address numbered, so that those interested can that the reservoir fills and bursts at each readily locate the most important general alternation just at the moment when the City and State features of this truly wonderful craft. electrical pressure reaches the maximum. Name of Employer The key numbers start with the anchor with a deafening hoist on the forward deck, just in front of The discharge escapes His Address noise, striking an unconnected coil twenty - the forward 16 -inch gun turret. We will two feet away, and creating such a disturb- Your Position E E. Nov. consider here simply a few of the more ance of electricity in the earth, that heavy interesting and vital features involved in You benefit by mentioning "The Electrical Experimenter" when writing to advertisers.

www.americanradiohistory.com 534 THE ELECTRICAL EXPERIMENTER November, 1916.

the control and operation of these new elec- $11LHOMANS' tric battle -cruisers. ~TED MEN! As already mentioned, the power plant FIRST PRINCIPLES will depend upon oil fuel instead of coal. n-75 TO$300 A large battery of water tube boilers, as MONTIi! OF ELECTRICITY shown in the drawing, will produce a high - pressure steam and is fed into Demand for capable By J. E. HOMANS this the tur- automobile and tractor men far exceeds the Author of A. It. C. of the Telephone" bines, which are directly connected to the supply. Our graduates secure good paying positions r ''Self-Propelled Vehicles,' etc. as Salesmen, Demonstrators, actory Testers, Gar- of electrical science, or as a electric generators. These, in turn, are age Managers, Drivers and Tiactor Experts. As either a primer electrically connected main handbook of fundamental principles that would to the distribu- $50 Course FREE even by an advanced worker, tion switch -board in the engine room. This Only six weeks required to train you in this great be appreciated switch -board contains necessary school. Mostcomplete instruction. Instructors this book is in a class by itself. the meas- all experts. and 6U Tractor and Lighting lneenttga BOUND IN CLOTH, FULLY ILLUSTRATED uring instruments such as voltmeters and Free. Write today for our big Free Book ammeters, also protection apparatus such and 350 Frs. Scholarship Certificate. In the same series at $1.00 by mail RAHE'S AUTOMOBILE TRAINING SCHOOL as circuit- breakers, etc. There are a num- Largest Training School HOMANS' AUTOMOBILE HANDBOOK utoo ber of auxiliary switchboards besides, the 512 E 11 M 51.. Nanny CIh, Mo. SULLY AND KLEINTEICH principle function of which is to serve as 375 FOURTH AVENUE NEW YORK CITY remote control boards for the circuits running between the conning tower or bridge, just back of the forward 16 -inch gun tur- E S ret, and the propelling and steering motors. Y.M.C.A.RADIO SCHOOL GTIONSj. ILLUSTRA The entire equipment, or, at least the Has positions open now for first grade com- T.C.S. propelling and steering functions inherent mercial operators. to it, may be controlled from either the Fall classes forming, opening in October. ELECTRICAL ENGINEERS bridge or the armored conning tower just Instruction by Chief Radio Inspector of HANDBOOK below bridge, United States and first grade operators. Equip- 5 the and in event of the sup- ment includes all standard transmitting and erstructure of the vessel being shot away receiving apparatus. Code practice given in battle, the boat is still immune because directly from auen, Honolulu, etc. ELECTRICITY! of a third pilot room, located several decks Good Pay. Pleasant Work. Travel. on just the book below the conning tower, in a well -pro- Enroll now. Booklet on request. HERE'SElectricity that you need tected position as shown in the illustration. ques- to answer your many Thus, the vast difference between this mod- A. RADIO tions-to solve your knotty ern, electrically propelled and steered ves- Y. M. C. SCHOOL problems. to teach you new kinks, to 145 East 86th St., New York, N. Y. be your memory for tables, rules, sel, and the older, steam -driven types, be- formulas and other Electrical and comes readily apparent, as in the older Mechanical facts that some people try fighting ships the officers heads -and fail. on the bridge or to carry in their in the conning tower, had to give the men With this "Little Giant" I. C. S. Elec. tricot Engineer's Handbook in your in the engine room the necessary orders by pocket, tool chest, on your work means of an cngin''e room telegraph, as it bench, drawing table or desk, an hour was called. In these new craft, thanks to or a day need not be lost digging Jensen Electric Company up" some forgotten rule, some unfamiliar fact the high efficiency and positive action in- you'll just turn to the very complete index and herent to control by electricity, those in get it 'in a jiffy." Just a few of the subjects command on the bridge, for instance, can treated are: handle Electricity and Magnetism; Electrical Symbols; the vessel directly by means of suit- Radio Apparatus Batteries; Circuits; Magnets; Direct and AI- able switches and tell -tale annunciators lo- ternating Currents; Dynamos and Motors; cated before them. Belts; Shafting; Electroplating; Electrical and Supplies Measurements; Meters; Arc and Incandes- The electric steering equipment is of in- cent Lamps; Mercury Arc Rectifiers; Trans terest on these new ships, the rudder be- formers; Insulation; Electric Cars; Single and Multiple -Unit Control; Transmission; Rail ing swung either to right or left by means Welding; Tables of Wires -Sizes, Capacities, of electric motors controlled from the etc., -Mathematical Rules, Formulas, Sym- 1949 Huron St., Chicago, 111. bols; Tables of Constants. Equivalents. Roots, bridge or conning tower. And the exact Powers, Reciprocals. Areas. Weights and position of the rudder at any instant is Measures; Chemistry; Properties of Metals; made manifest by means multi -seg- Aid, etc. of a Principles of Mechanics; First ment switch mounted on the rudder post, The Electrical Engineer's Handbook is one of 22 which controls a lamp 1. C. S. Handbooks covering 22 Technical, Scien- annunciator on the tific and Commercial subjects, all crowded with bridge. The swing of the rudder from value. They have the contents of a full -size book Don't Wear a Truss pocket-size ready to go with you right to left is divided into a number of condensed Into small divisions BROOKS' APPLIANCE, anywhere and be at your instant command. each corresponding to sev- the modern scientific They are substantially bound in cloth, red edges, eral degrees of the helm arc. Each di- goldleaf stamping, printed from new, clear, read- invention, the wonderful able type on good quality book paper. There is vision is indicated by a certain annunciator new discovery that relieves- an illustration at every point where a picture lamp, which lights up when the rudder lies rupture will be sent on trial. will help. Hundreds of thousands have been in that particular angle. No obnoxious springs or sold on a money -back guarantee of satisfaction. pads. Has automatic Air Suppose one of these fighting monsters Cushions. Binds and draws The regular price is $1.25. but fora LIMITED to be steaming lazily along at sea, when the broken parts together as TIME you can buy the ones you want, post- suddenly a radio message is received (in you would a broken limb. for only 50 cents. No salves. No lies. Dur- paid. delivery guaranteed. either one of the two radio operating rooms able, cheap. Sent on trial shown in the illustration). And further to prove it. Protected by You Ron No Risk! Money Back if Desired! U. S. Patents. Catalogue consider that the radio message is import- and measure blanks mailed International Correspondence Schools ant, stating, for example, that enemy war free. Send name and ad- Box 5324, Scranton, Pa. vessels are but a short distance away. dress today. HERE. _TEAR OUT - Then, the all- important question to the lay- G E. BROOKS, 203 State Street, Marshall, Mich.. INTERNATIONAL CORRESPONDENCE SCHOOLS man is -Just what does happen in order Boa 5324, SCRANTON, PA. to get the fighting ship into battle trim instantly? WIRELESS OPERATORS I enclose $ for which send me postpaid the WORLD Handbooks marked X, at 50e. each. I may return any or all The officers and lookouts on the bridge SEE THE and get my money back within ten days from receipt: Positions always open. Good Electrical Engineer's Advertiser's and at the mast -heads, begin to scan the sea salaries. Day andevening sessions. Telepb.and Teleg. Engineer's Business Man's with their telescopes for the first sight of Correspondence courses. Wireless Mechanic's Bookkeeper's apparatus for home use. Send Steam Engineer's Steno. a.d Correspondent's the enemy. As soon as the radio order for illustrated catalogue. Westinghouse Air Brake Salesman's - Civil Engineer's Window Trimmer's has been received by the officer in corn Phila. School of Wireless Teleg. Coal Miner's Cotton Textile Worker's mand, he transmits the necessary instruc- 10 Parkway Bldg., Philadelphia. Pa. Concrete Engineer's Farmer's Building Trades Poultryman's tions to his subordinate officers. One of Plumbers and Finer's Mariner's Chemist's Automobile these men, by simply pushing an electric button on the bridge of the ship, causes AGENTS $60 WEEKLY Robinson Folding Bath Tab. Sie Reiter. Name general alarm bells to sound throughout little, water. W ht uná. fo os tosma l. Street the vessel. The sailors, gunners, en- Fulll length bathe. farin`lÌ better than and No. entire day gineers and others may be lounging about ay made Writefore free tuboffer. B.tia.. cairn.. sua. Cent nano. Bldg. Tokio. Obis City State the ship, but the instant these electric gongs You benefit by mentioning "The Electrical Experimenter" when writing to advertisers.

