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The "SUPERIOR" Type Note these specifications: The case is one piece of polished aluminum 4" in diameter and 4" high. It may ho filled with oil with- out leakage, and this Increases its capacity Price, Complete, Five Dollars approximately live times. There are 31 aluminum plates, 1G station- ary and 15 rotating. These are fastened to a q This is the headset used by Mr. Chas. E. Apgar in polished fibre top which fits tightly over the conjunction with his special apparatus for making case. The top is provided with a celluloid scale, pointer, knurled knob and binding the phonographic records of the Sayville station as posts. described page 210 in The maximum capacity, without oll, is on August issue of the Electrical .003 31íd. Experimenter. Mr. Apgar chose Brandes Receivers It is particularly adapted for a series con- denser in the primary circuit of a coupler. after careful comparative tests with other makes. After reading the above you must agree with us that we have an unusual article at Send stamp for catalogue "E" fully describing all our headsets. an unusual price. Send for No. 3.1r2 .lPinny Condenser at $2.50, postage extra. shipping weight, Ih=. Delivery from Wireless Receiver Specialists stook. Circular of our complete line ou C. BRANDES, Inc., reym.=t. MAGUIRE & SHOTTON

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Von benefit by mentioning "The Electrical Esperimenten" when writing to advertisers. www.americanradiohistory.com The Electrical. Experimenter Published by Experimenter Publishing Company, Inc. (H. Gernsback, President; S.. Gernsback, Treasurer; M, Hymes, Secretary), 238 Fulton St., New York Vol. III Whole No. 30 CONTENTS FOR OCTOBER, 1915 No. 6

FRONT COVER -"AURORA BOREALIS." From painting by AN ELECTRO- MAGNETIC NAIL- PACKING MACHINE Thom. N. Wrenn. By F. C. Perkins 259 THE AURORA BOREALIS OR THE NORTHERN LIGIITS ELECTRICITY ON GERMAN SUBMARINES 280 By II. Winfield Secor 243 MARCONI HEADS WIRELESS CORPS OF ITALIAN ARMY 281 BARON MUNCHHAUSEN'S NEW SCIENTIFIC ADVENTURES. A NEW ELECTRICAL PHOTO PRINTER 281 By Hugo 246 HOW THE "MOVIES" EXPLOIT WIRELESS 262 Gernsback LARGEST STATIC MACHINE IN THE WORLD 283 THE GRAVITATION NULLIFIER. (A Scientific Story.) ELECTRIC SPARK PICTURES -HOW TO MAKE THEM 285 By George Frederic Stratton 249 NEW TELEPHONE SET FOR AVIATORS 266 CONSERVING UNCLE GEORGE By Thomas Reed 252 ELECTRICITY AND THE MODERN AUTOMOBILE TORPEDO TRANSFER THOUGHT WAVES, 253 By Samuel Cohen 287 CAN ELECTRICITY MODERN APPLICATIONS OF THE LOUD SPEAKING TELE ELECTRIC TOYS THAT RESPOND TO THE VOICE 255 PHONE 268 A LIGHTHOUSE OPERATED AND CHECKED BY ELECTRICITY "THE CONSTRUCTOR" DEPARTMENT 289 By E. O.. Catford 256 "RADIO" DEPARTMENT 278 ELECTRIC DENTAL SIGN THAT DEMONSTRATES "BEFORE" RECEIVING WIRELESS MESSAGES WITH ODD AERIALS...274 -275 AND "AFTER" EFFECTS 256 "HOW -1'O- MAKE -IT" DEPARTMENT 282 INSTALLING A COMPLETE ELECTRIC SERVICE IN FIFTEEN WRINKLES. RECIPES AND FORMULAS. Edited by S. Gernsback 286 MINTES 257 "WITH THE AMATEURS" 2.287({6 TELEPHONE THAT TELLS WHO CALLED WHILE YOU LATEST PATENTS 289 WERE OUT 258 PIIONEY PATENTS 289 A TELEPHONIC NURSEMAID AND A BIRD ALARM QUUESTION BOX 290 By F. C. Perkins 258 PATENT ADVICE 296

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C F W'G hávèAOften had- óccasion to feel amused at to exist in France and Belgium, according to the best t é blank -astonishment of the average well- authorities. informed European when he first spies the In Germany, Austria- Hungary and Russia amateur hundreds of aerials which now decorate a Wireless is absolutely unknown. There have never been multitude of houses in our cities. When we inform the any amateur Radio stations in these countries to the stranger that, according to trustworthy statistics, there best of our knowledge. The governments of the above are now between 350,000 and 400,000 purely amateur countries are exceedingly strict in the transmission of Wireless stations scattered all over the United States, intelligence by Radio telegraphy and no, licenses are there is no end to his wonder. ever granted, with the exception of those to savants and This is not surprising if we consider the fact that to a few universities. But even here the restrictions the United States to-day is the only country that places are formidable. practically no restrictions upon the Wireless amateur. The rest of the world. with the possible exception of Iii America everybody is allowed to put up a Radio a few South American countries where less than 200 receiving station, and while a license must be obtained stations flourish, measures up poorly as far as the for sending messages the regulations are far from Wireless amateur is concerned. It is believed that out- severe and any intelligent youth, as a rule, finds it com- side of the countries named there now exist less than paratively easy to obtain the coveted license. 300 amateur radio stations. Outside the United States there are, therefore, considerably less than 15,000 such Now let us turn to other countries. Of course, during stations. In other words, there are in America twenty - the war in the affected countries no amateur stations five times as many amateur Radio stations as in the are allowed to operate, the penalties for the offenders entire world. It is, indeed, a surprising result and being extremely severe and usually a long term of speaks well for the enterprise of American imprisonment is meted out to the unlucky operator. the ex- perimenters. The conditions prevailing before the war and which Nor can the average European understand will presumably prevail again after peace is re- estab- of what earthly good the lished are briefly these: youthful Radio amateur is, for he argues that Great Britain and its dependencies: No Wireless correctly not all of them can possibly be- come amateur stations can be erected without the consent of commercial operators. But he forgets that the the Postmaster General. In Australia, previous to the average amateur must of needs have a higher intel- war, amateur Wireless was all but suppressed. Of ligence than his card -playing, dance -hall -resorting class- England's colonies Canada probably has the greatest mate. Indeed, when your average Radio amateur has Wireless freedom, although a license from the Post- mastered all the intricacies of a Wireless set, he has master must be obtained. In Great Britain proper, it obtained a pretty thorough knowledge of electricity in has been estimated that not more than 2,000 amateur general. As a rule, most of our electrical industries, Wireless stations prospered before the war. In France big and little, require thoroughly practical young men, and its colonies and in Belgium the same conditions the ones who know how to do. things. This is where prevailed as in Great Britain. It seems, however, that the amateur shines, and nine times out of ten he lands the French amateurs, just previous to the outbreak of the job over the head of the untrained, theoretical the war, engaged in a petition to the Government, plead- young man. íJ.. ing for greater Radio freedom. Results of the petition For this reason American parents, as a rule, encour- I) are unknown at this time. Of all the foreign amateurs age their son, for they know that he does not waste the French are probably the most active. Before the' his time. The amateur wireless station seems to be a L! war some 1,500 amateur Wireless stations were known first -class investment. H. GERNSBACK. l!J

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A spring rests on the ball in the hollow standard and This Rotary Spark ';'p emits a high musical note, more audible to the human ear, sets into a cup under the adjusting screw, so that varying pres- can he beard at greater distances sures can he had as circumstances require. Remains permanently than the note from the station- in adjustment under jars and vibrations of every description. ROTARY ary type, and cannot he mistaken for static or other atmospheric SPARK GAP disturbances, a fault common The Codegraph Plate is of CODEGRAPH with the statiouary gap due to metal, with insulated dots and low frequency note. The Pen is connected The rotating member has dashes. twelve sparking taints mounted in circuit with the Red Seal N on a hard rubber disk and is Dry Battery and the Wireless r.11lAlS7Wa MEW WEI carried on the motor shaft. Also fitted with two stationary Practice Set. When the pen is tarlIMIIKREFPN*WWEEI electrodes with special adjusting drawn across the dots and liRlZtirl!G3_lr,FEwrizt devices. dashes it closes the circuit and !MIESIEB11! I The Gap can he successfully lfttf7ifAis3RIElt_31® used on any of our spark coils the huzzer sounds. It is pos- RAIRE117E9lS1tiWEEtL0 or transformers up to and in- sible to attach a sounder to the cluding 1 K. W. capacity. outfit and get the telegraph Our standard Globe \toter is used, which will click also. A practical and y operate on 110 A. C. or D. C. circuits efficient way of learning wire- and attains a speed of 4,5011 less and telegraph signals. R.P.M. Also made with our Globe Battery M toe, w hieh can be operated on a six -volt circuit. List No. Price List. No. Price 303 Mesco Codegraph Set $2,50 Mesco Rotary Spark Gap, 6 volt $12.00 223 Mesco Rotary Spark Gap, 110 v., A. C. or D. 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H. G ER N 5 B ACK EDITDR H. W. 5ECDR A5512C114TE EDITOR

Vol. III. Whole No. 30 OCTOBER, 1915 Number 6 The Aurora Borealis or the Northern Lights By H. Winfield Secor THE Aurora Borealis, or as it is com- Auroral effects take place, or at least no Contrary to general belief the strength monly known, the Northern Lights, sound that can be attributable directly to of the light given forth by the largest constitutes one of those great scien- them. Several explorers and scientists Auroras is much inferior to that of the tific problems which bid fair to puzzle the who have studied this phenomenon closely full moon. This fact is mentioned by those keenest wits in their solution for years to mention distinctly that sounds have been who have studied the Aurora in the North- come. Those of us who live in the tem- heard simultaneously when these Auroral ern regions at close range. Tests carried perate or tropical zones of the earth have effects occur, but in many cases, and quite out by reading a printed page, etc., prove probably never witnessed to any great ex- possibly in all cases, therefore, these sounds that generally speaking the maximum light tent, the truly indescribable and marvel- were found to emanate from such causes from the Aurora Borealis rarely exceeds ously beautiful color that of the moon in effects, produced by its first quarter, which the Aurora Borealis, is, of course, quite or also by the Aurora weak, or in other Australis. When these words, reading an spectacular effects of ordinary book page nature are seen in the was just possible. The neighborhood of the duration of the North Pole, or at Aurora display may least in that direc- be but a fraction of tion, they are known an hour or it some- as the "Aurora Bor- times exists for sev- ealis." When seen eral hours, fluctuating in the vicinity of the all the while. South Pole or in that The color of the direction (with re- Aurora Borealis is spect to the observer's one of the least un- location), they are derstood at the pres- termed the "Aurora ent day by the lay- Australis." man. In general it is The word Aurora usually composed of Borealis (and refer- more or less vivid ring to the northern red, yellow and green polar lights, frequent- shades. The front ly observable in the cover illustration, re- heavens), was first produced from an oil used by Gassendi in painting especially the year 1621, or so painted for the Elec- our science books tell trical Experimenter, us. Fig. i. Beautiful Ribbon Effect of Aurora Borealis When Viewed at Clo se Range in Northern shows some of the Up until the last Countries. enchanting beauties century there were o f this wonderful many wild tales published in various parts as the shifting of large ice fields, the con- display produced by nature and which has of the world with respect to the Aurora tinual changing of large snow deposits or been viewed only in all its magnificent Borealis and as to what it looked like, as other minor sources. pristine glory by very few men indeed, as well as to the other physical properties As regards the matter of any distinct such a worthwhile view is obtained only by manifested by this little understood pheno- odor or smell noticeable from the Aurora making a pilgrimage to the regions ad- menon occurring in nature. It is generally Borealis effect some authorities have jacent to the North Pole. conceded ' to -day to be an electrical dis- claimed that there is discernible a dis- The above mentioned painting is the only charge taking place through the highly tinctly irritating odor similar to that pro- one in existence to our knowledge showing rarefied upper atmospheric strata surround- duced from "ozone," or practically speak- the Aurora Borealis in its true colors. It ing the earth. Although many writers have ing the same as we all have noticed after was originally conceived by Mr. H. Gems- claimed that there is a distinct sound ac- a heavy thunder storm has passed. The back who is responsible for its accuracy; companying such Auroral discharges or "ozone" in this case is due to the light- it required several weeks of careful as well demonstrations it is pointed out in most ning discharges striking through the at- as painstaking work in order to enable the reliable scientific works on the subject that mosphere and purifying same. Ozone is talented artist, Mr. Thom. N. Wrenn, to there is no sound noticeable when these thought to be a certain form of oxygen. start the painting. Several experts on the TEE ELECTRICAL EXPERIMENTER is published on the 15th addressed to: Editor, THE ELECTRICAL EXPERIMENTER, 23$ of each month at 233 Fulton Street, New York. There are 12 num- Fulton Street, New York. Unaccepted contributions cannot be re- bers per year. The subscription price is $1.00 a year in 11. S. turned unless full return postage has been included. ALL accepted and possessions. Canada and foreign countries. $1.50 a year. contributions are paid for on publication. A special rate 1s paid U. S. coin as well as U. S. stamps accepted (no foreign coins or for novel experiments; good photographs accompanying them are stamps). Single copies, 10 cents each. A sample copy will be sent highly desirable. gratis on request. Checks and money orders should be drawn to THE ELECTRICAL EXPERIMENTER. Monthly. Entered as order of THE EXPERIMENTER PUBLISHING CO., INC. If you second -class matter at the New York Post Office, March 1. 1915. change your address notify under Act of Congress of March 3. 1879. Title registered U. S. us promptly, in order that copies are Patent Office. Copyright, 1915, by E. P. Co., Inc., New not miscarried or lost. A green wrapper indicates expiration. York. The All contents of this magazine are copyrighted and must not be repro- communications and contributions to this journal should be duced without giv-ng fí:11 credit to the publication.

www.americanradiohistory.com 244 THE ELECTRICAL EXPERIMENTER October, 1915

Aurora including Mr. Arctowsky, of New a fair idea as to how the Aurora Borealis over many widely scattered parts of our York, were consulted during that time. extends upwards into the sky in the form globe. Also in conjunction with these A good idea as to the general appear- of a ribbon or waving sheet. This ribbon large solar spots and magnetic storms ance of the Aurora is best had by quoting formation is made up of a myriad of there are invariably produced very bril- a few words from Alexander Von Hum- flashes or stripes, so to speak, which are liant Aurorae. boldt, the famous explorer, who had the continually changing in intensity and color Prof. Arrhenius believes that the cor- good fortune to witness a number of excel- value, being of a bright red at their 'base, puscles emitted by the sun are not incon- lent Auroras at close range. yellow at the center and green at the top ceivably minute bodies, but that they do usually. When viewed through have an appreciable size. For instance, let the "spectroscope," the light us say they are 1 /1,000 millimeter or of the Northern Aurora ap- 1/25,000 inch in diameter. Furthermore, pears a vivid green and its that these corpuscles are expelled from the wave length has been :.._Stil estab- sun by the repulsive action of radiant light. lished a ++di II,. to have value of 5,570 Also that such radiant light in thus cap- standard units. able of propagating or thrusting particles .l Sir William Ramsay, t h e out into space in spite of the enormous . noted English scientist, made gravitational pull of the solar planet. This a number of laboratory tests latter fact has been demonstrated a num- some time ago with vari- ber of times in the laboratory, viz., that it ous gases, notably Krypton. is possible for light to exert a distinct When electric discharges force. Again, Profs. Nichols and Hull were passed through t h i s have experimentally proved and demon- gas, there was noted, when strated that light does exert pressure to a viewing it through a spectro- very marked extent, relatively speaking, ,- scope, and therefore there seems to be nothing . a vivid green light, similar to that produced by inconsistent with Arrhenius's hypothesis. ,1. the Aurora Borealis, and its Whether we like to accept the theories lt wave length was ascertained of Birkeland or Arrhenius as correct or ,i II r;1 I to be 5,570.5 standard units. not, it does seem quite possible that nega- , . are On the strength of t h i s tively electrified gaseous molecules . r. 11P phenomenon Sir William present in the upper strata of the atmos- Ramsay believes that the phere surrounding the earth. Also it seems tC Aurora seen in nature may quite likely that these molecules receive ' most easily where they f r undoubtedly be produced by their electric charge ,ti;, electrical discharges (in the are most exposed to a vertical sun. In at the equator, rt upper rarefied atmosphere of other words, this would be the earth) and passing or nearly so. These upper aerial currents, (, through a gas in which Kryp- so to speak (and according to the theory ton is present to a large ex- of Prof. James Thomson), will carry these :. tent. and other molecules towards the earth's

! . t magnetic poles, designated as the North As regards the scientific and South Poles, respectively. These molec- theory covering the possible ular streams would mo.ve spirally north- nature of the phenomenon ward and southward with an easterly aiidtu-- known as the Aurora Bore- trend. As they approach the vicinity of alis, it may be said that prac- the magnetic poles of the earth, their num- ..rF tically all of these now de- . ber per unit area would quite obviously be W ...,.,q pend upon some electrical greatly increased, owing to the fact that the discharge action for t h e i r terrestrial parallels of altitude degrees grow 1-..> basis. In fact, as early as less in circumference, the closer they are .it....,, 1714, Halley, the famous,as- to the "poles." It can also be expected, tronomer, hazarded a guess we are led to believe, that before the mag- Fig. z. The Aurora Borealis Resembles a Mighty Curtain that the Aurora Borealis was Flapping in the Breeze. netic "poles" themselves are reached the a magnetic phenomenon, due potential of the upper air should increase to the electrical charge ex- to so marked an extent as to produce a Says this scientist, "Consider that the isting on the earth and also in the air distinctly apparent luminous electric dis- sky becomes at first slightly overcast and above it. charge. This luminous discharge more- a little later a dark segment seems to form There are two principal theories now over being in the form of a ring or halo in the firmament overhead. This dark worth considering which endeavor to ex- about the magnetic poles of the earth. segment passes from the form of a dark plain the whyfore and the where of the This particular fact has been noticed by shadowy cloud into a beautiful brown or Aurora Borealis. One of these is that due most of the explorers and investigators of violet shade. A broad, brightly luminous to Prof. Birkeland, of Christiania, Norway, the Aurora Borealis. It is this ring or arch is noted, which slightly encircles the and the other comes from Prof. Svante dark segment. This arch remains some- Arrhenius, of Stockholm, Sweden. times for hours together, flashing and To elucidate, it may be said that we have kindling in a marvelous and ever varying long known that violet light rays, and par- anode series of undulations before rays and ticularly the invisible rays of the ordinary streamers branch out from it, shooting up- spectrum beyond the violet (which are fx/,ous/ed bedb ¡ ward toward the zenith. The more in- easily detected by photographic means), ...... tensive the discharge Northern possess property discharging a nega- of the the of i flIIIIIIIIIIIIIIIIIIIIIII Lights, the more bright is the play of tively electrified body. It is suggested by IIIIIIIIIIIIIIIIIIIIIIIIII colors, furthered by the variety graduation Prof. Birkeland that the spots on the sun from violet and bluish white to green and are caused by solar eruptions, and that the crimson. If the observer is fortunate, as sun is then caused to give forth an ex- some have been, he may perchance see the traordinary amount of negatively charged 0 most wonderful sight possible for any corpuscles, not unlike those which constitute Fig. 3. Producing an Artificial "Aurora Borealis" human, or that known as the Crown of the cathode rays. These rays are similar In the Laboratory. the Northern Lights. This effect is caused to those utilized for surgical practises in by the rays or streamers darting upward taking X -Ray pictures of the body. halo, which we see as an arch in the sky from the curtain-like band, closing in, so Prof. Birkeland then supposes that such from most ordinary view points, attainable as to form a bowl or halo. It is practical- corpuscles are "sucked" into the earth's by the average observer. ly impossible to artificially produce or de- magnetic poles, giving rise to vortices or Figs. 1 and 2 show this arch effect that scribe in words the truly magnificent whirlpools of electric current in the upper some travelers in Northern regions have effect thus attained by nature's handiwork strata of the atmosphere. As is well known, had the good fortune to see. These cur- and which probably will never be dupli- such rays can, of course, be deflected by a tains of fire forming the Aurora rise up- cated by man artificially, or at least never magnet. Also the presence of large solar ward and in the course of a short space on any such grand scale, as occurs in the or "sun spots" is invariably accompanied of time they would close in so as to form Northermost regions of the earth, which by powerful magnetic storms on the earth, a parabola or bowl formation. Also it was few, indeed, ever visit." as they are termed, and which often cause noted that the axial- 'cénter of this bowl The illustrations at Figs. 1 and 2 give trouble on telegraph and other circuits formation was the magnetic pole of the