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER

begin to sound, they proceed immediately to their assigned battle quarters. the gunners are at their proper places in a few seconds. The decks are cleared of all their railings and loose fittings, such as life rafts or boats, including the life boats and launches on the super- structure, in proximity to the smoke stacks. If the decks are covered with wood, this is removed and thrown overboard, as it was found, in the Spanish -American War, that more damage ensued from the flying splinters of wood hit by shells, than from any other cause. Some of the splinters even entered the gun turrets through the gun loop holes. Also, there is constant danger of a conflagration when wood is present, so the imperative order now -a -days is to immediately dispose of any wooden object by casting it overboard. The fighting monster is thus entirely sheathed in steel, and a clear way is made in all directions for the cannon -fire. The general alarm gongs keep ringing periodically every few seconds, and in but a few minutes' time after the enemy has been reported, the fighting craft is ready for action. If desired, the officers give the order to those in the boiler room to regulate the machinery, drafts, etc., so as to cause heavy black smoke to roll from the stacks. This move is often necessary when other ships are to be screened from the enemy temporarily, or even to help conceal the vessel herself. For battle trips, the radio operators move their headquarters down to the battle radio room, located on one of the lower, protected decks, as shown in the illustration. This room is specially built for this insignificant sum you can get the great 1916 edition of the Cyclopedia with sound -proof walls and a door that yES,of Applied Electricity. See it before you decide to buy. No matter what you cuts off all sound. Fresh air is pumped want to know about electricity -here it is at your fingers' tips. The great authYor- into the chamber by an electric blower, so it ics have written it in plain English -so that you can grasp it instantly. These books that very little sound of the cannon dis- mean more money for you -promotion -the position you have been dreaming about, charges can be heard. and all you need to do to get the entire seven volumes is to send us your name and address. Use them seven days at our expense before you decide if you want to buy. In the preparations for battle the electricians have been among the busiest men on board. One of their principal duties is to lower over the side of the hull the two All About Electricity! auxiliary aerials ; one on the port side and The 1916 edition of Cyclopedia of Applied Electricity contains 3,500 pages, 7x10 one on the star -board side. Thus, there in.; 3,000 illustrations, full-page plates, diagrams, etc.; hundreds of valuable tables and are three radio antenna in service, and the formulas; carefully cross -indexed for quick easy reference. Printed on special quality enemy has to shoot down the port and paper and bound in half red morocco, gold stamped. Seven volumes. The standard star -board aerials and also that between the of America-the information that is vital to you and to every man who is interested mast- heads, before radio communication in electricity. And it is yours -on a startling offer, is cut off entirely. There are also provided sensitive, electric microphones for the de- Don't send us Read These Subjects Elements of Electricity tection of approaching submarines or other I a penny. We Electrical Measurements- vessels, Shipped FREE will send the -Underwriters' Require- these instruments being placed, of ments-Theory. Calcula- course, below the water line. Submerged entire seven volumes prepaid right to your home, so that you tion. Design and Con- can see and examine them for yourself. Keep them seven struction of Generators torpedo tubes are also- ready for service, and Motors - DDynamo- both fore and aft. The gunners, full days. Then decide if you can get along without them. Electric Machinery- as well If you think you can, send them back. If you keep them, Lighting Machinery - as those in the torpedo rooms, wear tele- Power Transmission - phone receivers pay $2.00 after the seven days' trial -and then $2.00 a Electric Railways -Power on their heads, which are (50e week) has been paid. You Stations Switchboards connected up with fire month a until $19.80 are the and Switching- -Storage the control officer sole judge-you do not risk a penny. This offer is open to Batteries -Applied Elec- located on the bridge or in the conning tra-chemistry Electric everyone in the U. S. and Canada. Elevators- Electric- Weld- tower. ing and Heating -Wire The push of a button on the bridge and and Wireless Telegraphy. the ammunition room door whistles sound; Consulting Service FREE ! MM. iM Mi MI MI a short time after the doors close, a tell- A year's Consulting Membership (regular price $12.00) will tale lamp American Technical Society before the officer acquainting him given free if you send your order at once. i The advice of Y with the fact. an entire corps of electrical experts is yours -to help you . E 3388 Chicane, U.S.A. E 1 Please send me Cyclopedia As soon as the enemy comes within in your progress -for a whole year FR E. of Applied Electricity for seven range the fact is communicated over the days' free examination. If I telephone system connecting keep the books will send 52.00 the range find- within sere$ days and 52. 00 a er officers, located atop the shell -proof, month until $19.80 bas been paid basket masts, to the gunners below. As Send i h e Coupon when books and Consulting Member - soon as he has found See these books for yourself before you decide to buy. will be the range, which niriffy amend hold bOtherwiseubject to takes but a few seconds, the man at the Remember-don't send us a penny. Just fill out your order. range finder telephones the corresponding the coupon and mail it. Will send you the entire distance, as well as the wind velocity and seven volumes prepaid. Use them seven days- other then if you want to buy pay the special reduced price at Name necessary information to the gunners the rate of $2.00 a month. Send the coupon now. Your throughout the ship. ambition says- act -see for yourself. Everything goes like clock work, and al- ' Address though it takes several minutes to read AMERICAN TECHNICAL SOCIETY A.lhave h:3 óa K.i: :ár:rm s:Gti re ,kre:ri just these few lines, all of the operations Dept. E. 3388 CHICAGO, U.S.A. here cited and a hundred others take You benefit by menttaning "The Electrical Experimenter" wizen writing to advertisers.

www.americanradiohistory.com 536 THE ELECTRICAL EXPERIMENTER November, 1916

place with absolute precision in a few sec- ute. The heavier, 16 -inch rifles, of course, onds. cannot fire so fast and a special circuit con- IJEWEL3 If the enemy ship presents a suitable tar- trols the salvo buzzers in all the turrets. SantaTe$pecial' Hoímf get for a broad -side or salvo, the officer on Thus, the entire fighting ship is soon put The REAL Triumph of watch manutac the bridge so informs the gunners in all under the dominant control of the officers turfing-Write NOW for FREE watch boon, showing newest case designs in 4 the big -gun turrets. These can be swung in command on the forward bridge or in colors. Read the so-called secrets either to port or starboard for firing a the conning tower. They may run the of watch making. Read how you broad 6 -inch can save from one -third to one -half -side. The gunners at the and vessel ahead or astern. When they deem of your money. Buy "Direct" at smaller rifles on the gun decks amidship it the psychological moment for a broad- factory cost - cutting out the are notified when a full broad -side is to side, they have but to press a button, and wholesale Jeweler's profit. be fired. before they can count 10, there will be Buy the Best Railroad Watch Salvo firing can be controlled very ac- hurled forth from the brazen throats of the "Santa Fe Special" curately, when necessary, by telephone, and the mighty guns an avalanche of shot and the only watch that's "Guaranteed the guns are fired (electrically) by the in- shell representing over 2,000,000 foot -tons for Life," thin model, all sizes, adjusted to positions, dividual gunners, on what is termed in adjusted to isochronism, adjusted to temperature, ad- of energy -sufficient to blast any ordinary justed to the second. naval verbiage -the. salvo buzzer. war vessel clear out of the water. THIS WATCH FIRST It is usual for medium size guns, such as In the gun turrets, electricity is the all - SEE Sent Without One Penny Down the 6 -inch rifles, to be required to fire with- important factor, as it proceeds to go about EASYoAFMENTStoeuaaou. n'rytr iodas,. Four. in 5 seconds after the salvo buzzer sounds; duties a posta! briny, the FEGE match book. its in a noiseless and uncomplain- 5 SANTA FE WATCH COMPANY, Dept. N-29, Topeka, Kan. seconds being allowed for reloading. ing manner. The gunner behind the breech This makes an average of 6 shots per min- of the 16 inch -20 mile gun has but to push a button when this mighty steel cannon rapidly rises or falls, just as he desires. Pushing another button causes the turret to revolve and stop at any desired angle or fraction thereof. Electric motors revolve the turret by means of rack and pin- ion. The telephone receiver gives him telephonically the range and angle functions as obtained with the range -finding instruments located atop the observation masts, as well as from range- finders on other parts of the vessel. The electric firing buzzer gives him the signal for dis-. charging the gun. Loud- speaking telephones are used for all such communications in many instances, particularly for giving orders between the turret chamber and the ammunition rooms, several decks below. The whirr and buzz of electric motors is heard as they hustle the 16-inch shells tur- 4J ret -ward. And so, as we go over the ship from stem to stern, we find electricity per- BEACON ELECTRIC WORKS forming a thousand and one wonders here OF NATIONAL CARBON COMPANY -there --everywhere. 132 -138 KING STREET, NEW YORK In moments of lighter vein when the 11-17 S DESPLAINES STREET 156 SECOND STREET Jackies are taking life easy, you may see CHICAGO SAN FRANCISCO how electricity is used for all the domestic requirements on board ship, whether it is BUYA AND BE GUIDED RIGHT." for washing dishes or peeling potatoes in BEACON the kitchen, or turning a lathe in the machine shop. Again, perhaps we hear the whirr of a motor as it busily revolves one of the rotary clothes washers in the laundry. And so we come to know that it is electricity that ventilates, drives, illumin- HI-PO ates and steers this wonderful creation of the human brain -the greatest naval advance in a decade. Once we were content WATERPROOF DRY CELLS to read about 40 mile per hour motor- And Ready for Use boats, but here we are face to face with CONNECTED SETS a 900 -foot, honest -to- goodness, hell- raising Highest quality and absolutely protected against moisture, dampness, sea fighter that can dash down on the 100% standing in water. enemy with express train speed and lash fog and spray. Give service even when the devil out of him with broadsides of 16 ", armor- piercing shells. Even the Kais- Set of 4 cells (5 volts) zgr $1.60 er will have to rub his eyes and blink at Set of 6 cells (9 volts) Uncle Sam's latest "peace -inspiring" per- $2.40 suaders. Other sets in same HIPO proportion TESLA VS. MARCONI COMPANY. The answer of the Marconi Wireless The only guaranteed Telegraph Company to the suit of the Nik- and original water- ola Tesla Company for an alleged infringe- proof Dry Battery. ;AR00 ment of its patents, was filed recently in the GUARANTEED Federal District Court. The Marconi Com- Beware of Imitations. DRY BATTERY pany denied that Mr. Tesla was at any time If your dealer does not the original or first inventor of the alleged new and useful method of signaling set handleour goods, send forth in the complaint. The answer also us his name with your No. 6 Cells 35e. each denied that the patents issued on March remittance. 17 and April 14, 1903, were duly or law- fully granted to Mr. Tesla, because he had not complied in all respects with the con- HI -PO Waterproof Battery Company ditions and requirements of the patent laws. 1007 Atlantic Avenue, Brooklyn, New York The defendant company asks that the complaint be dismissed. You benefit by mentioning "The Electrical Experimenter" when writing to advertisers.