www.americanradiohistory.com October, 1915 THE ELECTRICAL EXPERIMENTER 245 earth. A number of mathematical calcula- Wireless and Telephone Find Extensive Use in European Armies tions were made in order to check this, as well as the usual observations as taken by Wireless telegraphy, as well as wire tel- is surprising how quickly communication regular explorer's instruments. egraphy and telephony, has found very by telegraph, telephone or radio can be Prof. Paulsen classes the Aurorae into extended application in the vast armies established between widely extended points Neu divisions. Those considered in the now battling over the face of Europe. of a mobile army. The telegraph and tele- "first class" are those which are widely extended in their formation and also quite steady. They show no streamers worth mentioning. Generally speaking, they tend to rise slowly toward the zenith, and they do not affect the magnetic or compass needle appreciably. An Aurora of this type usually appears in the form of an arch or a multitude of arches. Extended regions of the Arctic and Antarctic skies often glow with a faint light, like translucent clouds. ' These luminous masses are very often observed 1,000 feet above the ground. In the "second class" in the category of Aurorae may be mentioned those charac- terized by streamers or very distinct rays, which may be either sharply separated or they may blend at the bottom, presenting the appearance of mighty curtains, flapping gently, now rapidly, in the breeze. It has been noted that these rays are In- variably parallel with the magnetic or compass needle and when viewed perspec- tively, they appear to diverge from the center of a radially striped corona. Auro- rae of this class are not steady, but are traversed by a series of waves, as they rise from the Northern horizon and also they deflect the compass needle to the east, but after passing the zenith they cause a west- ward deviation of same. From these ob- servations, Prof. Paulsen is inclined to be- lieve that these streamers are only rays in Photos by Paul Thompson. which negative electric charges move Above: Modern Wireless "Cart" Set in Use downward toward the earth itself. by British Army In the Present As our illustrations indicate, the Aurora Terrific European Conflict. Borealis does not start from the very edge Below: German "Telephone" Station in Use of the horizon proper, but it begins at a at Advanced Posts in France. considerable distance above the earth. The altitude of the base of the arches formed phone are by the Aurora ribbon, if we may so call wires usually, in this case, le, out from a reel carried on it, has been measured in various ways a horseback, the horse number of times by explorers and others also carrying a signal corps engineer. goes making a study of the subject. From vari- It without saying that if it were not ous calculations by means of trigonometry for the rapid and far -reaching means of and geometry and also by measurements communication now available, thanks to made direct with surveying instruments, electricity, the rapid movement of troops could the average altitude of the arch above the rever be attempted with the success earth's surface has been found to vary :tow attending such manoeuvres under from 20 to 100 miles. Perhaps the highest actual battle conditions, as demonstrated altitudes that have been deduced, says ime and again by the Germans as well as Alfred Angot, in his excellent work on the by the Allies' forces. subject are the following: as measured by Our first photograph shows a modern Dalton, 150 miles; Loomis, 400 to 600 EXPORTERS wireless as ARE TOLD TO USE miles; Bergman, 468 miles; Boskovitch, "cart" set used in the British army. These sets are and WIRELESS. 320; Fournerin, 1,006; Twining, 1,100 very compact can be The American State Department, through miles; Boller, 1.243 miles. unpacked and set up, ready for op- eration in transmitting radiograms over the Atlanta Chamber of Commerce, re- The upper altitude of these arches, of sections of several hundred miles, in a few cently notified Southern exporters to course, is naturally considerably higher, minutes' time. handle their foreign communications by depending upon the magnitude of the par- An oil or a gasoline engine is usually em- wireless telegraphy to avoid the strict cen- ticular Aurora observed. ployed to drive an alternating- current gen- sorship which the belligerent nations have Regarding the periodicity of the Aurora erator, and the transformers in the radio maintained on all cablegrams from the Borealis it may be said that for one thing transmitting set are thus supplied with United States since the outbreak of the it occurs as intimated previously, with current. These sets, as here shown, are war. every recurrence of large sun spots. Final- usually rated at 1 to 2 kw. and utilize a This information was sent from Wash- ly and in spite of its apparent irregular- collapsible steel or wooden mast having a ington by Second Assistant Secretary of ity, the Aurora Borealis seems to follow a total height of 80 to 90 feet. State Alvey A. Adee, following a protest well -established routine as to its occur- The second illustration shows the field from the chamber recently that a number rence and recurrence. The periods fairly "wire" telephone apparatus in actual use by of Atlanta exporting houses had been un- well established for its appearance may be the signal corps of the German army. This able to communicate with their foreign sunimed up as follows: particular photograph was taken at one of agents on commercial matters by cable- The diurnal period, the annual period the outlying advance posts of the German gram. and the period of a little more than 11 army near the Aisne. These telephone sta- It has been advised by the State Depart- years. Among the occurrence periods not tions are indicated by a large letter "T" ment that the Postal Telegraph lines be exactly known, but of which the existence hung on the tree, as perceived. This is used when wireless messages are sent via seems to be proven, there is one of about for the guidance only, of course, of mem- the Sayville radio station, and that the 28 to 30 days and another of about 551/2 bers of the local regiment to which the in- Western Union wires be used in the trans- years. Other occurrence periods have been struments belong. mission of air messages from the Tucker - surmised and mentioned by different As may be seen, the apparatus is quite ton radio station. authorities and investigators, especially a heavy in its make -up, and it is extremely period of about 220 years, but they seem necessary that such apparatus shall be rather doubtful. very rugged, so as to withstand the severe We want to buy May. '13, Oct, '13, and Jan., (Continued on page 300.) wear and tear of military requirements. It '14, copies "E. E." Address the Editor.

www.americanradiohistory.com 246 THE ELECTRICAL EXPERIMENTER October, 1915 Baron Münchhausen's'New Scientific Adventures By Hugo Gernsback

Münchhausen Departs for the Planet Mars ONCE upon a time a grouchy old vivid as well as prophetic mind conceived sonorous voice to -night had an unfamiliar gentleman with a grievance for it, down to the most minute detail, emerges metallic timbre that puzzled me greatly; fiction writers, presumably because from a German harbor and travels under in a short time, however, the mystery was the latter received more emoluments for its own power over a distance of 4,000 miles, cleared, and this. is what poured in my their stuff than the former for his poetry, through the North Sea, the English Chan- astonished ears : thus vented his resentment in immortal song: nel, down the Atlantic, through the entire "My dear A,ier. No doubt you thought "'Tin strange, but true; for truth is al- length of the Mediterranean and up I had been killed by a meteor last night. ways strange -stranger than fiction." through the Dardanelles to Constantinople! Well, as you Americans put it, I had indeed From this some coarse soul, totally ob- And by way of diversion it manages to 'a close shave.' A meteor crashed down on livious of any poetic infection whatsoever, sink several battleships of the enemy by my aerial 50 feet from where I was sit- took it upon himself to mutilate the above means of its torpedoes. Now, bold as he ting ; it of course went up in smoke -metal passage of one of Lord Byron's poems was, Jules Verne never conceived such an vapor, to be correct -due to the tremendous and taught us. unsuspecting- mortals to "impossible thing," and while his famous heat generated by the impact of the meteor hawk, parrot -wise, ever after until the end Nautilus was equipped with almost every on the granite rocks. The whole meteor of fiction, thusly : "Truth is stranger than other modern submarine necessity, the in- itself went up in a fiery cloud of red vapor fiction I" fernal automobile- torpedo was missing. and I was blown headlong a distance of With all due regard to the memory and Truth is indeed very much stranger than over 50 feet, right down into the mouth genius of Byron, I, I. M. Alier, a citizen fiction. Hundreds of similar instances of a giant crater, by the colossal resulting of a free country, take it upon myself to could be cited, but lack of space prohibits blast of the concussion. correct his Lordship at this late and quar- it ; besides, I mustn't ramble!* "Now, this long- extinct crater is a very relsome date, to wit : Münchhausen, as will be remembered, deep one ; how deep I was soon to learn l I "There is ,io fiction." had explained the mysteries of the moon went down head first and kept on falling at a If, as often - no, always - has been to me, and he had also mentioned the great terrible rate of speed. I must have been fall- proved that the most violent fiction at some danger of falling meteors, which had been ing down that awful abyss what seemed to time or other invariably comes true, then increasing alarmingly in number for some me like hours. As I kept on plunging down I by all proceeds of modern logic, there time. tThe moon's attenuated atmosphere was gloomily reflecting what an inglorious cannot be such a thing as fiction. It simply offered no protection from meteors, as did death it was to die down at the bottom of does not exist. This brings us face to face the earth's thick air. But few meteors ever an unromantic crater on a dead and dried - with the startling result that if fiction reach the surface of the earth; the colossal up moon. I thought of many things, when always comes true some time or other, why friction between the meteor and the air I suddenly became conscious of a terrific then, bless their dear souls, all fiction ignites the former and most of it falls cold. Call it instinct or presence of mind, writers must be prophets!! Hurrah for down on the earth as a fine dust. The as soon as I had started on my downward the F. W. t ! But hold on, boys ; don't let burning of the meteors represents the journey I had jerked my body in such a our enthusiasm run away with us on a shooting stars we see. On the moon, how- manner as to righten it ; in other words, Ford. The spark plug has run afoul ever, the meteors crash down bodily, caus- after a few attempts I succeeded in falling somewhere. While it's nice to be a prophet, ing tremendous havoc, and this terrible feet down. It was indeed a fortunate cir- don't you forget that a prophet is never, bombardment goes on forever, without let - cumstance that the sun was almost directly never recognized in his own country. Thus up.t Consequently, when Baron Münch- overhead the crater, for it saved me the the New Testament teaches; so I think it hausen stopped short that evening in the anguish of plunging down into a pitch - will be safer for all F. W. to remain F. W., midst of a sentence. I naturally was black abyss. While it was of course not rather than to be honorless prophets. alarmed not a little. Great, therefore; was as light as at the top, still I could' see However, that is not what I had in mind my joy when, sitting before my radio set where I was falling, and that was at least when I started -it's so hard for me to say the next evening, 'phones clapped tight some consolation. Thus, when I glanced what I mean, and a good deal harder for over my ears, my eyes glued on the clock, down in the direction of my feet after a me to keep my thoughts running on the the familiar high, whining spark suddenly while, I am sure that my heart, which had track. They ramble from one nothingness reverberated in my ears at the stroke of stopped beating, stood still entirely for into another. My mind in that respect is 11 o'clock. some seconds. It took me a few seconds a good deal like a one -eyed, religious old It was Münchhausen. But his usual to collect my bewildered senses, for this is cow on a pasture. She what I had seen: eats up whatever s h e "The crater had no sees alongside of her, bottom at all, but went but when she finally t4 HERE are more things in heaven and earth, Ho- right through to the turns around she per- ratio, than are dreamt of in your philosophy." center of the moon, ceives with astonishment where it connected with that there is still a So sings Shakespeare. One of these "things in heaven" is the another crater, which whole lot to graze on the Planet Mars, the most fascinating, the most astounding revelation to the went to the opposite side other side; so she steers feeble human intelligence. Shakespeare, the master of the drama, never of the moon. I knew around to starboard and conceived anything like a drama of an entire world-millions of intelli- this must be so because returns to her original when I had looked down starting point. gent beings- fighting a heroic battle, a battle for existence. Yet this I had seen several stars But I am rambling drama was going on right before his very eyes, but 35 million miles shining through bril- again. So let's return away; for the Martians have been fighting for water ages ago, and the liantly from the night to the original starting side of the moon. Then point. available supply becomes smaller each year. the awful truth flashed Seriously speaking, and There is nothing more inspilina, nothing more gripping to the imagi- through me and I almost by way of emphasizing nation, than t!-is wonderful battle between organized intelligence on one swooned. I was falling how much stranger truth side and unrelenting nature on the other. through the whole length is than fiction, I have of the moon! I had but to point to Jules Mr. Münchhausen's scientific lecture gives you the latest facts -now been in many tight quar- Verne's famous stories. almost universally believed-about Mars. You can spend no better half ters before during my When 45 years ago he hour than turning your mind from your humdrum existence towards a somewhat exciting career, but this experi- wrote "Twenty Thou- which is as as is lofty in its sand Leagues Under the subject absorbing it grandeur. ence indeed bade well to Sea" no one took him be the inglorious end of serious. It is doubtful my adventurous I i f e. whether he himself be- However, my far -famed lieved that the submarine which he invented presence of mind and my cool head soon become practical. In order to distinguish facts from fiction in asserted themselves, as was naturally to be in that story would ever this instalment, all statements containing actual It was just fiction. Ye: 45 years later we scientific facts will be enclosed between two t expected of me. see how a submarine, almost exactly as his marks.-.AUTHOR. "I knew the diameter of the moon to be

www.americanradiohistory.com October, 1915 THE ELECTRICAL EXPERIMENTER 2E7

Four different views of the planet Mars. As Mars turns on its axis are turned upside down. The white patch at the bottom is the north l'ola once every 24 hours the same as the earth, we are enahled to see the entire snow cap, the southern cap is not in evidence for it has melted already. The surface of the Martian globe during that time. The four views, as shown, melted water has been conducted equatorward by the "canals." Note that the are therefore taken six hours apart from each other. These pictures were canals run through the dark areas, which are not oceans therefore, but land made during the last "opposition" in 1911, when Mars was some 47 million miles with vegetation. The light areas are deserts. Nearly all canals are per- distant from the earth. It never comes nearer than 35 million miles to the fectly straight, the ones near the edges of the pictures, appear curved only be- earth. In 1924 the two planets will be hut 35 million miles apart. In toe views cause we are looking on a glohe and not on a plane surface. shown the top is south, the bottom north, for through the telescope all objects i hotos courtesy of Prof. Percival Lowell, Flagstaff Ohservatory, Flagstaff, Ariz. 2,164 miles. A quick mental calculation "I say almost, for the friction of my trial time, when the meteor smashed my proved that it would take my falling body body against the air would tend to retard aerial; this, then, was the time I started on about 24 minutes to reach the center of the my fall. If at this point, where my speed my remarkable journey into the bowels of moon. As there was nothing to stop my was again zero, I could not succeed in the moon. With a tremendous effort I fall, I must naturally continue to fall, due taking hold of a projecting rock of the pulled out my chronometer and noted that to the tremendous momentum acquired, till crater's side I would begin to fall down it was 12.23 a. IL In another minute I my body would alrnvst emerge at tic. oppo- one m.>rt, the same as before. I would would fly past the. center of the moon. site side of the moon at the mouth of the then continue falling back and forward ex- Looking abour., I saw in the uncertain other crater. At th ;s point my speed would actly like a bouncing ball. each time. how- light that I went whizzing through an im- be zero and I would have fallen for 48 min- ever -just like a rubber ball -a little less mense hollow, proving to me that the utes. If I could not manage then to grasp than on the previous plunge. Thus my center of the moon was far from solid, due a projecting rock I would commence to fall drops would become of shorter and shorter no doubt to the centrifugal force of the back again toward the center of the moon. duration, and finally I would fall no moon at the time when it had not solidified. I reasoned that once more my momentum snore. some millions of years ago. I estimated would carry me past the center and I "As I had mentioned before, the sun was later that the moon was an immense hollow would then be almost carried to the mouth almost overhead, shining down into the sphere with a solid crust about 500 miles of the opposite crater-my original starting crater. I also remembered that it was al- thick. By way of a homely comparison, point. most exactly 12 o'clock midnight, terres- the moon therefore must be a hollow globe

www.americanradiohistory.com 248 THE ELECTRICAL EXPERIMENTER October, 1915 like a rubber ball. Like the latter, it is that the earth rotates on its axis from west whatever to lose, but everything to gain. filled inside with air, while its crust can to east at a speed of 1,524 feet per second "My first experience was repeated with- be compared to the rubber of the ball. at the equator. Thus it is apparent that out any incident; furthermore, I calculated "In another minute I had passed the cen- the earth revolves quicker than the stone that I should land at the eastern wall of ter and was now dropping toward the other can fall in a few seconds.* It therefore the far crater within 48 minutes if every- side of the moon. If I continued falling intercepts the stone's flight, with the result thing ran smoothly. But I had left our in my present position I must naturally that the stone must of necessity strike the good old sun out of my calculations. You emerge at the opposite side with my feet eastern wall of the shaft. This phenom- see, the gravitational attraction of the sun toward the sky, as a little reflection will enon is termed 'the falling of a body controlled the fall of my body in the same reveal to you. So once more I jerked my toward east.'t proportion as it controls the rotation of body about, and I was now falling 'up,' "Now, precisely the same condition ex- the moon and the earth, as well as the with my head at the top, my feet pointing ists on the moon, of course. Fortunately, other planets. I mentioned how in my to the sun. At the end of another 24 min- I started falling at the western side of the former flight I had risen to the top of the sites I could feel my body slowing up from crater, but as the latter was so wide I moon ; as a matter of fact, somewhat the terrific speed. As the crater at this never carne near enough to its eastern wall higher, for the opening of this crater was side of the moon was fortunately rather to hit it. Likewise the other crater, at the higher than the surface of the moon. But narrow, I found little difficulty in reaching opposite side of the moon, measured some now I was falling toward the sun, and the for a projecting rock as soon as my plunge four miles in diameter and, while I finally sun was aiding as well as accelerating my had come to a dead stop. I held on for did reach the eastern wall, my flight had flight; for I moved constantly neater to it. dear life and clambered up a narrow ledge. come to an end as explained already. In- "For this reason at the end of 48 min- where I fell down exhausted and panting deed, nature favored me all through, for utes I did not strike the eastern end of the from my dreadful experience. the moon rotates with a velocity of but crater. Instead I whizzed right past the "My sensations in falling through 2,164 15% feet per second at its equator, against eastern wall, almost brushing it, and con- miles of space, going over 16 miles per a like speed of 1,524 feet of the earth. For tinued to rise up into the air about 100 second at the center of the moon, you this reason there was no danger that my feet before my speed was spent. I would, of course, like to know. Well, the body would collide with the sides of the promptly prepared myself to plunge down first minute it is rather unpleasant. Highly crater somewhere in the interior of the into the crater again. Indeed, before I so. The place where your stomach should moon, for my flight was far more rapid realized it I had begun to fall down once be by right is one vast area of nausea. than the speed of the moon's rotation on more when the unexpected happened. But once you become accustomed to it it its axis. "I suddenly felt a rope encircling my becomes bearable, for there is nothing else "But in the meanwhile my troubles were body, and before I had time to think I was to do. You might think that the rush of far from being terminated. No sooner had jerked sideways, and in another second I air would kill you in a few seconds, or I regained my breath than I became con - had fallen on a heap of sand and looked else draw all the air out of your lungs, thus scions of the terrible cold; for I was now with astonishment into Professor Flitter - asphyxiating you. Neither is the case, for but a few feet from the surface of the nix's eyes. who stood over me grinning the air is so thin on the moon that the moon, but on that side which was turned sheepishly! rush is not so terrific as it would be on away from the sun, where nothing but icy "This is what happened: Flitternix had, earth. Also, by keeping the mouth tightly cold, darkness and desolation reign. Aside of course, seen me fall into the crater, and shut and breathing -with difficulty, it is from this, I was some 7_,160 miles away as he had rushed to the edge he had seen true, through the nose -one does not die in from Flitternix, my companion, and our how I dropped down at lightning speed. 48 minutes. The friction of the air against 'Interstellar.' Walking around half of the Looking closer, he also noticed what I saw, my body did not ignite the latter either, moon was out of the question; neither namely, that the crater went right through with a consequent burning of my dear self. could I stay where I was without freezing the entire diameter of the moon, for he For, as I told you some time ago, the tem- to death. So I climbed up to the surface could see the stars shining through from perature inside of the moon is near the of the moon with considerable effort. Then the other end. He was loath to believe absolute zero, the awful cold of the stellar by aid of the starlight I ran rapidly around that the fall would kill me, and as a world. But neither did I freeze to death, to the western side of the crater, for I had scientist of note, he calculated exactly in for the simple reason that the friction of to run in order to keep warm. After hav- advance what was likely to happen to me. my body through the attenuated air was ing obtained my bearings by aid of the He reflected that it would take me some just sufficient to heat me up enough so as stellar constellations, to make sure that I two hours to make the round trip, as he to keep me comfortable. Thus you see was at the western side of the crater, I took knew that I could not possibly stay at the that if it had not been so cold 1 would a deep breath, looked down in the abyss other side of the moon. He reasoned, cor- have burned up; and vice versa, if the through which the sum was shining from rectly, that in case I was not killed I would frictio n of the air against my come swinging through the body had not heated it, I would crater in due time. Unperturbed have frozen to death long be- as he is by such mere details, fore reaching the center of the he went to the 'Interstellar' and moon. Then, top, another im- had his lunch. Within two portant point to consider is that hours he returned to the crater, on the moon, as explained previ- armed with a telescope and a ously, my body weighed but 27 long rope. It did not take him pounds, against 170 pounds on long to locate me down in the earth.* This is, of course, a abyss by means of his glass, for rather small weight, and for that I was rapidly coming to the sur- reason my fall was not so ter- face then. Attaching one end rible as if my body had weighed of the rope to a near -by rock, 170 pounds, as on earth. For he fashioned a sliding noose on that reason, too, I was not at- the other side and waited. tracted so much to the sides of "Now it must be said to the the crater as I would have been credit of Flitternix that in his if my weight had been greater. younger days he had lived in Also it was fortunate that the the West on a ranch, and there two craters widened out consid- had become an expert in the erably the further down they science of lassoing. He boasted went into, the moon's interior. Vegetation increasiny North that once he lassoed a common As a matter of fact, the 'hole' and decreasing [South, sparrow by its left hind leg. of each crater at no point was but this I believe to be some - less than three miles in diameter. Photo by Lowell Obse rvatory. what exaggerated. Be that as This was indeed very lucky for me, for the other side, and dived head down into it may, when I finally emerged to the the following reason: space once more. surface, a living piece of lava ejected t "If we drop a stone in a very deep and "You see, I had reasoned that it was far out of an extinct crater, Flitternix had but narrow shaft, as has been shown experi- better to attempt the flying journey through little trouble in lassoing me as I came mentally on earth, this stone will never the moon once more than to perish with whizzing un. Whereupon I thanked him and reach the bottom. Instead, it will bury the cold on the dark side of the moon. Be- asked him if lunch was ready, for the trip itself into the eastern wall of the shaft sides, I had experience now and, having had given me quite an appetite, as you may long before reaching bottom, providing the been successful once, it was natural for me well imagine. Luncheon over, we decided shaft is deep enough. The explanation is to expect success again. I had nothing right then and there to quit the moon, for Flitternix as well as myself were [The speed of a falling body at the surface of of the tAn object weighing 1 Ib. on Earth weighs the earth after the first second is 16 1.12 feet. In opinion that there was little further to be 0.167 1b. on the 111oon.t 6 seconds a stone would have traveled but 579.E (Continued on page 297.)