www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER i;7

JAMES CLERK MAXWELL. front page EXPERIMENTS (Continued 471) BY had taught in London only eight years PHILIP E. EDEtr.iPN when the state of his health became such as to force his retirement to his country es- "Get Your Own Idea!" tate in Scotland. Somewhat improved by "Stick to it and put all your heart and soul into it every day" his stay there, he became professor of experimental physics at Cambridge, in 1871. Such is the advice of Alexander G. Bell, inventor of Only eight years later he died at the age at 70 years to the young man of today. of forty- eight. the telephone, At the International Electrical Congress, Ideas conic from learning about new things -how held in Paris in 19(X), the memory of Max- others accomplished wonders. And now conies Philip E. Edelman well was honored in giving his name to the with a new book to help you get "your idea." unit of flux in a magnetic circuit -this unit You are already interested In science generally, else you would corresponding to the ampere in electrical not be reading this magazine. Stop wondering -learn how marvels are devised by human brains. Don't "just putter around.' Make your circuits. work and hobby count for something. In China, you know, it takes two men to dig a shovelful of dirt -one to push the spade in and one to pull it up with WHEN AMATEUR WIRELESS WAS rope. But in America, the land of scientific experiments, a single steam shovel YOUNG. does the work of a thousand Chinamen. Don't imitate the Chinamen. Don't waste your time in useless endeavors. Let Edelman's "Experiments" show you how before you try to go ahead. Don't be satisfied (Continued front tage 488) another minute withou getting this book. The edition is limited. Telegraph your order, if necessary, but scene of ye scribe's activities shifted to for your own sake do not fail to get your copy of the city of brotherly love, Philadelphia. Here, after his miscellaneous "junk" and other paraphernalia had been ensconced in one of the famous (or is it infamous ?) old boarding houses, that line Spruce Street, "EXPERIMENTS """ 11E50 many wild dreams presented themselves to By E. EDELMAN, Author of "Experimental Wireless Stations" his imagination. One of the most perti- PHILIP nent of these was, that no longer would the 256 pp., 34 chapters; pro- "If it be true that the value old shellacked, two by nothing receiving CONTENTS- fusely illustrated with COMMENTS- of a book, whether it deal with suffice. Nothing to it must go. tables, charts, half -tones and engravings. fiction or with science, lies in its power to evoke new cabinet -it Price $1.50 in cloth or $3.00 in leather prepaid. thoughts and figures in the reader's mind, then this is And it did, giving way to a most wonderful "The greatest how to make it' book." a valuable book. The spirit of optimism which per- and fearful receiving "set." To begin with, 1. Copies and Makeshifts. Simple vades it, together with its ability to awaken and stimu- Book Models, 2- the normally this was to be a real outfit; one of those Chemical Experiments. 3-Miscellaneous. Applica- late somnolent mind, should insure for it tions of Chemicals. 4- Catalytic Experiments. 5- a wide circulation among an appreciative circle." - affairs that caused even your friends to Deposition of Metals and Electroplating. 6-Electro- Elertrice( World, New York City. throw up their hands and exclaim in won- chemistry. 7- Electric Motors. 8- Electric Heating "A very attractive series of experiments, selected with 9 Arc - der "What's this for ?" and "What's that Devices and Experiments. -The Electric a view to making the student acquainted with modern Electrical Devices. for ?" and "Why do you have to use this ?" Welding and Talking. 10- Simple progress and the way in which it has found itself, are 12- Electrical Transformers, Induction Ccils and presented with plates, engravings and half -tones in ad utftnitunt, about an an Ozonator. wireless and so on, for half Applications, including 13- profusion."- Srsentifc American, New York City. hour. By this time, after having read a Telegraphy, Telephony and Control Apparatus. 14- were, Telegraphy and Picture Transmission. 15 -High "A remarkably interesting work. The work is one number of books on the subject, there Frequency Apparatus and .Experiments. 16 -Phos- which may prove the inspiration of some new Davy, of course, always some new ideas to be phorescence and Ultra -violet Light. 17- Experiments Edison or Darwin."-Electricity, London. added or incorporated in the outfit. These asith Graphite. 18- Radiography and X-rays. I9- Electrical A. C. and D. C. Experiments. 20- Static This book is a year ahead of any similar volume; in- ideas multiplied bewilderingly and threat- Electricity, Apparatus and' Experiments. 21 -Me- deed- regardless of price -there is no other book like ened to even scare the writer in their enor- chanical Devices and Physical.Experiments. 22-Ex- Edelman's "Experiments." "I t is in a class by itself," mity. Before long there were so many periments in Horticulture. 23 -Model and Applied says the American Journal of Science, New Haven. A Aeronautics. 24- Microscopes and Microscopic Pho- coupon is attic ad f =.r ).ur convemenc. . Circular wires, switches, chokes, jiggers, shunts and tography. 2$-Suggestidns for a Laboratory. Free. ohm, condensers hooked up to the 5000 Book 2. 26-Science and Invention. 27- Essential polarized relay and coherer, that it is really Processes in Experiments. 28-Fundamental and Ex- doubtful when a regular wireless wave of perimental Principles. 29-Preliminary Experimental Work. 30-How an Original Research is Conducted. respectable power did manage to enter the 3I -Radio Research. 32-Simple and Industrial aerial and ground terminal post on the Testing. 33-Commercial Experiments. 34 -The ORDER NOW handsome oak cabinet, whether it could find Tomorrows of Experimental Research. Index. its way through the maze of apparatus. Mr. P. E. Edelman, 1802 Hague Ave., St. Paul, Minn. up This "set" was finally, however, tuned Experimenter's Library $2.85 I enclose $1.50 for "Experiments" (or S2.85 for in good shape and gave excellent satisfac- consisting of "Experiments," complete in two parts, "Experimenter's Library") which you will send pre- tion. The two -inch spark coil was usefully and "Experimental wireless Stations," by P. E. paid absolutely guaranteed. employed in giving demonstrations with it Edelman. Gives full information every reader wants -chemical. electrical, wireless, mechanical, and two pieces of brass tubing about three invention, etc. Former price, $3.50. Prepaid this feet long, served as aerial and ground, as month, only $2.85. Name most of the tests were made only through Philip Edelman,I802 Hague Avenue, St. Paul, Minn. the wall between two rooms, or between the third floor and the first floor of the dwell- Address ing. An amusing, albeit not very pleasant ex- OUR TAINODN perience, comes to mind when on one oc- OFFERS casion there was a lecture to be given with SEE ON PAGESC541 542 this set at one of the local high- schools. At the last moment the glass coherer tube cracked and all the precious gold, silver and *********************** k* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** nickel filings flew pell -mell over the edge ç of the table and on the carpet. This was :oys ere Ils Your Laboratory! a hopeless case indeed, for the moment; CH EMCRAFT but, recollecting that not many blocks away A Complete Outfit of there was a scientific instrument company it Tr $2.00 CHEMICALS- (39 Chemical Reagents) who manufactured demonstration sets of s APPARATUS - (All Necessary Apparatus) * radio -telegraphic apparatus, a call was made it PAC çyW INSTRUCTIONS - )The 36 page themorae Book) * t^ +'r,v+? performing time on them at once. To be sure, they would yÿ- Each expe can be `repeated many be only too glad to sell a filling for a co- * ,p '+es' ,p ;-' Under the heading "Chemistry and Its Appli- herer. After we had sworn by all the Holy " t. .tam* § !k?t`. cation to the Industries" are many experiments * Saints that our set was really one of their s in which the products of our great chemical in- * * ls,ce ¡tesox1 ".r' ° dustriesare really manufactured on asmall scale,. * manufacture, and after waiting for about Everything is explained in a clear interestingw ay. * an hour for the arrival of the precious fil- * ®o ®® Chemcraft also contains 30 mysteriousexpen- ings of unknown origin, they came to hand, * (? meats in Chemical Magic. It's great fun to it t show these to your friends. .1 s- and f 0 With the bill nearly knocked off our hats. * \® this outfit all experiments now appearing in i a n * it n ® "Expo; For they $2.00 ® Chemistry" in the "Electrical Expert- only wanted for each filling and there were two fillings in the en- it - - If your dealer does not have Chemcraft we will * velope, which the clerk politely stated to be ìt T- _ _ - _ send yours direct. Price $2.00 postpaid. Send * the minimum order for them which they it -` " -?- today for descriptive literature. * would handle. . Dealers write at once THE PORTER CHEMICAL CO., Hagerstown, Md. * One more experience will be related and *** **4t *yp,***** r**. lyyr**yr>{ttcAe****>{ e**** ****>{ r***sr*>{yr*.K.tr>{r>at.tr>{r*** You benefit by mentioning "The,Electrical Experimenter" when writing to advertisers.

www.americanradiohistory.com 538 THE ELECTRICAL EXPERIMENTER November, 1916

one which will be quite familiar to every pened, and then some, in the ensuing month electrical experimenter who has lived away and a half during which the construction from home, cooped up in one of those pri- of the coil parts and particularly the sec- vate boudoirs de luxe for which the hon- ondary proceeded with all possible haste. ssons orable boarding house mistress has the cour- Patience is a virtue, to be sure, but it has These books tell of this wonderful age to demand anywhere from 3 to 5 cold si- a doubtful 30.e f spinal adjustment, and variable place in the vocab- 000ttico, yet bsoluutely true. moleons per week. In one of these almost 30eä,000 Americans pport Chira. ulary of the electrical experimenter. He no cured of lone. civilized habitats the writer had emnding hissasseab i. the audaci- sooner starts to build an apparatus when he Big Opportunity for Ambitious` ty to undertake the construction of a large begins to anxiously Men and Women. Resident and Home long for the final mo- StudyaCourses. targe demand fer rartition- spark coil. Every electrician knows what ment when s- 42.000 to 5:,000yea ly. small expense. everything will be ready to Easy payments. Wo fit y State Hoard that means. For, if it is to be a regular throw in the switch and "Thes. FREE! LibenElbert Huostal. s watch the results. Bgui.ook Tbo New Science." Mail postal, get coil, the secondary must absolutely be made The spark W tee books FR80. coil, which was to be an eight - Nationaltional School of Chiropractic in sections and of course the thinner the inch one, got along famously until it came O t il 421 S. Ash!- d rais.. CHICAGO better, as we all know. Everything hap- to winding the secondary pies, each of which consisted of several hundred turns of TABULATOR BAR ADJUSTMENT very fine silk PAPER MAPCItJGUIDE covered magnet wire run MARGINAL STOPS I want, through this advertlee- through a molten paraffin ment, to establish as friendly wax bath, as .e- PLATEN RELEASE PAPER RELEASE .4 business relations with you as they were wound on to the former. I possibly can. I want you to Luckily, it was during the winter VARIABLE SPACING realize also, that It Is my earnest months '1 l effort and intention to give You that this exciting indoor sport took place, full, honest value for every dol- and though the author worked diligently at lar that you spend with me. it, even This In the only way I can suc- to the extent of spending every ceed. The publisher of this evening and holiday on the job, it required magazine will vouch for my well over a month until the 115th pie (God square dealings during the four bless CARR years and more my advertising it) was finished. If You do not know RELEASE bas appeared. what trouble is, then you simply have to try RIBBON 5 t carrying i I am building up my business on out such an operation as this in the foundation of good value someone else's home, yes, even in STENCIL GORY and square dealings. am sav- a board- CeRRfACa2 I Ing thousands Of satisfied Gusto ing house. Paraffine wax is a very inno- mers RETURNAND thousands of donate by cent looking commodity when it is solidi- AUTOMATIC fied. But visible, writingstypewrite s-at allow a fair -sized quantity of this SPACER remarkably low prices. important substance to be molten over a SPACER stove in a closed room All my transactions are handled and watch the re- RIBBON RE VERSE throughout by personal corres- sults. Not onl; an uncomfortable amount pondence. I assure, you every of smoke is produced, but there is a rancid TABULATOR BAR courtesy and consideration In your dealings with me. Your odor emitted with an unholy decrement, order will have my prompt, care- which has a persistent affinity for all doors, ful, personal attention. I will cracks and be glad to do business with you, other openings. The reader may judge for himself of the howls and kicks made by the other occupants of the house aQs)nt while these scientific operations proceeded c6l6wv with all due haste. This haste was not altogether and totally due to the natural desire to see the final results of the spark coil, nor to the black looks and ungrateful remarks of those who passed the laboratory TYPEWRITER SENSATION door, but distinctly and very pertinently to the fact that nothing but a gas light was supposed to be used in this boudoir. Fi- Free TRIAL-Use as You Pay nances had to ae stretched in those days to the utmost limit in order to pay for the Send me only $2.50 a month until the low total price silk covered wire and other gadgets which of $48.80 is paid, and the machine is yours were to adorn this masterpiece. A gas stove bill could not be counte- This is absolutely the most generous typewriter offer ever made. Do not rent a machine when nanced for one moment; you can pay $2.50 a month and own one. Think of it- Buying a $100.00 machine for $48.80. hence there was Cash price $45.45. Never before has anything like this been attempted. always intense excitement whenever someone knocked at the door, for at that psy- Standard Model chological moment everything, including and not forgetting the Bunsen burner which Visible L. C. SMITH Number 2 heated the wax, had to be heaved post haste into the nearest bureau drawer or in- Perfect machines, Standard Size, Keyboard of Standard 'Universal Ar- to the trunk, and the key turned. And, rangement, writing 84 eharaeters -universally used in teaching the touch system. what was worse, we had to conjure up a The entire line of writing completely visible at all times, has the tabulator, the two- face which personified innocence s color ribbon, with automatic reverse, the backspacer, ball -bearing typebars, ball- bearing itself, H. A. SMITH\ carriage action, ball-bearing shift action, in fact every late style feature and modern opera - particularly when the caller who had so po- ting convenience. Comes to you with everything complete, tools, cover, operating book litely knocked Room 738 ` at the door happened to be and instructions, ribbon, practice paper -nothing extra to buy. You cannot imagine Her Royal 231 N.Fifth Ave. \ the perfection of this beautiful reconstructed typewriter until you have seen it. Highness-the Landlady, snif- 1 have sold several thousand of these perfect latest style Model No. 2 machines at this fing suspiciously over the land! CHICAGO, ILL . ti t h. bargain price and everyone of these thousands of satisfied customers had this beautiful Yes, those were the palmy days -but nev- s h i me tit strictly up-to-date machine on 5 days' free trial before deciding to buy it. I will send a free sell itself, you are er again. The wife wouldn't stand for it. Number 2 I,. C. Smith. \ it to you F.O.B. Chicago for five days' trial. It will but if F.O.B. Chicago, as de- \ not satisfied that this is the greatest typewriter you ever saw, you can return it at scribed in this advertise- my expense. you won't want to return it after you try it-you cannot equal ment. I villpayyou the \ this wonderful value anywhere. THE MARVELS OF MODERN $10.00 balance of the tt You SPECIAL 848.80 purchase Take No Risk -Put in Your Order Now PHYSICS. price at the rate of $2.50 t When the typewriter arrives deposit with the express agent $5.50 and take the (Continued front page 485) per month. The title to re- \ machine for five days' trial. if you are convinced that it is the best type - main in you until fully paid \ writer you ever saw, keep it and send me $2.50 a month until my bargain ted, and on the strength of this a wonderful for. It is understood that I price of $48.80 is paid. If you don't want it, return it to the express agent, station was built on Long Island. Every have five days in which to ex- ` receive your SS.S0 and return the machine to me. I will pay the return amine and try the typewriter. express charges. This machine is guaranteed )just as if you paid reader of scientific periodicals is familiar If I choose not to keep it, I will \ $100.00 for it. It is standard. Over one hundred thousand people own with its picture and history. At present it carefully repack it and return it '\ and use these typewriters and think them the best ever manufactured. is deserted, but Testa is still working upon to the express agent. It is under- \ The supply at this price is very limited, the price will probably stood that you give the standard \ be raised when my next advertisement appears, so don't delay. the subject. The problem, however, is as guarantee for one year. it Fill in the coupon today -mail to me-the typewriter will be yet unsolved. We will not say it is impos- . shipped promptly. There is no red tape. I employ no solicitors sible solution, \ -no collectors -no chattel mortgage. It is simply understood of for do we not have real s. that I retain title to the machine until the full $48.80 is paid. wireless transmission of power as an every- Name \ You cannot lose. It is the greatest typewriter oppor- day occurrence in the ordinary transform- t. t nity you will ever have. Do not send me one cent. Get the coupon in the mails today-sure. er? Though there is no metallic connection between the primary and secondary Address coils, yet there is an immense transfer of `t,. HARRY A. SMITH power at only a slight loss. Notice how \, 738 -231 N. Fifth Avenue Chicago near the ideal conditions are, however. The distance is negligibly small, and even the You benefit by mentioning "The Electrical Experimenter" when writing to advertisers.