www.americanradiohistory.com October. 19 t 5 THE ELECTRICAL EXPERIMENTER 249 The Gravitation Nullifier Ned Cawthorne, Millionaire, "Floats" a New Issue, but Not of Bonds By George Frederic Stratton THE gigantic mogul, No. 73, had been But he found nothing wrong. The rails him and wafted him along as though he held on a siding on the Santa Fe were dry and in perfect condition; and was thistle down. Fifty yards away he Railroad waiting for three troop with a lowering puzzled look he climbed drifted against the telegraph wires and trains to pass on their rush to the Rio back into the cab, threw over the revers- clung to them convulsively. Grouped be- Grande. Behind her were 40 empties ing lever and opened the throttle. There tween him and the engine were the train which she was hauling back to be re- was not the slightest impulse backward or crew and station helpers, staring in be- loaded with munitions and supplies and forward. wildered terror, and a few yards behind again to be rushed to the front. The sharp exhaust cut out the explosion them stood a man, dressed in gray, wav- Blakely, the engineer, who had been 19 of picturesque idiom and expletive from ing what looked like a pocket searchlight, hours on the run and saw no relief un'il Blakely. Then he yelled to the conductor in signals to a biplane, far overhead. he reached Los Lunas, was doggedly who had come forward: "Cut her loose, A cavalry lieutenant with a squad of morose, for his orders were coming fron Hank !" troops galloped round the station and

. . . Thousands of Men Were Wriggling in the Air, Mixed Up with Machine Guns, Mortars and Small Arms." dapper second lieutenants or curt, brusque The mogul was uncoupled and again the down the track, halting as they reached majors, instead of through smiling station engineer gave her steam and his puzzle be- the man in gray. agents with their crisp telegrams. At last came a miracle. The great locomotive "What does this mean, sir? What aero- he got his signal and viciously pulled his started forward with a plunge which threw plane is that, and why are you signaling? throttle. There was a furious rush and the fireman back on the coal; the for- Who are you ?" whir of the 12- coupled drivers but no ward trucks sprang clear of the rails and "My name is Cawthorne," smiled the headway. a sharp gust of wind sweeping down the other. "I'm interested in a new device He instinctively shut off steam, turned arroya lifted the huge machine into the air for suspending gravitation, and that bi- on the sand and again slowly and cau- and floated it across the main track. Then plane is operating it." He turned to the tiously opened the throttle with the same it settled down in the sagebrush so gently fireman in the wires and shouted: "Drop result -a whirl of the drivers as if they as not to displace one chunk of coal. off at the first lull of the wind. You'll were the wheels of a child's wagon, spin- Blakely slumped back on his seat, aghast, settle down, all right." ning in the air. and the tan on his corrugated cheeks and The lieutenant spurred close to him. "I "Grease ?" grunted the fireman. forehead faded off to a sickly ashen gray. suppo.3e you know that the road is under "There'll be a grease -spot if I catch any The fireman sprang from the cab, his hair martial law and that you're interfering blamed fools playin' tricks 'round here!" standing on end. but instead of his feet with its operation. You're under arrest, howled Blakely as he sprang from the cab. reaching the ground the breeze caught sir!"

www.americanradiohistory.com 250 THE ELECTRICAL EXPERIMENTER October, 1915

"Certainly," grinned Cawthorne. "Now, antennae and the gravitation- suppression been my greatest ambition to hold a com- perhaps you'll allow me to put that loco- instantly occurred." mission in this war, general; but I have motive again into commission." "Good heavens!" ejaculated the general. a cork leg-lost the other at polo. Does He stepped over to the great engine, "It's beyond the realms of possibility, Mr that disqualify me ?" followed by the officer and his squad, and Cawthorne !" "Perhaps," smiled the general. "But the placing one hand under the cowcatcher "Edison says that the limits of the possi- aviation service is hardly down to fine re- lifted the entire front of the locomotive bilities of science are not yet in sight. strictions, yet. We'll overlook the cork. clear of the sagebrush. What we have done seems impossible be- What men do you carry in that aero- "Gravity entirely gone 1" he laughed. cause it has never been demonstrated. But, plane ?" "Call on two or three of those men to your officer has seen, and has reported to "Two. Kilroth, one of the brainiest help and we'll put this back on the track you about the possibility." mechanics I ever knew, and Littleby, the in a moment. Then we'll restore its weight "And the influence -or whatever it is- -er- chauffeur, but there's room for two and it can go ahead." extends only to the radius covered by those others." The officer scowled and hesitated. Then balls ?" broke in the captain. The general nodded exultantly. "Cap- he ordered four troopers to dismount and "Much further than that, captain. On tain Berger, you are detailed to accom- help. Two minutes later they had carried exhaustive experiments at my country pany Mr. -er- Captain Cawthorne. Your it over to the head of the train. As they home, conducted very secretly, we found rank, as an artillery officer, is above his, did so, Cawthorne again signaled the bi- that the influence-that's a good term-ex- but you will act together. Now, I am plane. Then he stepped to the cowcatcher tends for fully half a mile on each side going to call a council of war which you and heaved on it. of any cluster of balls; although the in- will both attend. We will then decide on "Weight's all back, lieutenant! Now tensity of the action is at its fullest among your future movements." I'm at your service." those balls. The suppression of gravita- "And in the meantime," laughed Caw- Two hours afterwards Cawthorne, es- tion becomes less as the distance in- thorne, "where am I to report? I am corted by the cavalry squad, arrived at the creases." under arrest, you know." headquarters of the Fifth Brigade and was "And yet the altitude of your gyroplane Another laugh broke from the general. immediately taken before General Illing- makes no difference ?" demanded the gen- "You are on parole now, captain. Orderly! ton. That. grizzly old warrior scrutinized eral. Report at the guard house that Mr. Kil- him keenly ; then growled: "We have worked up to 6,000 feet with- roth and the pilot of that gyroplane are to "You are Mr. Cawthorne- Edward Caw- out finding any difference in the conditions be immediately released!" thorne, I am informed." or results." As the orderly left, Cawthorne saluted Ned bowed. The general smiled grimly The captain settled back in his chair and and said: and continued: gazed at Cawthorne in blank astonishment, "There are on the track at Denver three "The man who devised those submarines his arms hanging limply on each side of sealed freight cars consigned to me. They that have been putting the Jap dread- him. The general twisted one end of his contain three more gyroplanes and a naughts to sleep ?" gray mustache into his mouth and chewed number of gravitation nullifiers. I didn't I am the man who financed them, gen- it meditatively. Presently he growled: dare bring them any further for fear of eral. The deviser is a man named "Why have you not put the war authori- -er- arrest; but they are now under your Wheaton, of Providence." ties in touch with this, instead of daring orders, general!" "Very effective, sir; whoever did it. to come right onto. the field and make a "Good heavens! Three more of those and a scowl darkened his demonstration without even consulting machines all ready! Have them for- rugged fae, "that is no excuse for experi- me ?" warded at once, captain ! No! I'd bet- menting on our battle line. Nothing can Cawthorne leaned forward, his brows ter make the order -special run, tool We be an excuse for that, sir!" furrowed deeply and his lips pressed tightly need all the reinforcements we can sum- "It was not experiment, general; but together: mon just now l" demonstration. Shall I explain ?" "Two years ago, general, the war au- * * "I will listen to you, sir, but I warn you thorities were shown this apparatus and' Four thousand feet in the air the two that no explanation can relieve you of they shrugged their shoulders and turned captains, Cawthorne and Berger, were the consequences of your action. You de- it down. If we had gone to them now cruising over the trenches of the mixed layed that freight train for nearly ten with the perfected machine they'd have brown and yellow men. Around them minutes -a very serious matter at this red -taped it until those Japo -Chinee devils were a score of United States aeroplanes time ! Orderly! Request Captain Berger had reached Washington, and then they'd guarding the G. N. 1 against attacks by to come here." have appointed an investigation committee, Japo -Chinee airships. In a few moments the artillery captain with an unlimited period of time for the The world just below was sparkling appeared. The general muttered: investigation and tests. War authorities with angry flashes of flame preceding the "Mr. Cawthorne proposes to explain the are not field officers, general !" rattle of machine guns and the explosion method by which he floated that locomo- "That will do, sir! I can listen to no of shrapnel. The enemy had brought up tive off the tracks. Be seated, gentle- criticisms on the Government." But a no heavy guns, but from the American men!" twinkle in the stern old eyes softened the lines across the river came the terrific "Four years ago," Cawthorne related, "a harshness of his tones. crash of field siege cannon. As far as Mr. Farrow showed clearly that the law "Your gyroplane is here, I suppose you Cawthorne could see on both sides of the of gravitation is influenced by the Hertzian know ?" Rio Grande were gusts of smoke; some- waves, and that they, in turn, could be in- Cawthorne grinned: "Yes! As soon as times spasmodic; sometimes continuous fluenced by electricity. I need not take up I heard where I was to be brought I sig- clouds, for the entire line was in action. time to go into the technicalities of it all, naled Kilroth, my assistant, to sail in here Berger was watching the selenium - but experimentation, right to the limit, has and descend. I suppose he's under ar- physcho plate on which, projected by the resulted in an apparatus-a condensing rest, too ?" I -ray tube at headquarters, eight miles generator -which if so handled as to The general smiled grimly but ignored away, came their orders. Kilroth and throw an electric zone around anything the question. Cawthorne were sifting handfuls of the that has weight, will eliminate that weight, "How did you expect to follow this up, globular antennae -Kilroth called them or more properly, will nullify the gravita- Mr. Cawthorn ?" "attractors" -down onto the line of tion. That locomotive was treated from "First, by doing just what has happened trenches beneath. Suddenly Berger ex- our gyroplane nearly 5,000 feet above it!" -getting an interview with you. Next, by claimed to the pilot: The captain gasped: "Do you mean, sailing over the river and-with your per- "Turn back, Everoth! Follow the same Mr. Cawthorne, that it was done without mission- floating all of that Chinee-Japo- line! Now, Captain Cawthorne, put the any communication with the earth -that Mexican aggregation into the air. How's generator- condenser into action!" there was no receiving antennae ?" that ?" Cawthorne threw the switch and all Cawthorne grinned, slipped his hand in The general glanced at the captain, his gazed down. One aeroplane immediately his pocket and drew out a few metal balls, lips twitching. The next moment both below them was evidently deprived at once as small as buckshot. He handed a couple burst into a roar of laughter. As it sub- of its weight for its pilot lost control and to the general and the others to the cap- sided, the general's hand shot out and it darted in a complete vertical revolution tain. grasped Ned's. "We can use you, sir! and then rushed far into the south. "Those are the antennae. Simply solid We'll have to, to save ourselves. I could "Must have caught a few of our at- metal balls! I don't care to tell the com- spare 25 or 30 pounds very willingly, but tractors," grunted Kilroth. "Look below!" position, just now; but they're perfectly :ne rest of my weight I want. Beneath them was as much confusion harmless. A bushel of them was carried "But, under the regulations of war you'll as if a tremendous explosion had oc- in the gyroplane and a few handfuls have to come under my command. I'll curred. Thotisands of men were wriggling thrown down around the locomotive. appoint you a captain of aviation. Will in the air, mixed up with machine guns, Then, when the condensing generator was that do ?" mortars and small arms. Evero h had put into action the current found those Cawthorne exclaimed bitterly: "It has slowed his motors down to 20 miles an