www.americanradiohistory.com i November, 1916 THE ELECTRICAL EXPERIMENTER 539 medium itsclf is improved by the presence The wireless era dots not mean an era of a soft iron core. It is too common a fact where wires are taken down and thrown for us to consider it wonderful, and yet the on the scrap heap. We must not look for Oh, You Skinny! result is the same as that which has puzzled scientific miracles for nature follows nat- AndhyoudoTHIN ve to go throughlife with cheat that the tailorOw, you; with . of many scientific minds to reproduce or du- ural laws. It means an age where an ex- childish strength with legs you can hardly on. And what about that stomneh that plicate through any great distance. tra gift has been given to man, enabling flstandinchen every me you try a square mean As wireless telegraphy and telephony Aro you a der. sup- him to extend his influence beyond the Ian you expect Health and Strength In plement, rather than take the place of the sphere of base matter ; to annihilate dis- tabloid Inrm-- Ihrough pills, potions and other emplaned pllllef ordinary systems and as the transmission tance and gain control over the finer forces Ion can't do It; It can't be done. of power is the back -bone of commerce and The only way to be wet le to build up your of nature. of it -- through nature's methods- -not industry, it seems the wires are here to [This is the tenth paper series pre- by pampering the stomach. It Is notate that of a Is making you s failure; it'e that pw emaci- stay for a long time to come. However, we exclusively Electrical ated body of o, your half- sickne sows pared for "The Ex- plain In your[ face, and world love.healthy must not disrespect the possibility of just perinsenter" by Mr. Rusk. Ed.] ppee..,»l,. Sob.Awlthy --.beep --mint. That's . Uont Nlnk t o long: Bend e me In as revolutionary discoveries in the future stamina to cover mailing of my hook,hook rose," LICENCE IN PHYSICAL emu HEALTH as have occurred in the Fast, hard as they BARON MÜNCHHAUSEN'S NEW GIraÌ,en by the a r peat physical cullare ,n- are for us to even conceive of now. Why, SCIENTIFIC ADVENTURES. sfrw foytm the troekl. even wireless telegraphy would not have LIONEL STRONGFORT ap- (Continued from page 513) PHYSICAL CULTURE EXPERT proached the success It has, if the energy Water on Mars is very scarce. None Dept. l' lift Park Bldg., Newark, N. J. radiated directly by the Hertzian oscilla- must ever be lost by seepage into subter- tor had been depended upon. In the first ranean soils, to vanish forever as far as place the decrease of energy, as shown by the Martians are concerned. This has al- the above law, would have been so great ready happencd on the moon, where no as to have been discouraging; and secondly, water is to be found along its surface ex- the fact that radiation travels in straight cept in the interior, and here most of it lines would have made long distance com- is ice. munication impossible, owing to the curva- By guiding the waters in waterproof ture of the earth. Both of these theories canals, practically no loss is occasioned by were advanced early in the development of seepage. Even where the waters are fi- the subject, and when approached near at nally conducted to fertile grounds, here to hand were neither of them found as forbid- grow grain, vegetables, trees, etc., they are ding as they had seemed. It was shortly not allowed to seep into the sub -soil. The found that when the sending station was method of doing this is as simple as it is suitably grounded, that the waves actually efficient. By means of the purple disinte- follow the surface .of the earth, and the in- grating rays, the site to be used later for vention of sensitive detectors made the agricultural purposes is treated exactly as transmission of a large amount of energy is the canal proper. This site, connected unnecessary for signaling. Many such facts to the parent canal by narrow feeders, is as about wireless telegraphy are a mystery to deep as the former and is, of course, wa- the average person, and although the math- terproof. It is then filled in with fertile ematics of radiation were actually worked soil and is now ready to grow plants, trees, Big Money in Electricity out over sixty years ago by James Clerk vegetables, etc. Thus no water is ever lost. Maxwell and his co- workers, many of the I must also add that when the emana- The electrical industries offer wonderful exact physical actions which take place are tion ray has transformed the bed of the opportunities to boys with a liking for Elec- but little understood even by the brilliant new canal into its lava -like condition, this tricity. The salaries paid to trained men are scientists of the present day. Much more is crust becomes conductive to the Martian large, promotion comes rapidly and, best of known, however, than formerly. Ion currents; the rest is an insulator. all, the work is fascinating. The wireless wave follows the earth as a I have explained to you before, that the The discovery and development of new huge conductor, because when the oscilla- waters in the Martian Canals are made lines (such as wireless telegraphy and tele- tions occur in the aerial, shown in Fig. 3, weightless by nullifying the gravitational phony), from time to time, promise attractive the lines of force moving up and down the effect of the planet, by conducting an Ion and paying fields to those who wish to aerial with the oscillating charge, throw off current through the bed of the canal. specialize, The uill to do and Special Train- loops as shown, which are waves traveling The waters, now being weightless, are ing will bring success to you. partly in and partly above the earth. These easily pushed along by the rays coming The International Correspondence Schools travel off exactly like ripples on a pond, from the stationary towers which line the can help you to become an expert in electrical and also follow the curvature of the earth. canal, as reported some months ago.* work, no matter what branch you like best. They are much stronger than if radiated in While this explains much of the mys- Thousands of young men have already won is all directions. .It evident they are not tery, you probably are still puzzled, as are success through I. C. S. help. You can do as wireless as they might seem, for the all our scientists, why the Martian Canals as well as anybody, ifyou try. Everything is earth acts as a huge conductor. In early are so tremendously wide. You know that made so clear that you can learn in your experiments between Lynn, Mass., and several of the larger canals measuring 3,000 spare time, regardless of where you live or Schenectady, N.Y., communication was miles in length are from ten to twenty miles what your work. No books to buy. found impossible, due to the dry rock wide. Why such an extraordinary width? There's big money in Electricity. Get mountains intervening which acted as ef- Would it not be better to make the canals fective, non-conducting carriers. Not long after it by marking and mailing the Coupon very deep and but a few hundred feet today. Finding cut carts you nothing. afterward communication was established wide, thereby saving an immense area of between Clifden, Ireland, and Buenos Aires, land, which is none too plentiful on Mars? C w OUT HCAC S.A., a distance of six thousand miles, the Again the answer is simplicity itself, al- INTERNATIONAL CORRESPONDENCE SCHOOLS intervening water being a good conducting though none of your scientists ever guessed Box 5 3 2 5, SCRANTON, PA. medium. it. Our host explained it to us in Explain, without obligating me, how I can Quality for Wireless telegraphy and telephony are a few sec- I the position, or In the subject, before which I mark X, onds. The answer to the riddle is: Evap- ELECTRICAL ENGINEER CHEMICAL ENGINEER now of immeasurable commercial value, to oration. Electrician SALESMANSHIP say nothing of their importance from a Electric Wiring ADVERTISING MAN For on Mars there are no oceans, not Electric Lighting Window Trimmer purely scientific standpoint. It may even be even lakes if you except small Electric Car Running Show Card Writer said that we have been a the circular Heavy Electric Traction Outdoor Sign Painter approaching as ponds at the junction of several canals, or L; euial Draftsman RAILROADER limit the wire transmission of power for wherever canals cross Eleetrle Machine Dedgeer ILLUSTRATOR In 1890 each other. Telegraph Expert DESIGNER some years. a power line was es- Now then, if the canals were not Practical Telephony BOOKKEEPER tablished, thirteen miles long, at Portland, so wide, MECHANICAL ENGINEER Stenographer and Typit the water would not evaporate fast enough Mechanical Draftsman Cert. Pub. Accountant Oregon, which transmitted current at 4.000 into air, here n Machine Shop Practice Railway Accountant volts. In 1903, Mexico, the to form water vapor, the Gas Engineer Commercial Law in a line was built latter to be deposited finally at the CIVIL ENGINEER GOOD ENGLISH 104 miles long, to operate at 60,000 volts, two Surveying and Mapping Common School Subjects poles in form of snow and ice. MINE POKER'S OR ENIIR CIVIL SERVICE while in 1913 the Pacific Light & Power The great width is absolutely necessary in Metallurgist or Prnapeetor Railway Mail Clerk Company of Los Angeles, Cal., began oper- order to STATIONARY ENGINEER Tenths Overseer or Supt obtain the required evaporating surface. ARCHITECT AGRICULTURE Spanish ating a line 240 miles long at 150,000 volts. ArehlteelursI Draftsmen Navigator German So nicely has all been Raising French This latter means a comparatively small this adjusted that PRIM NO AND HEATING Poultry by the time the canals reach their furthest Sheet Metal Worker Automobiles Italian current and a small conductor acting more North South and more as a guide rather than a vehicle or extensions, they carry practically no water in their shallow beds. Name for the power. Has a limit been reached; It Present or will this record has been used up mainly for irrigation Occupatlor distance and voltage purposes and soon be eclipsed? It is a problem the en- the balance has evaporated, Street gineers will An explanation how the Martians move the and No and scientists try to solve in waters in their canals is found in a previous in- the near future. stallment, published in the December, 1915, issue. [ City State You benefit by mentioning "The Electrical Experimenter when writing to advertise,.s.

www.americanradiohistory.com 540 THE ELECTRICAL EXPERIMENTER

to be re -used next season and so on. HOW THE WIRELESS AMATEUR Thus have these intelligent people FARES IN NEW ZEALAND: A wrestled with a tremendously vital problem RECENT "VIOLET RAYS" and by their superior intelligence their COURT CASE. water supply seems secure for thousands Through the courtesy of one of our read- of years to come. ers of Wellington, New Zealand, we are But my chronometer tells me that the able to present some side -lights on the recording wire of the Radiotomatic Plant Amateur Radio operator's existence in that on the moon is almost full to capacity. I country, or rather his non -existence. The must break off till tomorrow. Good Bye, following brilliant excerpts from the court my boy. Professor Flitternix joins me in testimony of a recent "violation" of the my salute. Au revoir and once more good Radio Act in force in New Zealand, make night.. . highly humorous reading. The maximum (To be continued) penalty for violating the law by erecting an experimental or any form of radio sta- Electricity is now extensively used to tion is $2,500.00, sufficient to deter most harvest ice from rivers and ponds. The anyone from experimenting with either electric motors drive the ice harvesting wireless or the law. We read in "The Taking an Ozone treatment at home machinery, trim the cakes and elevate them Poverty Bay Herald" for July 4, 1916: to the ice houses. The hearing of the case in which Ercih Violet Rays are becoming more popular Mervyn Goffe (aged sixteen years) was every clay. The great benefits deriving charged with erecting a wireless plant without the consent of the Government, was from their application in common, acute proceeded with at the Police Court on July and chronic diseases have increased the third. Arising out of the saute matter Will- confidence of the professional and layman. iam Edward Goffe was charged that be- They are not dangerous nor do they tween January and June, 1916, he did aid his son in the committing of the above of- develop habits. fense They are used by thousands of doctors Mr. J. R. Kirk appeared for the defend- in their daily work. They are better than ants and entered a plea of guilty. any patent medicine and represent na- His Worship said he should require sonic evidence as to what the plant was capable ture's own helping hand to restore health, of doing. relieve pain, give strength. Our booklet, Detective McLeod said the case against "The Ray of Life," gives valuable infor- the buy was laid under section 164 of the mation, and is sent upon request free of Post and Telegraph Aet. The facts were that the lad, who was living with his par- charge. ents in upper Ormond Road, according to his own statement, startcd, about two years ago, to study wireless telegraphy. He erect- WESTERN COIL CO. ed an atrial as a preliminary, and about si.r 180 N. Dearborn Street Most Sensitive Transmitter in the United States months ago he completed the plant withl p Detection and tin Thune the necessary instruments, and he conu- CHICAGO, ILL. today e a nír w device. but han Ì eca ál nosh[ for man yearn dis roen known d eco ená.d by utenccd sending messages by dots and Wowed every alter of Police in the Unitedstates lita extreme asitivityr has been tested and endorsed by large n ber of but not send for more than vernm tdbcialaand nome of the leadmeáeteetiveathroueh- dashes, could ookt, Ire U plete i to York Cib. a small out- Does your friend subscribe to information write about a mile. Ile also erected in the saute yard about a chain away and the Electrical Experimenter? HOLLADAY DETECTO CO. SUFFOLK, VA. fit got a small boy to work the instrument, in order to ascertain if his machine would receive properly. No doubt his father knew the plant was there. There was a two and a half horse power benzine engine in the S=`T=O=P ! shed and the boy stated that he used the coils from this engine to get the motive power for the wireless, Mr. Carmine, the We hereby present the greatest bargain ever of- assistant supervisor of the local telegraph department, would explain the strength of fered in electrical literature. the instrument if it was properly fitted up. A complete volume of the Electrical Experi- fl'hen the plant was taken possession of it was dismantled. menter bound in rich, His Worship: Wizen was it dismantled? -Detective McLeod: On June seventeenth, dark green linen, stamped and the information was laid on the twen- with gold the ty-third. letters at Mr. Kirk said he could have brought evi- extraordinary low price of dence to show the foolishness of this plant as a wireless plant for transmitting or receiving, but he did not deem it necessary to do so. Now it was proposed to ask Mr. Carmine, who had not seen the machine working but only after it was dismantled, to speak as to its capabilities. He had ad- $1.25 Goffe and the boy to plead not vised Mr. guilty, when they would probably have es- Postage on 7 lbs. Is extra caped punishment. However, Mr. Gage desired to plead guilty to a technical breach. Mr. Kirk said he had an electrical expert Volume contains twelve numbers. 743 pages, 1,226 and who would complete articles. 1.742 illustrations, 227 questions and who saw the plant working say it was only a toy one. answers. His Worship said he would give Mr. Kirk A world of electrical information; the entire electrical an of calling evidence. Progress for one year; the greatest reference book on opportunity current "Wireless" -all at a price as low as the unbound Lewis James Carmine, assistant superin- copies would bring. Mind you. the book is durably bound with heavy covers. You will be proud tendent of the Gisborne Telegraph Depart- to have it in your library. We have only 300 copies. therefore be sure and order to-day. Ship- ment, said that in company with Detective ping weight 7 lbs. Add a sufficient amount for postage. McLeod, on June twenty -third last, he vis- Order today to avoid delay ited .bfr. Goffe's residence and inspected a small engine in the shed there. EXPERIMENTER PUBLISHING COMPANY, Inc. Witness was questioned as to the capa- 233 Fulton Street, New York, N. Y. city of the engine, but said he had not seen Book Department, it working.

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www.americanradiohistory.com November, 1916 THE ELECTRICAL EXPERIMENTER 541

Mr. Kirk objected, and also objected to mounted on the hotel roof, about 125 feet the witness assuming thc capacity. above the street level, a 24 -inch searchlight t Voice Thrower Witness said the engine aims sufficiently of 6(1 amps. capacity, operated on 110 volts. v Learn to throw your voice into A a trunk, under the bed, out in powerful to charge the accumulators lard the hall or anywhere. Lots of jn connection with the wireless plant. He MEXICAN WIRELESS PLANT IS " FUN fording the leacher, the saw the room where the outfit had been EN LARGED. Janitnr, Policeman, or Friends, and inspected the instruments. An addition to the wireless plant at Cha- Detective McLeod: Assuming they were pultepec, in Mexico City, giving that plant a The Ventrilo properly fitted up what -mould you say their radius of 300 kilometers, or 1,85(1 miles, and is a little instrument that fits into the mouth capacity would bc? -They would be capa- enabling communication between all the out of sight Boys of Mexico, has been com- or Gris canuse it. NEVER FAILS! ble of transmitting wireless signals. wireless plants A 32 page book on Ventriloquism His Worship: For what distance?- Well, pleted and placed in service, according to sent with the VENTRILO for 10Ct say they would reach any boat in a message received by Mexican Consul Royal Novelty Co. I should Dept. 38 SO. NORWALK, the bay. General T. R. Beltran. CONN. Detective McLeod: and about receiving? Witness: With the machine properly tuned and with the crystals it zerwdd be capable of picking up messages from the .- luckland and Wellington stations. Detective McLeod: The whole of the ficcessary instruments are here for transmitting or receiving[-Yes, with the exception of the crystals. (lt finally developed that the Amateur Since we published these two books last never had tried out the instruments; the January, over 6000 of each have been detector crystal having to be obtained from sold. If you are a wireless experimenter, England.) yon can ill afford to be without these two His Worship: The engine is not neces- latest authoritative works, published by sary for receiving, is it ?-No. knows So that the engine had no significance the one concern in America, that what -to- Fiend" really at all as far as receiving is concerned? - the "How make -it None whatever. wants. In these two hand books are This was a low resistance telegraph, I concentrated the most important, up-to- suppose?-I and not prepared to say; I did date wireless instruments and directions not measure it. how to make them. They are by far the Would you say it was a high: resistance most successful wireless books of the to say until machine? -I would not like I These season. Size of each book is 5x7 inches. tried it. two, 100 page books, each contain- book ing from 88 to 90 illustrations, are sold by substantially bound on a good Assuming it was a low resistance it would paper. The covers are in two colors. receiving long distane{ us regularly at 25c. a piece. not be capable of In connection with this most remarkable We really can not praise these works signals f-No. offer you ABSO- too highly. You will be delighted with (His Worship evidently is NOT an elec- can now get them LUTELY FREE, for a very limitcd'time. them. trician ! !-Ed.) His Worship: What distance do you mean? -Such as from Awanui or Auckland. EXPERIMENTER PUB. CO., 233 Fulton St., New York Mr. Kirk: You never saw the engine charge any accumulators?-No. Gentlemen: And you saw the house was fitted with On your absolute guarantee that your two big Wireless Handbooks are just as electric light?-Yes. . described by you, you may send me same FREE. All charges prepaid. You are to And the engine was used for providing ,end me these books at onee, and enter my name for a full year's subscription to the electricity for the house?-Yes. electrical Experimenter, 12 numbers, for which I enelose *51.50, the priee of the Electrical Questioned as to a buzzer, witness said Experimenter alone. such an instrument was not necessary in (If a 2 -year subscription is desired, enelose $2.S5.) connection with wircless telegraphy. It was used only for teaching thc boys wire- Jly name is less signals. There was no buzzer on the My address is plant in question. William John Sinclair, electrical engineer, (11) *Canada and Foreign Countries, 52.00 -2 years, S3.S5. manager for Turnbull and Jones, said he had inspected the plant in question. While a good deal of ingenuity [night have been used in the manufacture of the plant, wit- Become ness did not think it would work at all. His Worship: But the boy says it did, Doctor oaf Chiropracti.c a little at any rate. Witness: -He may have thought it did, Home but I don't think so. Witness explained the Learn at -Earn $3000 to $5000 a Year Here is your opportunity to qualify at home in your spare time to become a Doctor of nature of the instruments required for Chiropractic -to enter an uncrowded profession and make a big income. No wireless. To send a message one hundred matter where you live or what work you are nowdoing, if you are ambitious this plant, he said, would re- our Course in Chiropractic shows you how easy yuu can achieve independence. yards with it Some of our men and women graduates are actually making quire an aerial four hundred feet high. upwards of $10,000 a year in the practice ofthisfaecinatfng, The aerial in question was twenty feet high. profitable profession of Drugless Healing -the Science of (You don't say so? !!!-Ed.) The Judge, good old soul, in his recapitu- lation, highly commended such enterpris- Spinal Adjustment ing genius in the youth of the land, but to Never before has the demand been so great for competent Doctors of Chiropractic. Every thinking person knows that uphold the dignity of the law fined the "lad" the day of Drugless Healing is here, and that the masses of ten dollars and costs, and father fifty dole people everywhere are eagerly welcoming Chiropractic, the science of restoring health by means of spinal adjustment, as a natural, Lars and costs. And the innocent radio scientific substitute for the old outgrown system of "dosing" by in- set that was to be, never even whimpered ternal medicines. be Practicing one single dot ten feet. Must some- 20 Lessons Free to Convince You MtheMoneye l Adjustment thing like that which Senator Sorgum calls To show you quickly and convincingly what Chiropractic is we offer you 20Lessons of our Regular Course absolutely Free -also our big 64 -Page Book and Eight (s) Anatam!cal Charts beautifully lithographed in lifelike "Justice, shy boy, Justice!" colors that regularly sell for $16.00. And this farce comes from enlightened You can become a Doctor of Chiropractic In a surprisingly shorta time by our practical, easy simplified methodof home imatrix- New Zealand! tion. All needless theory is thrown aside -our course offers the Free Lessons Coupon shortest, most direct route toyyour degree of D. C.- Doctor of AMERICAN UNIVERSITY, Chiropractic. We give you, right in your own home duringyour' Dept 679 Manierre Building, SEARCHLIGHT ON HOTEL AN the training you Chicago spare time, just must have to succeed. Without cost or obligation send me by mail. EXCELLENT ADVERTISEMENT. NOW!Send for Our Big Wonderful Offer Prepaid,rrom For purposes of advertising and attract- $250 to $500 a Month for You bleFree Lessoá4.8f eBook ing the notice ap- That's what you can earn as an Expert Doctor of Chiropractic. of automobile travelers Special reduced rates nowt Mail Coupon or write today -Sure! Name proaching the city, the management of AMERICAN UNIVERSITY. Hotel Bancroft, Worcester, Mass., has had Dept 679 Manierre Building, Chicago. III. a,Address You benefit by mentioning "The Etectricat'Esperintenter" when writing to advertisers.