www.americanradiohistory.com October: 1915 THE ELECTRICAL EXPERIMENTER 251

hour and in 15 minutes the generator con- Instantly a lieutenant sprang out and five hours, or less ; we could assemble a denser had passed over the five -mile line ran over to them. machine in two hours and bring it here of trenches and utterly demoralized the "We've room for your party, Captain in another five. Twelve or. 15 hours at enemy. Cawthorne. You can do nothing more the most, general!" Firing ceased instantly and as the here, I suppose," with a glance at the "Do it!" exclaimed the general. "I'll smoke swept away the fighters in the smashed gyroplane. order those cars sidetracked at- er -Cap- G.N.1 had a clear view as they turned and Cawthorne looked at Berger, who tain Berger, find out what station that again sailed over the line. For a half mile nodded, and then said: train will reach five hours hence, and dis- ahead and behind them and to each side "One of our men is injured. Is it pos- patch orders to drop those three cars the enemy and its equipment were in the sible to carry him out of this ?" there!" Then turning to Cawthorne: air, and as a stiff breeze was blowing into "Here's another aero coming," replied "The enemy has heavy reinforcements the north, thousands of those brown and the lieutenant. "Hi! What's this mean!" coming up, within a hundred and fifty yellow men and thousands of small arms A. hundred rods to one side a number miles of the river; and you'd be back in and big guns were drifting like feathers of armed Japs were rushing towards time to meet them. Take all the men you towards the river. them. Cawthorne's party drew close to- need and return with the first machine you As the gyroplane passed along and its gether, revolvers in hand. can get together!" zone of influence left those aerial enemies, "Hold your fire 'til they're within a Then he turned with a chuckling grin to their weight came back as suddenly as it hundred feet!" commanded Berger, but Kilroth. had been nullified, and they dropped onto the next moment Kilroth gave a fearful "You, my nullifier impersonator, can, I the plain or into the river. Firing from shriek, sprang four feet in the air, his suppose, assemble the other machines and the American side had ceased and Berger arms waving wildly, and as he came bring :hem to the front without delay ?" yelled: down, he clutched at the wheel of a gun Kilroth grinned and bowed. Ten min- "Look Cawthorne I Our men are rush - and clung to it, still howling. utes later the party, with four skilled me- ing down the pontoons. They'll have a The effect on the Japs was instan- chanics, were sailing north. bridge across in an hour! Ml we've got taneous and astoundingly effective. Every- * * * to do is to keep these fellows floating and one of them was groveling on his belly, Coming northeast from Guaymas Bay, dropping until our troops get across!" clutching at brush, at rocks, at the hair in the Gulf of California, was the main They glided down within 200 feet of or arms of his fellows, at anything for army of the Japo -Chinee-Mexican alli- the surface. The enemy's aeroplanes had an anchorage to his dear old Mother ance. Almost in sight of each other train darted away, for as they came within the Earth. sections were crawling along the railroad, influence of the nullifier their control be- Kilroth doubled up in a paroxism of bringing up heavy field guns, aeroplanes, came alarmingly erratic. munitions, supplies and The American airships, men. On the trails and previously warned, were plains mounted Mexicans prepared a n d followed YOU have read, of course, Mr. Stratton's interesting story "Omegon," of Cabellero's and the enemy in fierce at- Here's This story is as startling Valejo's commands were tack. last month. the continuation: advancing, devastating Suddenly there was a as it is original; moreover it is exceedingly timely and it may every ranch, village and shrill yell from the pilot, sound far more impossible than it really is, for Professor Thomas Jefferson town on the 10 -mile a dark shadow and a Jackson See, of the Naval Observatory at Mare Island, Cal., has just an- wide trail. crash. of the One enemy's nounced one of the most important and momentous discoveries of the age. The head of this army biplanes, recklessly had reached Guadeloupe, driven or out of control, He claims that gravity is but another electrical phenomenon caused by 40 miles from the Rio had rushed into the path electrical currents circulating about atoms of matter. If this is really Grande, and had en- of the G.N.1. There was we have no reason to doubt the new theory-then Mr. Stratton's camped there waiting no weight so-and to, either of probable, possible. for more forces to come the fliers, but the initial story is not only but highly up; but when the amaz- strength of structure was You must read this tale by all means. ing news arrived of the there, and the speed, and mysterious disaster at in a- moment -the nulli the front, they were fier being crumpled out again put on the of action -both planes were toppling to the laughter, the contagion of which spread march. Presently fugitives from the river ground. All but Everoth, who came down to the others. straggled in, amazing and terrifying the on rocks and broke boxh legs, landed in one "Pick up that wounded man!" shouted new men with stories of their flotations. of the trenches on top of a party of quiver- a voice, and they lifted him into the A great group of aeroplanes appeared. ing Japs who had crawled back there after frame of the second aeroplane. Another three or four thousand feet above, for ex- the first attack of the mysterious influ- instant they were all again in the air, sail- cepting a few held back for scouting pur- ence. But for the fact that in their aerial ing at full speed towards headquarters, poses, every airship in Illington's division flutterings their rifles and even their re- while the Japanese officer was leaping was escorting the G.N.2. Hovering about volvers had wafted away from them, Caw- among his prostrate men, striking them them at respectful distances were a few thorne and his party would have met in- with the flat of his sword and using lan- of the Japo -Chinee airships, and occasional stant death. But they scrambled out and guage which was perhaps appealing elo- flashes from guns showed spasmodic at- drawing their own revolvers, clustered quence, but was certainly decorated with an tempts at interference. about the wrecked gyroplane. unlimited assortment of profane trimmings. Presently there dropped on the advanc- Captain Berger glanced around him. "Marvelous! marvelous!" muttered Gen- ing troops small pellets metal eral of which, On every side sprawled men, clutching Illington as he heard their report. coming from so great a height, caused rocks, sagebrush, each other or parts of "Two hundred thousand of the enemy severe wounds on the few men they hap - field guns; anything which, in their ab- routed, and not one of your men lost I" pened to hit. Then one gyroplane-the G. ject terror, might keep the weird, mys- "One man injured I" grinned Caw - N 2- darted below the others and glided terious unknown from fluttering them thorne, "and we brought him out." directly over the column of troops be- again off their feet. of them were "The loss of the gyroplane is serious," neath. dead from plunge from great heights muttered the general. `The enemy may when Again were the astounding conditions their weight was restored. Many rally before we get our bridge across; it and demoralization at the Rio Grande re- others were crippled in limbs or ribs. will take fully an hour, yet; even if the Others peated ; but as there was not the slightest were crushed under machine guns engineers are not attacked by shell." breeze the effects were not quite so evident or howitzers which had dropped on them. Captain saluted: "I think, general, that Down to Cawthorne's party. Men lifting their at the extreme right of the Line- there isn't a gun over there in condition feet to the march step were unable to re- a position which had been held by Cabel- to go into action without repairs or ad- lero's place them with any accuracy and would t! Mexicans- Berger saw a large body justments." stagger or drift against each other in utter of them rushing in frantic disorder back "Have the other gyroplanes left Denver helplessness. Horses hauling heavy guns across the great plain to timber far in yet ?" asked Cawthorne. and baggage wagons suddenly plunged the rear. At another point nearer to him The general growled: "A report came was ahead as all weight behind vanished and a Jap officer gesticulating to his men in just before you arrived that the train then reared in in an effort to reorganize and sought vain for secure them, but not a had reached Valencio. But it adds that , man footing. In an instant, as the gyroplane but himself was standing up. the line is terribly congested and that the glided slowly over them, all order, all dis- "Here's a rescue, Berger!" shouted train cannot reach here for 40 or 50 hours cipline and all courage disappeared. Men Cawthorne, as a big aeroplane glided to -perhaps longer !" fluttered along the sometimes the ground close ground- by, and he saw the khaki "Valencio !" muttered Cawthorne, "that's head down, sometimes half a dozen clutch - uniforms. 400 miles. An aeroólane could make it in (Continued on page 300.)

www.americanradiohistory.com 252 THE ELECTRICAL EXPERIMENTER October, 1915 Conserving Uncle George By Thomas Reed YOU know that gentleman by the name wise, I've been there. We want pa and the you can pick up any time and say with of Sloyd? He was the apostle of neighbors to exclaim respectfully, "Gee, tears of gratitude in your eyes, "Uncle Care and Pains. If you are making ain't it great? what's it for ?" instead of George gave me that." a joint, he says fuss over it as though all smiling scornfully as they recognize the Well, humor him -that's the way we old the joiners of Joinville were watching you gate- hinge, the dry- battery carbon and the fellows get to be so awful rich. Pretty with their eyes bulging out. And don't shaving -stick box. soon Uncle George will begin testing out you dare to fudge it up. In the chronic state of a boy's exchequer the ground in the guise of advance agent The article you are making is not so it's a tough choice between tools and ma- of S. Claus & Co., Ltd. Now don't let him, important. You simply think up some- terials, because every dollar spent for one in his ignorance, blow you to one of those thing to make that will have to have a joint means one dollar less for the other. Well, so- called tool- chests at which a pound on it. Say you decide of cheese would laugh. on a nice knife -tray What do you want of for mother. Mother a young tack -hammer, would rather have a a chalkline, plumb -bob new set of knives and and a square that isn't could keep them any square? No, sir, hand old place; but father it to him straight about missed it on Amal' a- the drill and the cen- m a t e d Shoestring ter -punch and the hack- Common and can't see saw. Head him off the knives just now. from one of those Sorry. All the same things you can imitate mother pats you on the a suspension bridge or shoulder and says what a flying- machine with. a dear, thoughtful boy If he commences to you are, and the hired talk in two figures like girl turns the tray over a sport, you can sug- and uses it to set the gest that he who garbage pail on. And passes along a good so it goes. l a t he would surely Sloyd may he all avoid the appearance of right for certain na- a piker. tures-there's room for Here's a list of tools lots of things in the you want -tools to use, world -but the Exper- not to form a museum imental Bug think: lifc with. Paste it in is too short for his Uncle George's hat or philosophy. If I con- on his eyebrow, and fess something don't W'e %t'ant Pa and the Neighbors to Exclaim Respectfully, ' Gee, Ain't It Great? you will never regret you tell Gernsback or What's It For ?'" it, though he may. I he'd fire me out of the don't include the neces- E. E. with a splash, mother's overboard; what'll we do about it? Conserve your sary hammer, saw, plane, etc., as I assume but I'd rather see an odd contraption rigged resources, I say. you have pinched father's! up out of a tomato can and three umbrella "What's that ?" say you, "conserve 'em? Hand drill, $1.25; hacksaw, 50e.; hand wires than the most perfect skewangular They're so small it's as much as I can do beading tool, $1; center punch, 10c.; metal joint in the world. to find 'em, let alone that con -con -that shears, 50c.; pliers, 25c.; iron rabbit -plane, Sloyd begins at the back end. You and phoney word you used." "Well, listen," $1 ; marking gauge, 25c.; iron vise, 3 -in. I start by wanting something and wanting says I, "part of your resources is Uncle jaw, $1.50; miter -box, $4.50; ratchet bit- it bad, and then we go to work and make George, isn't it? Don't he generally come stock, $1; countersink, 10c.; hand emery- it with what tools and materials we've got. across about Christmas time or the birth- wheel, $1.29; compass saw, 25c.; oilstone, When it's done it may look like a chance day? Sure he does. Then he's a resource 25c.; lathe, $40; bench vise screw (make grab from the damp, bitt what of that if it and you want to conserve him." your own jaws), 50c.; files, flat and half Now it's this way : Don't tap Uncle round, 25c. each ; twist drills, >'e to Yee bby works ? George for materials, but let him buy the 64ths, about $1; wood bits, 1/4, % and 1/2 Then if our crude rinktum succeeds, we tools. The little roll of that silk- covered in., 25c. each; expansion bit, 1/2 ' to 13 in., begin all over again and rebuild it in wire that you want so much wouldn't ap- 75c.; 8/32 tap and die, with die stock, worthy form-doll it up with a mahogany peal to him. It disappears and he thinks $1.50; tool handle with enclosed awl points, base and plenty of binding -posts. Even a you're extravagant, and extravagance is etc., 25 to 75c. few superfluous switches and milled nuts bad for you. What he wants to give you Hits any mark from a tightwad to a are not amiss just to give it tone. Oh I'm is something large and shiny- something joy -rider, eh, Bugs?

PROF. SEE CLAIMS TO KNOW been taken to denote the unit of electrical U. S. NAVAL RADIO SCHEMES CAUSE OF GRAVITATION. current, showed that two parallel currents PROGRESS. Dr. Howard D. 1linchin, of the Univer- of electricity flowing in the same direction The naval radio construction program of sity of Rochester, will inquire into the an- attract each other, but repel when flowing nouncement the Government has gone far enough to of Prof. Thomas Jefferson in opposite directions. warrant the statement that it is to be car- Jackson See, one of the best -known astron- The more atomic electric currents around omers and mathematic ried forward to completion without ex- :ans in the United one body of matter flowing in the same ceeding the $1,500,000 limit cost fixed by States and at present in of charge of the direction as the atomic currents in an ad- Congress. The system when in operation, Naval Observatory at Mare Island, Cal., jacent body the more the two bodies will that he has discovered the cause of it will be recalled, is to circle the globe, gravita- be attracted, Professor See contends, and giving the American at Wash- tion. Students in science are greatly inter- this mutual attraction is nothing nor Government more ington, D. C., its ested in the announcement coming from a less than gravity, direct control of battle- man of such standing. Dr. Minchin said Gravitation, Professor ships, no matter in what part of the world See contends, they may be located. he could not intelligently comment on the does not act instantly across space, but is discovery until he had investigated. transmitted with the velocity of light. The fund has been used in the construc- Professor See contends that gravitation Thus it would come from the sun to the tion and equipment of the naval radio is an electrical phenomenon which is earth in eight minutes. station on the Canal Zone, which is now caused by elementary electrical currents Professor See's treatise on his discovery in operation; and is being used for the circulating about atoms of matter. The is in the possession of the Royal Society stations at San Diego and Honolulu, where theory of Professor See is an extension of London. It was to this society that Sir work has begun ; at Cavite, where arrange- and elaboration of physical laws first dem- Isaac Newton announced his laws of gravi- ments for construction are under way, and onstrated by the French physicist, Ampere, tation in 1685. The society has not yet at Guam, where the project is in the initial 95 years ago. Ampere, whose name has passed upon the theory. stage.

www.americanradiohistory.com October. 1915 THE ELECTRICAL EXPERIMENTER 253 Can Electricity Transfer Thought Waves? WHETHER electricity can or can- with cmphasis on the "you," and when the their heads with improvised induction coils, not transfer thought waves from laughter had subsided he continued: "I but the only result of the brief first experi- one human brain to another is a have been struck by the fact that nearly all ment-revea:ed by chance two years later - much mooted question which has for some of the recent steps have had to do with was that, while there was no transmission time occupied the minds of many of the vibrations. Suppose you have the powcr to of thought, the sensation of nausea that foremost scientists in the old and new make an iron rod vibrate with any desired afflicted Ellis at the time was communi- worlds. Among some of the more well - frequency in a dark room. At first, when cated to Dr. Bell, a fact that he readily known and brilliant men who have seri- vibrating slowly, its movement will be in- recalled when, in discussing the test after ously considered this matter there may be dicated by only one sense, that of touch. the lapse of time, the professor said he did mentioned Thomas A. Edison, Sir Oliver Soon, as the vibrations increase, a low not consider it a fair trial because he had a Lodge and Prof. Alexander Graham Bell. sound will emanate from it, and it will ap- sick headache and a feeling of nausea. Dr. This whole subject revolves in a way peal to two senses. At about 32,000 vibra- Bell thinks that it may be that various sen- about the science of psychic phenomena, it tions to the second the sound will be loud sations can thus be more readily communi- may be said, and this branch of little un- and shrill, but at 40,000 vibrations it will be cated than thought, and he expects at some derstood science considers as an absolute silent, and its movement will not be in- future time to begin a more thorough ex- fact that "thoughts can be transferred from dicated by touch. Its movement will be perimentation. one mind to another," and in many cases indicated by no ordinary human sense. At Thomas A. Edison, the wizard of all in- workers in this branch of science (shall 100,000, up to about 1,500,000 vibrations per ventors and probably the foremost Ameri- we call it science ?) even claim to com- second, we have no sense that can appre- can scientist, has been much impressed by municate with the departed spirits of de- ciate any effect. After that stage its move- some of this so- called mental telepathic ceased persons. ment is indicated first by the sense of tem- or thought wave transmission, and particu- While most of us, in view of the pres- perature, and then, when the rod becomes larly by one expert by the name of Mr. ent great intellectual activities and en- red hot, by the sense of sight. At 3,000,000 Bert Reese. Mr. Ed:son made a number lightenment of the day, are prone to scoff it sheds violet light." of different rigid tests in connection with at all such theories and alleged demonstra- "Now the thought has occurred to me Mr. Reese, and also he made several ex- tions of a new art, it seemingly behooves that there must be a great deal to be learned periments between the expert and employes us to think over the matter more than once, about the effect of those vibrations in the at the Edison plant. Mr. Edison says of when such great scientific investigators as great gap where the ordinary human senses this matter: "Then I asked him to let me Bell, Edison and Lodge will condescend to are unable to hear, see or feel the move - try. In my case I went into another build- look into such things seriously. ment. The power to send wireless mes- ing and wrote down the words 'Is there At a recent meeting of the American In- sages by etheric vibrations lies in that gap, anything better than nickel hydroxide for stitute of Electrical Engineers at New York but the gap is so great that it seems there an alkaline storage battery?' City, where Dr. Bell, inventor of the tele- must be more. You must make machines "At that time I was experimenting with phone, was presented with the Edison practically to supply new senses, as the my new storage battery and felt somewhat medal "For Meritorious Achievement in wireless instruments do. Can it be said, dubious about being on the right track. In Electrical Science," he, in response to the when you think of that great gap, that there the meantime as I folded the slip of paper presentation address accompanying the gift is no field in the further development of containing the above words in writing I of the medal, spoke as follows: electrical science for you ?" filled my mind with a different problem and "What will come next? We now have The illustration herewith gives an idea kept working on its solution so that Reese electric light, electric power, electric speech of how the inductance coils proposed by could not by 'mind- reading' decipher what and a swarm of electric appliances that Dr. Bell would appear on the head for I had written on the slip of paper, and re-

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Will the Day Come When Even Our "Thoughts" Can Be Transmitted From One Brain to Another, Electrically? have come into use during recent years. the transmission and reception of thought turned to the room where I had left Reese. All of our knowledge of the external uni- waves from the human brains. At the moment I entered the room he said: verse is derived from our senses, and Sir Oliver Lodge, in dealing with the de- 'No there is nothing better than nickel science has brought electricity to the serv- velopment of news intelligence transmission hydroxide for an alkaline storage battery." ice of practically all of our senses. Are has declared that it is not unreasonable to "He had therefore read my question ac- you going on? The possibilities of fur - say we will eventually become so developed curately, and to this day I am satisfied that the development are inconceivable." that one man may call another by name, there is nothing better than nickel hydrox- "Men can do nearly everything else by reeking to find him among the millions of ide for that particular purpose. electricity already, and I can imagine them the world's population, and if that man "About two years afterward the boy with coils of wire about their heads com- answereth not then he must be no more in from the gate -house of my laboratory came ing together for communication of thought the flesh. This, indeed, seems to be one in and announced that Reese was in the by induction." of the wonderful objectives toward which gate -house and wanted to see me. I took The audience of 1,000 electrical engineers modern scientific investigat :on is directed. out my pencil and wrote in microscopic and their guests showed no sign of being Dr. Alexander Graham Bell has already letters the word 'keno.' I folded the paper, incredulous, even of this suggested pos- experimented on the transmission of thought put it in my pocket and then told the boy sibility of electrical development. How- over long distances by means of elec- to bring Reese in. I greeted him and at ever, Dr. Bell added: trical induction. The inventor of the tele- once said: 'Reese, I have a slip of paper "But that is for you to make possible," phone and his assistant, Prof. Ellis, capped (Continued on page 254.)