www.americanradiohistory.com 542 THE ELECTRICAL EXPERIMENTER November, 1916

HOUSEHOLD USES OF ELEC- TRICITY. Furnish illumination for the house. Heat water for shaving, or the bath. Percolate the breakfast coffee. Toast bread, Fry eggs or anything that will fry. Poach eggs, cook the cereal, or heat milk. Operate the washing machine and clothes Will you take a 20 lesson Wireless Course wringer. absolutely FREE -even postage charges Iron the clothes. Just as you prepaid? Run the vacuum cleaner. will receive Operate it, the sewing machine. cloth A course that tells you everythigng you can possibly warym[ Cool rooms with an bound, size know to electric fan. 7 x 10 ins., aininabouthe Pripet pies of Electricity. TheeSSecnond andbThird Knead the dough and bake the bread. 160 pages, 20 Lessons are devoted to magnetism, motors, generators and Grind, mix, chum, whip cream, make ice wiring. And then, by simple, easy stages this wonderful lessons, 350 Course illus., 30 ta- takes you into "Wireless .^ The mysteries of "Wire- cream, polish silver, etc. /PPS" are unfolded to you by the use of such simple lan - Heat a bles, with guage so skillfully used, that of necessity you must under- fireless cooker. every bit of in- stand everyword. Thesublect Is not treated super liclall y, Make the tea in a samovar. formation on however, for there is a whole lesson devoted to tbeTheory and Mathematics Cook food in a chafing dish. - Wireless y o u of this epoch marking subject To lend charm to the Course. tilelast Lesson (No. 20)1s devoted Ignite cigars. can possibly to a history of Wireless and the men who developed it want, besides The wireless course Positively cannot be bought, but will Keep hot the heating pad (used in place of valuable -in- be Bent absolutely free with a full year's subscription hot formation on (12 numbers) to the Electrical Experimenter at $1.50. water bottle). Electricity. It's the biggest money's worth you can ever buy any- Warm the milk for baby day or night. where at any time. Send for It tcday enclosing 81.50. Magnetism and Send now before you forget. Pop corn, Theory of them The coupon below is a convenient way. But do it Protect houses from burglars. -and it's now. Amuse the children by running electric toys. FREE as THE' explained. EXPERIMENTER PUB. CO., Inc. Give electric baths in bath cabinets. Publisher Carry the family in the electric automobile. "The Electrical Experimenter Magazine." Purify the drinking water. Polish the floors (electric floor polisher). Dry the washing (electric drier). EXPERIMENTER PUB. CO., 233 Fulton St., New York Sterilize water or utensils. Gentlemen: Make ice -furnish refrigeration. On your absolute guarantee that your 20 Lesson Wireless Course is just as des- Play the piano. cribed by you, you may send me same FREE. You are to send me this Course at once, Mix family beverages. all charges paid, and enter my name for a full year's subscription to the Electrical Lift or lower dumb waiters. Experimenter, 12 numbers, for which I enclose *$1.50, the price of the Electrical Experi- Energize doorbells and annunciators. menter alone. Curl a woman's hair. (If a 2 -year subscription is desired, enclose $2.85.) Dry a woman's hair. AND run your wireless. My name is My address is (11) *Canada and Foreign Countries, $2.00 -2 years, $3.85. WITH THE "AD -MAN" IL Along about this time people commence to count up their loose change, and sharpen their pencils to make up their Christmas gift list and in general think of the approaching holi- EXPERIMENTAL ELECTRICITY days. And right here is where I'm going COURSE IN 20 LESSONS to ask you when making up your list that you consider how many of your By S. OERNSBACK and H. W. SECOR gifts can be purchased from adver- tlsers in THE ELECTRICAL EXPERI- MENTER ciA new course of the theory and practice of electricity for the experimenter. Wireless Apparatus of all kinds of course, watches, books, sporting This is undoubtedly one of the most complete and compre- goods, electrical apparatus, toys, hensive treatises on this special subject ever published. m. hearing devices and many, many other things. The book is written by the same authors as the now famous But there's one gift I'll bet you "Wireless Course in 20 Lessons." never thought of for a good friend m- or brother, one he will always bless Every phase of experimental electricity is treated compre- you for. It's a correspondence or resident course in some subject he's hensively in plain English. It is a book not only for the be- E ginner, but for every experimenter and student of electricity. anxious to learn. Yes, the course may cost more than you can afford, All the knowledge of the authors has been devoted to but at least you can make the first making the study of electricity simple to the layman. payment for him. Chances are you start him off like that and you will New Experiments are described and explained and nearly 6- in later years have the pleasure of every application of electricity in modern life is given in E knowing that you were responsible E for the rise in the world of one per - simple language. son. It is the most complete and practical course ever published, Is there any greater satisfaction in not only useful, but absolutely necessary to everybody giving than that? interested in electricity. By the way, if there is any information you want on any of the The book contains 160 pages, more than 400 illustrations. courses that are advertised in THE E- ELECTRICAL EXPERIMENTER or those that are not, just ask me and I'll be Cloth Bound (Special thin paper edition) Price, $1.00 glad to offer all the information I E. have available. DELIVERIES ARE NOW BEING MADE Try me and see. MILTON HYMES.

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o Scientific Exchange Columns you have at the present time some things for which you have no further use. Do you wish to exchange them UNDOUI3TEDLYfor something, for which you have immediate use There is no shier and quicker way to do this than by advertising your articles in these columns. The Very people, the Only people, who could possibly have a use for your things read this journal. More than 70,000 interested people will see your ad. It is furthermore the cheapest advertising medium for you in the country. Dealers' advertising accepted in Opportunity Exchange Columns only. The rates arc: Three cents per word (naine and address to be counted), minimum space 3 lines. Count about 7 words to the line. Remittance must accompany all orders. No advertisement for less than 50e. accepted. We reserve to ourselves the right to refuse any advertisement which we consider misleading or objectionable. Advertisements for the December issue should reach us not later than October 25th. The Classified Columns of "The Electrical Experimenter" Bring Positive Results. Subscribers experiencing trouble in dealing with any advertiser should notify the publisher very promptly. OVER 70,000 PEOPLE READ THIS JOURNAL

SALE OR EXCHANGE- Camera and outfit. FOR SALE or EXCHANGE-2,000 Stamp Col- OSCILLATORY SET -3 inductances. 4 vari- Cost $40.00. Send for Particulars and list of lection of rare varieties in good condition; want ables (Murdock's, Blitzen, Amco), Radio (Potts- Radio apparatus. Want sending transformer or wireless goods.. Albert Iljorth, Port Jervis, N.Y. town) coupler, $20.00. 3,500 mile range. J. McKenna, Shonnard Yonkers, what have you? Richard Anderson,. North SALE OR EXCHANGE -My new 1/6 K W. Terrace, N.Y. wood, NJ. Wireless Transformer. New Coherer, 1 K.W. EXCHANGE -E-flat Clarinet and Navy loose 65c. Aerial Switch. Will give 1/6 K.W. for audion coupler for 1 K.W. transformer, either open or BARGAIN -Three 116 -volt electric stoves. articles perfect A. each One electric iron, $1.25.. One $2.00 camera bulb. All letters answered. Jeter Pinkston, Val- closed core: Both condition. dosta, Ga. Ericson, 19 Bartlett St., Beverly, Mass. 75e. ' All goods guaranteed. Prepaid. Richard Gaillard; Pendleton St., Columbia, S.C. MOTORCYCLE WANTED -Will give $75.00 SALE OR EXCHANGE- Edison Standard Receiving Set $25.00 worth of other electrical Phonograph; 50 4- minute, IS 2- minute records. WILL TRADE new Tel -Radion for 43 plate apparatus and money. Write for proposition. Good condition. Cost $60. Would like audion variable, 1,200 meter loose coupler and 4-inch Van Pattillo, Hartselle, Ala. detector or amplifier. George Perkins, 365 Union spark coil for navy type loose coupler. Want St., Jersey City, N.J. K.W. Coil, Audion, Holtzer Cabot phones, LOOK4-25 Steven's rifle and jointed cleaning variables and other wireless goods. R. A. Ruble, rod, good as new, $5.50. Also Shaw's smoker FOR SALE- Two-inch spark coil, $5.00. Centralia, Wash. used twice, $2.50. Express prepaid. Ingman Claudius Burt, 102 Argyle Road, Ardmore, Pa. Ostrem, Perley, Minn. SELL $30.00 $20.00. THREE Audiotron Bulbs, never used, $5.00 WILL Receiving Set for each. Postpaid, Electro-selective Coupler, $5.00. 23 GLASS PLATE sending condenser, $2.00; Range 1,500 miles on suitable aerial. Write. Trade for Coupler. Polar relay or Meters. R. helix, $1.00, new and never used; fine 75 -foot Leroy Martine, North Bergen, N.J. G. Anderson, 7211 Indiana Ave., Cleveland, Ohio. aerial, 30e.; brand new pony receiver, 25e.; com- HAVE -1 K.W. Sending Condenser. $8.00; plete Hustler Motor, 25c. Rolston Bear, Hemet, 2 K.W. oscillation transformer, $8.00; marble FOR SALE -New Blitzen Variable Condenser, Cal. switchboard with switches; electrical books; $2.50. fixed condenser, 75c. Crystaloi Blitzen WANTED-A good headset in exchange for H.P. Ft. Wayne 60 -cycle motor; Roth rotary Detector Type AA, $2.50; with Buzzer and Test - converter, etc.. for sale or exchange for No. 3 -a ing Coil. $3.25. Murdock Coil, $1.50. a Victor Phonograph, also camera and outfit Tuning acetylene generator, two tennis racquets, ice and loose coupler or magnet wire. Write for descrip- 1 4-inch Bull Dog Spark Coil, $3.00. Spark Gap, roller skates, and postcard projector. Want tions. Ralph Batcher, 131 Ilyland, Ames, Iowa. 50e. Everything new, no trade. Richard Taylor, Roger Hack- 141 Lake St., Winsted, Conn. wireless apparatus or cash. Write. COMPLETE chemical outfit, High -grade C.P. ney, Wellington, Kan. chemicals. My large laboratory for sale at a bar- WANTED -Typewriter. Have 24 things in WILL SELL OR EXCHANGE for high -grade gain. Ralph Batcher, Toledo, Iowa. exchange. Send for list. A. Hofman, 382 Cor- postcard size, folding camera- one $8.00 2.-inch nelia St., Brooklyn, N.Y. FOR SALE- Wireless set, whole or parts. coil, one $3.00 Murdock 7-plate Variable Con- Send for particulars. Frank Plaisted, 142 Davis WANTED -AN independent interrupter to be denser. Terms strictly C.O.D. express, $7.00, Ave., Brookline, Mass. used on a 14 -inch Spark Coil. Will buy for cash no installment plan paying. Robert Haag, Chad- wick, Ill. FOR SALE -Chambers 748 Loose Coupler in or trade. R. W. Gates, 826 First Place, Plain- perfect condition. First check for $5.00 takes it. field. N.J. FOR SALE-Will sell my brand new Electro All other checks positively returned. Dean Car - FOR SALE-Small sending and receiving set. Loose Coupler and Loading Coil for $7.00. Both pentor, Westtown, Pa. No phones. are new this summer and in Al condition. Write. Cheap. Write for particulars. Elmer Stanley Batchelder, 82 Willard Ave., Portsmouth, WILL EXCHANGE -One $2.50 Perikon de- Raguse, Tottenville, Staten Island. N.Y. N.H. tector and foot -ball for one new Murdock Load- ing Inductance. Stuart Terrill, Brookfield Cen- FOR SALE OR TRADE -Vest Pocket Kodak WILL EXCHANGE $11.00 Omnigraph for ter, Conn. with leather case, $4.50. Remington Single Shot Brandes Transatlantic or other 3,000 ohm phones. Rifle, $2.50. Flashlight, 2 extra Batteries, 85c. FOR SALE complete receiving sets Must know make beforehand. J. Chaffee, Wood - -Two Premo Camera No. 0, $1.00. Want receiving mont, $11.00 and $22. Write. Cromer Heitslin, Kissel apparatus. George Coxe, Olean, N.Y. Conn. Hill, Pa. $275.00 -ARCO SL ABY open core 3 K.W. RECEIVER for spark or arc stations consist- SPECIAL BARGAINS-Large 115 volt D.C. Transformer, $45.00 1 K.W. Transformer, $5.00; Fan Motor for $8.00; Sensitive relay. $2.50; new ing of: $18.00 Chamber's coupler; double fila- 10 -inch Rotary Gap Wheel for sets up to 3 K.W. ment .25 calibre rifle for $4.00; Cover of $5.00 foot -ball $5.00, never been used; Panel and Coils wound audion cabinet complete; 2,000 ohm phones, for $1.75; Electric whistle. 50e.; Telegraph and tapped for cabinet set,set $10.00. Will make two months old, perfect condition. Also two sounder on marble, $1.00; Telephone receivers good trade for De Forest or tubular military type portable telephones with buzzer at- and transmitters each 75e.; Magnetos. $2.00 each; bulbs. Wm. Trumbull, 365 McGraw Street, Se- tachment, good condition. What offers or ex- 2.000 ohm ringer for $1.00; non -breakable po- attle, Wash. changes? W. A. Brooke, 3127 North 13th St., tentiometer, 75c. All Write Philadelphia. in Al condition. FOR SALE TRADE for particulars. Clarence Kositzky, 911 South OR -$35.00 Shell Lake FOR SALE -Receeiving Ninth St., Lincoln. Neb. Canoe in Al condition, used three months, for Set, complete, with Thordarson or Packard i K.W. Transformer or aerial and parts. Price $10.00. Schorr, 330 FOR SALE -Knapp dynamo-motor, $3.00; anything you have. All letters answered. Frank Essex St., Brooklyn, N.Y. tuning coil, $1.25; telephone magneto, $2.00. Gerster, Havana, Ill. FOR SALE OR EXCHANGE - "Electro" High Trade fou good double headset or variables. Tension Adjustable Raymond BUGS! -Big Bargain if you buy my complete Condenser; "Electro" rotary Gerich. Rich Hill, Mo. sending and receiving Outfit, aerial included, Potentiometer; Radioson Detector with used cartridge; "Electro" Helix with pilot lamp. Want FOR SALE -9 volt 15 amp. generator, $10.00; cost $30.00 sell for $20.00. Write for particu- *inch spark coil, $2.50. Paul Watson, 214 lars. Fay Williams, Huron, Ind. "Gernsback" or good 43 -plate Variable. Cash for West Barnard. West Pa. Variable. Louis I enfer, 443 E. 85th St., New Chester. SACRIFICE -First $20.00 gets two audions York City. FOR SALE OR TRADE -Never been used, and board; two variable condensers; one fixed condenser; one tuning coil; WANTED -% K.W. Packard transformer in $7.25 receiving transformer, 3,000 meter, $6.00; one potentiometer, perfect condition. State price. All letters an- $3.50 Turney variable condenser, 35 $3.00; also one combination galena silicon carborundum plate, etc. swered. John Q. Adams, 5424 Fulton St.. Chi- 70c. fixed condenser, 50c. I want Corona type- detector. All guaranteed in excellent con- cago, Ill. writer, Audion detector, Audiotron bulb, aerial dition. Write for particulars. R. W. Hoffman. material or what have you? George Dimon, 367 4011 Greer Ave., St. Louis, Mo. FOR SALE -Electric Therapeutic Apparatus Genesee St., Utica, N.Y. or willing to exchange for a high frequency ap- $15.00 LOOSE COUPLER, $5.00; $7.00 Clapp - paratus for a Eastham Ferron Detector, $2.50; very reasonable difference. Kindly TO SWAP -Old gun valuable as relie, shot Omnigraph, call at 364 \Vest 67th St. or 113 West 63d St. gun and rifle, also books for wireless apparatus. 75e.; D.P.D.T. Switch, 75e.; Buzzer; Push Bind- on Sunday. John Ferguson. Write. Robert Holverson, Kasota, Minn. ing Posts; Mineral; etc. FIRST Money order for $10.00 gets everything. Robert Boehner, FOR SALE-5 -inch Induction Coil in fine con- MAGAZINE WANTED - Will pay cash for Brookline, Mass. dition, $20.00; new 6-80 storage battery. $10.00; any back numbers or hound volumes of Aero, 1 /10 H.P. compound wound 110 V. D.C. motor, FOR 1 Aeronautics, Aircraft, Flying, Electrical Experi- SALE-$12.00 K.W. rotary, cost $6.00. Want 3A Kodak or Graflex Camera. W. menter and Wireless Age. State price. L. $17.50: $7.00 '4 K.W. antenna switch, cost $3.00. S. Wells, 6626 S. Marshfield Ave., Chicago, Ill. Koerner, 312 W. St. Vrain Write for particulars. J. S. McDonnell, Jr., St., Colorado Springs, 3304 Eighth Ave., Little Rock, Ark. FOR SALE- Mignon RLC6 receiving cabinet, Colo. practically WANT racing bicycle attachment motorcycle new, cost $75.00. My price $60.00. FOR SALE -Rotary spark gap. never used. RJ9 Audion detector, never been used, $12.50. operates on engine. Have athletic and wireless goods. Lau- R. M. 6 volts. F. C. Cave, Winfield, Kan. rent. 405 Fulton, Canton, Ohio. Richert, Statesville, N.C. WHAT am I offered for a 3 H.P. Reading SALE OR EXCHANGE-Two comolete send- EXPERIMENTER-Until November fifth, Standard, single cylinder, motorcycle engine? $17.00 buys $27.00 complete receiving set con- Will ing and receiving outfits. All kinds of Electrical take wireless instruments, cash or both. Apparatus sacrificed. Want audion or bulb; sisting of Lightning Switch, Antenna Switch, Send stamp. R. B. Wailes, 3118 14th St. N.\V., Murdock 2,000 ohm headset, Arlington Loose Washington. switches: storages, etc. Write; all with stamp D.C. answered. Frederick McMullen. Fairchance, Pa. Coupler, Turret Cup Detector with crystal, Pre- cision loading coil, fixed condenser, fixed vari- FOUR SALES-4-inch spark coils, perfect SALE OR EXCHANGE- Camera, Kodaks, able condenser and rotary variable. Each piece condition. giving large spark, 65c. each. Adrian Kishpaugh, Newton, Minute Machine; Phonograph, Musical Instru- reliable. G. R. Campbell, 207 Grant Ave., Belle- N.J. ments. Write. S. Copeland, Ahoskie, N.C. vue, Pa. Ycu benefit by mentioning "The Electrical Experimenter" when writing to advertisers.

www.americanradiohistory.com 544 THE ELECTRICAL EXPERIMENTER November, 1916

SALE OR EXCHANGE- Dynamo, 1/4-inch coil, WILL EXCHANGE -A complete "Telegra- FOR SALE-Or will trade a 15 K:W. high medical coil, magic lantern, Pony receivers, phone" talking and reproducing head for use in voltage transformer with rheostat and switch books, small phonograph. Want: 110 V. motor, recording radio messages on a moving steel wire board for a Hytone transmitting set. Write. Victrola, storage battery, tools, wireless sundries, or band. Also a finely calibrated Keystone milli - Harry Cole, 1515 Linwood Blvd., Oklahoma City, etc. What have you in any line? Send stamp. ampere meter excellent for radio measurements. Okla. Orville Huish, 140 Byron, Youngstown, Ohio. Will exchange the above for any of the follow- FOR SALE- Complete Wireless Outfit; 34 KAY. WILL TRADE- Electric postcard projector ing: A.C. or D.C. volt or ammeter, referably of Transformer, Clapp -Eastham Receiving Cabinet with 110 V. bulb for 1/4-inch spark coil. the Keystone or Weston make; smallpA.C. motor, 3,000 Ohm Phones. Cost over $75.00. Will sell Miller, La Harpe, Kan. '/y K.W. tranysformer, or what have you? Samuel for $45.00. Send for particulars. Harry Anders, BARGAINS- Instruments are practically new. Cohen, 1936 Pitkin Ave., Brooklyn, N.Y. Decatur, Mich. Loose coupler, $5.00. Double slide tuner, $L25. RADIOSON DETECTOR, new, for sale. See FOR SALE OR EXCHANGE-Two absolutely Detector. 75c. Money back if dissatisfied. G. description in Electro Importing Co.'s catalog. brand new Electron Relay Bulbs, positively never N.J. $2.75 M. Lesher, East Orange, First money order for takes it. Edward used, each $3.25 4 Bar Telephone Magneto and WILL EXCHANGE for wireless goods, a com- Jones, 522 Fairmont Ave., Fairmont, W.Va. Case, $3.50; 1 Î:K.W. Gap 40c.; Tillotson Tele- plete course of 20 lessons in IIypnotism with WILL EXCHANGE-New 6 volt 180 ampere graph Sounder, $2.00; Variometer (Home made), other scientific matter. A. Bozinsky, 339 E. 47th Willard Storage Battery for De Forest Audion $L24; E. I. Co. Fixed Condenser, 50c.; Rotary St., New York City. Detector, and Amplifier or Two Step Multi -Audi- Gap Disk, $1.35; Helix (Home made), 12x12 FOR SALE-Brandes Superior single headset, Fone; must be in good condition. Have Type O inches, $1.50; two 60A600V SPDT slate base $2.00; Amco % K.W. closed core with primary Crystaloi Detector and Resonator, used two fuseless switches, each $1.00. All except switches variation, used one month. $10.00; small coupler, months, $2.00; Manhattan adjustable primary prepaid. L. B. Stratton, Oneida, N.Y. $1.00, Lee Hodges, 3408 Duvall Ave., Baltimore, condenser, used two months, $3.00. \Vhat have WILL TRADE -Smith Motor Wheel in 19 good Afd. you? Bruno J. Warsh, 718 W. Place, Chicago, condition for 54 K.W. Sending Set, complete, GENERATOR C.P. 32 V. 20a direct connected Ill. with rotary gap. Vernon Wise, Butler, Pa. to 2 H.P. Motorcycle Engine for good collection FOR SALE -Ive's Electric train, $4.50- 40 FOR SALE -15,000 meter tuner, $10.00; tele- of U.S. and Foreign Postage Stamps. Petticrew, watt Dynamo Motor, $4.50 (new), Baldwin Camp graph set, $1.50. Other apparatus. Edward 133 Gunchel Ave., Dayton. Ohio. Lamp, $1.50, Steam Engine, $1.50. Might trade. Silver, 264 West 57th St., New York. William Van Akin, Liverpool, N.Y. WANTED -Best sending set for $10.00. Give MUST SELL -New Crystaloi detector type A, description, range, amount used. Wm. M. Crane, FOR SALE -Oliver No. 3 Typewriter, Mmost $1,75; E. I. Company Transatlantic 1,000 ohm Richmond, Mass. new, $23.00. Also have camera, photo, tent, rifle phone and cord, $1.50; new 6 volt 60 ampere AUDION AMPLIFIER -Good bulb, used 3 and watch at bargain prices. Joseph O. Berg, Willard Storage Battery, automobile, type, used hours, cost $65.00. Sell for $35.00. Browne, Hendrum, Minn. two months, $9.80, cost $17.50; 154-inch box type 384 Mott Ave., New York City. FOR SALE OR EXCHANGE- International spark coil $5.60, cost $8.00; Hydrometer, 65e.; COMPLETE sending and receiving station Correspondence School's course in arithmetic, 6 volt 4 ampere Knapp dynamo motor, $2.90; cost $52.45, practically as good as new; will sell also electrical books and apparatus, cheap, Alex. Switchboard, 2 double pole switches, 2 single pole for $35. Send for description. J. E. Matson, Serna, Lehigh, Okla. hard rubber switches, rheostat, ammeter. All very neatly mounted on stained wood base, Neola, Iowa. FOR SALE -A first class Wireless Sending $4.80; Receiving outfits, double pole double throw 30 ampere antenna EXCHANGE- -New " Electro" Transcontinental and Outfit. Two sending switch, 90e.; electric thriller magneto shocking Erector set No. 4 and a Microscope Outfit. Make Outfit No. 1603. Want good typewriter. Forrest machine, 50e. All articles have been used only a Elwell, De Veaux College, Niagara Falls, N.Y. offer. Enclose 2c. stamp. John flouhy, Matta - pan, Mass. very short time have been well taken care of FOR EXCHANGE- Combination Edison fire- and are as good as new. Special $2.85 foot -ball side phonograph (new) and 45 four-minute rec- COMPLETE Wireless receiving outfit loose without bladder, $L45, used once, guaranteed ords, value $35.00, for complete receiving set of coupler; condenser; 2,000 ohm phones; loading. good as new; Stevens .22 target rifle, $2.40, cost equal value. P. B. Smith, 298 Bond St., Bridge- coil; telegraph key and sounder, all $7.00. $4.75, used very little. Roy Sprecher, Lancaster port, Conn. Shartle, 575 West 172d St.. New York City. No 5. Pa. - J.gql ',,.. Opportunity Exchange OU will probably find more opportunities and real bargains in these columns than anywhere'èlse in the country. Most good things in \7 life are hard to find and worth going after-these little ads illustrate that point; you alone will be the real loser if you don't take the time to scan through these columns. Advertisements in this section 4c. a word for each insertion. Count 7 words per line. Name and address must be included at the above rate. Cash should accompany all classified advertisements unless placed by an ac- credited advertising agency. Ten per cent, discount for 6 issues, 20 per cent. discount for 12 issues from above rate, Objectionable or misleading advertisements not accepted. Advertisements for the December issue should reach us not later than October 25th. OVER 70,000 PEOPLE READ THIS JOURNAL EXPERIMENTER PUBLISHING CO., INC., 233 Fulton Street. New Vnrk. N.Y.

BOOKS PATENTS SECURED OR FEE RETURNED WIRELESS -Send sketch or model for free search and re- Latest book free. HAVE YOU SEEN A COPY?-Amateur port. complete patent George DOUBLE filament audiotron bulbs, $4.50 each. Photographer's Weekly, $1.50 per year; weekly P. Kimmel, 254 Barrister Bldg., Washington, D.C. Full directions for making a Wireless Telephone prize competitions- criticisms; print exchange; given with each bulb. Leon Bartholomew, 313 illustrated; many features. Three months' sub- Deyo St., Jackson, Mich. scription 40c. Amateur Photographer's Weekly, IDEAS WANTED -MANUFACTURERS are 915 Schofield Bldg., Cleveland, Ohio. writing for patents procured through me. Three books with lists of hundreds of inventions wanted STRANDED TUNER WIRE for receiving BOOKS- Scientific and wireless supplied. Let sent free. I help you market your invention. ARC and LONG DISTANCE -10 copper enamel us know what you want and we will quote you. Advice free. R. B. Owen, 130 Owen Bldg., Wash- wires covered with silk at lc. er yard, 20 wires Experimenter Pub. Co., 233 Fulton St., New ington, D.C. 2c., state whether No, 36 or No. 38 enamel wire York City. is desired; discount on '/s and 1 pound lots. PATENTS BRING RICHES -Protect Your Special sizes to order. J. H. Claus, Hulmeville, A BINDER for THE ELECTRICAL EX- Invention. Attorney's fee payable when patent a. PERIMENTER will preserve your copies for all allowed. Plain advice and "Patent Facts" free. on 3 lbs. is extra. Trademarks registered. Jaynes & Jaynes, 501 time. Price 50c. Postage RADIO QUESTIONS answered, 3 10e.; 9 Send one to-day. Experimenter Pub. Co., Kellogg, Washington, D.C. for for for 25c. Cat wiskers, 4 for 7c. Walter Patch, 233 Fulton St., New York City. Iowa. PATENTS -Personal attention to all inquiries. Ventura, MISCELLANEOUS No printed literature. No lists of Inventions Wanted" -Such being unauthorized by the Pat- TELEGRAPH -Morse and Wireless, also Sta- ent Office. Fees reasonable, consistent with best FORMULAS GUARANTEED MONEY- tion Agency taught. Graduates assisted. Cheap -60 results obtainable. Electrical and Mechanical Ex- expense, easily learned. Largest school, estab- MAKERS, 10e. Catalog for stamp. "IDEAL,' pert. J. Edwards Bangs, Suite 408 Barrister (EE) Irving Station, Chicago. lished 42 years. Correspondence courses also. Bldg., Vashington. D.C. Catalog free. Dodge's Institute, Lone St., Val- STAMPS -75, all different, free. Postage 2c. paraiso, Ind. Mention paper. Quaker Stamp Co., Toledo, Ohio. PHOTOGRAPHY UNUSUAL BARGAIN-Rotary Converter op- MAGIC GOODS PUZZLES. Big -TRICKS- FILMS DEVELOPED FREE -Send negative erating on 110 volts D.C. and having an output catalog free. C. Hagen, 2423 Winnemac Ave., of 85 volts, 11 amperes, at 60 cycles. Operates Chicago. for sample print and particulars. New Lex Nov- elty Co., New Lexington, Qhio. /z K.W. transformer perfectly. Is unusually small; size 81/4x9x11 inches; weight 64 lbs. Has TRICKS PUZZLES MAGIC GOODS - - MARCONI -We have a limited supply of pic- regulating, rheostat 12x13x6 inches weighing 29 GAMES-NOVELTIES. Sample and catalog 3c. lbs. and is an ideal equipment for experimental Ideal Magic Shop, (EE) Irving Station, Chicago. tures of Guiglielmo Marconi that are done in sepia on fine India paper. Fine for decorating purposes. Price complete $35.00. Electro Import- yourour wireless room. Ten cents each postpaid. ing, 236 Fulton St., New York City. PATENT ATTORNEYS r menter Publishing Co., 233 Fulton Street, New NAVY TYPE COUPLER and loading coil AMERICAN AND FOREIGN PATENTS ob- combined, tained. Before selecting an attorney, write for PHOTOGRAPHY $12.00; 2,500 meter coupler, $5.00; WITHOUT CAMERA- other bargains. Cliff Mfg. Co., Brookfield, Mass. our solid, instructive advice; oin the ranks of Novel social pastime, using photo paper invisibly happy inventors. Correspondence Office, 125 prepared with interesting and artistic pictures. East 23rd Street, New York City. F. V. Winters, Samples prepared for 25 pictures with directions, MOTORS-Rebuilt at extra low prices. 1/6 Reg. Patent Lawyer. New York City and Wash- 10c. Wedge Mfg. Company, "Km," Binghamton H.P. 110 V. D.C., $6.00; 40 Watt, $4.00. A. J. ington, D.C. N.Y. Temps, 1690 Grove St., Brooklyn, N.Y. You benefit by mentioning "The Electrical Experimenter" when writing to advertisers.

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