www.americanradiohistory.com 254 THE ELECTRICAL EXPERIMENTER October, 1915

CHURCH SERVICE BY TELE- ergy twice as strong as is contained in an CAN ELECTRICITY TRANSFER PHONE. ordinary stroke of lightning. THOUGHT WAVES? By E. O. Catford. "Since then I have pursued my experi- (Continued from page 253.) In Guernsey, England, if a Sunday hap- ments with that one point in view, namely, pens to be disturbed by the elements, the the discovery of a way of concentrating and in my pocket, what is on it ?' Without a populace can remain at home by their com- absolutely controlling electrical energy. moment's hesitation he said 'keno.'" fortable hearth and listen to the sermon, This result has been attained under the Mr. H. Gernsback, who has studied con- the organ and choir instead of tramping workings of the apparatus for which the siderably such matters as mental telepathy through the rain or snow, as the case may Government granted me a patent last De- and also such matters as "thought trans- be, and then arriving at the church in so cember. mission" in so far as the matter can be irritable and distressed a condition that I now claim that I can confine any studied at this time, has made a suggestion they can hardly and whole -heartedly par- amount of electrical energy, and that, too, which may be mentioned as worthy of trial ticipate in the church service. without the use of insulation. The Mar- in this field. This suggestion embodies the This is accomplished by having the tele- coni and other existing systems of wireless use of a set of one or more sensitive phone exchange connect you to the church telegraphy require that there shall be in- Thermo -couples, which, as we know, pro- by a switch. The charge for this service sulation in connection with the transmitter. duce an electric current whenever they are is 10 cents, but public officials, such as I can now send a wireless current entirely heated. It has been found that invariably police, firemen, militia and others, who are across the ocean. whenever the brain is concentrated on some kept from church services by their duties, "In transmitting a Marconi wireless cur- problem, or thought, that heat is produced are given the privilege free of charge. rent, for example, not more than 20 or 30 in such a way that it will cause the fore- At Platte Fougère Light -house Station horsepower of energy is required; with my head of a person to perspire, even though (Guernsey), where these photos were new apparatus I can concentrate and direct slight:y. Now if this Thermo -couple ar- taken, frequently as many as eight per- 5,000 horsepower of electrical energy. rangement is placed against the forehead sons sit around the table on a Sunday "With this tremendous energy thus con- there is a possibility that waves might be picked up and transmitted over a wire to a proper receiving apparatus or instrument attached to the head of a second person. A theory promulgated by Mr. H. W. Two Views of Telephone Installation on Island of Secor takes for its basis a somewhat dif- Guernsey, England, Whereby Soldiers and Others ferent phenomena. This particular action Can Hear Church Services Five Mlles Away in is nothing more nor less than the Aurora, Any Kind of Weather at Cost of to Cents. which we know exists for quite an appre- Microphone on Pulpit is Marked at Left. ciable distance about the human body. Some time ago a well -known English scientist and investigator made it possible to view these vari- colored aurorae sur- rounding the human body by utilizing spe- cially devised screens, and when looking through these screens the ever -changing aurora about the body could be very clearly observed. Moreover, and in line with Mr. Secor's theory, these aurorae are of dif- ferent colors or hues for different condi- tions of the mind or brain in the person under observation. They are red, or red- dish yellow, when the person is in great anger, and thus they change through vari- ours colors for different emotions. If the inductance coils of Dr. Bell, and proposed by him to be strapped around the head, will work at all, it seems very likely that they would act by means of these aurorae evening, listening to the minister's sermon centrated and controlled I can telephone by discharge from the body and which quite five miles away. wireless across the ocean. I can use the possibly is electrical in its nature. If this apparatus, also, for sending a blaze of light is so then a simple coil at both transmitter TESLA SUES MARCONI FOR over great distances." and receiver end of the line should suffice, in electrical aurorae set- WIRELESS CONTROL. Mr. Tesla in the complaint alleges that as the variation the Nikola Tesla has appealed to the law to up about the body and controlled by the he is the inventor of a system of transmis- brain would then induce corresponding declare that he and not William Marconi sion of electrical energy and of apparatus I is the inventor of wireless telegraphy. for ever -changing currents in the first coil to arranged for that method and system, line second Many millions in money and world -wide which he received a patent, numbered 645; be transmitted over the to the coil. This coil could then, in virtue of the control of the commercial use of the wire- 576, applied for on Sept. 2, 1897, and issued I less transmission of energy are involved in re- fluctuating currents passing through it from March 20. 1900, and for which he also field about the struggle. ceived a patent, numbered 649,621, applied the line, influence the auroral The suit has been brought in the United for at the same time as the other, and the body of the second person on whose States District Court in the name of the on 15, head the coil was placed. issued by the commissioner May pointed by several elec- Nikola Tesla Co., of which the Serbian 1900. It has been out inventor is the president, and to which he trical men, and particularly by Dr. Giuseppe Marconi's application for a patent on Musso, the well -known consulting electrical has transferred all of his fundamental wireless the complaint asserts, patent rights in telegraphy. The telegraphy, engineer of New York City, that quite pos- wireless was filed on Nov. 10, 1900, and was not defendant in the action is the Marconi sibly the points at which to apply these granted and issued until June 28, 1904, be- transmitting and receiving coils, or other Wireless Telegraph Co. of America. ing 763,772. Mr. Tesla announced recently in con- numbered forms of apparatus, is not about the head nection with the suit that he has just been The Tesla company asks the court to de- at all, but at some other vulnerable point granted a patent by the United States Gov- clare the Marconi wireless telegraph patent or points on the body which would have to ernment which will supersede and revolu- null and void, claiming that the Marconi be found by experiment, and also in con- tionize all present forms and applications patent covers the inventions and combina- sideration of the fact that these more vul- of wireless telegraphy and will enable him tions of apparatus described and claimed in nerable points have the strongest effect on and the financiers who are associated with the Tesla patents. the control of the electric charge on the him to obtain and keep a hold on commer- The Marconi company has put in an an- body. He also has said that in thought cial wireless telegraphy. no matter what swer denying any infringement. transference it has been invariably noted may be the outcome of the litigation he The Tesla company also has begun a suit that best results are obtained between two has begun against the Marconi interests. against the Marconi company for alleged persons having a strong affection for each "My earlier experiments in Colorado in infringement of the Tesla patents. other, which in another sense might be 1899." he said, "demonstrated that I was [Ed. N.ote.- Tesla's patents and wireless considered as two minds "in tune" or on the right track, and with a transmitter transmission of energy are covered in syntony. of my invention of not more than 30 inches "Wireless Telegraphy" by Sewall, procur- in diameter I succeeded in concentrating able from our Book Department at $2.15 Are you a regular reader? It will pay and applying an amount of electrical en- prepaid.] you to become one!

www.americanradiohistory.com October, 1915 THE ELECTRICAL EXPERIMENTER 255 Electric Toys That Respond To The Voice ANOTHER novelty for amusing chil- tain sound is produced, suddenly jumps Two very interesting toys are portrayed dren has arrived in the form of up from the case. In the center is a small in Fig. 5; the one at the left, represen ing toys, voice operated by electricity. dog, resting in his minia- These new toys afford entertainment for ture kennel, the doors of which are closed. As soon as an ordinary whistle is blown the doors open and the little animal jumps out so sud- denly that one is almost taken aback at the un- expectedness of his ap- pearance. The third and most interesting is t h e dancing coon seen at the right. This coon W i l l perform all kinds of dances as long as the proper tune or sound is produced. The grate opening in the front of the cabinet is the collector of the sounds which are caused to act on the micro- phone. Fig. 2 depicts a sche- matic diagram of the ap- paratus used within the dancing doll's abode. M is a microphone con- nected in series with a battery and relay D. operating a pair of electro- magnets H, which are connected in series Fig. z. Diagram of "Dancing Doll" Apparatus Subject to Voice with a vibrator L. In Control. Fie. i (Above) Portrays Three Electric Toys operation, when Controllable by "Voice." Fig. 3, (Below) the Depicts interior of Toys. sound waves strike the microphone M, the a device for throwing a "ball" into the resistance of same varies. and the cur- air, while the other is a "Satan's Head" rent strength in the magnet D decreases. concealed in the chimney of the small pleasure -loving youngsters as well as the The armature closes the contacts, X Y, house, as perceived, who immediately ap- adult, and are operated by sound waves ac- energizing the magnet H, and short -circuit- pears at the sound of a voice. tuating a delicate microphone, by which the A very suitable toy for Christmas time various movements of the toy are incited. is illustrated at Fig. 6. This is a tree dec- The toys herewith illustrated are the re- orated with miniature electric bulbs, con- sults of continuous labor by Mr. H. Chris- nected to a circuit, including a microphone tian Berger, the inventor and originator and batteries, as seen at the left. The of the submarine wireless system, which lamps on the tree are operated by the was described at length in the August issue microphone whenever sounds are produced of this magazine. These toys in order to by the blowing of the whistle seen in the operate require solely the human voice or foreground. a common whistle. Nor is it necessary to These extremely interesting electric toys be near the toys; they will operate, for instance, if the whistle is blown 30 feet Fig. 4. A Whistle Will Fire This Miniature distant from the apparatus with a result Field Cannon. ing the microphone. The excitation of the magnet D then again increases and attracts its armature, consequently varying the the fluctuations in electro- magnet H, which in turn operates the doll at Fig. 1, whose hands and feet are made of coiled steel springs. This metal is attracted by magnet- ism, generated by the electro- magnet H. Also the shoes may be of iron so as to be acted upon by the electro- magnet. The interior view of these toys is shown at Fig. 3. The apparatus on the right is a microphone relay, operating any elec- trical device just by the production of sound, acting upon the microphone. The larger instrument, seen in the back- ground of the photograph, is the exact ap- paratus used in the electric dancing coon; while the one towards the left is an auto- EE. matic controlling relay. The whistle here Fig. 5. At Left Shows Voice Controlled shown is used as the sound actuator of Gun. At Right a Disappearing these novel toys. i Satan's Head. Miniature "field guns" are also operated Fig. 6. Electric Lights on Xmas Tree ' Con by sound waves, and Fig. 4 illustrates such trollable by Whistle and Microphonic that is as uncanny as it is startling in its a gun, which is electrically fired and oper- Relay. novelty. ated by sounds produced from the whistle Fig. 1 represents a group of three elec- shown at the extreme right, near the wagon mark a distinct advance in the realm of tric toys. The one at the left is a police- containing the ordinary instruments used amusement apparatus, and it seems this man, enclosed in a case; who, when a cer- for operating the other toys. principle could be well applied further.

www.americanradiohistory.com 256 THE ELECTRICAL EXPERIMENTER October, 1915

A LIGHTHOUSE OPERATED AND ELECTRIC DENTAL SIGN THAT LIMIT TUCKERTON WIRELESS. CHECKED BY ELECTRICITY. DEMONSTRATES "BEFORE" None but Government and Embassy mes- Edwin By O. Catford. AND "AFTER" EFFECTS. sages will be sent by way of the Tuckerton WHEREVER men are placed in an A very pretentious electric sign erected wireless station until further notice. Mes- isolated situation with long con- in New York City for a large dental parlor, tinued responsibilities the need as shown in illustration and the small in- sages for Germany and Austria must be for some kind of check or inspection be- sert picture, shows the countenance as it forwarded by way of Sayville at the same comes evident. Personal inspection in is supposed to appear before \siting the ra es. such cases is necessarily infrequent and dentist, and the therefore inefficient. The men concerned, larger photo the sat- if they are competent and keen on their isfied smile and im- work, will welcome any device which is an proved appearance PALACE aid to efficiency. of the teeth after Some devices of the writer's in use at taking treatment. DENTISTS Platte Fougère Lighthouse Station, Guern- This sign is a sey, England, may be of interest, since they large affair and is Urekt, constitute the equivalent to an hourly in- made entirely of is spection day and night, year in and year opal glass, which 'EME out, with the advantage of automatic and lighted up from the therefore absolutely impartial working. interior of the sign Ohl A clock is provided with a roll of paper by means of electric PALACE 41111 attached on which the man on duty records bulbs properly ar- his signature each hour. This clock is also ranged. These are DENTISTS used to note the time of starting and stop- operated by a motor ping the "fog signal," and in the event of driven flasher, so any dispute arising in regard to these.simes that the two dif- the clock record proves invaluable. ferent faces appear Several electric attachments have been alternately. T h e added by the author to this clock. features of the ohidx First, some contacts insure that if the countenance where man on duty has not "signed on" the clock the two teeth are will set three electric alarm bells ringing shown missing is at 20 minutes past the hour. also caused to These bells are situatcd, respectively, in change, so that the the engine room and in each of two dwell- general appearance ing houses, so that they serve to call out is one of sadness or ?ÄL.ácÉçq6 the keeper who is off duty. Thus this clock pain. may This novel elec- w truly be said to be equal to the pro- f vision of an hourly inspection day and tric sign is one of night. the well -known Should the man on duty meet with an Federal line, and at- tracts unusual in- accident during the night, which is always 9 possible with dangerous machinery as used terest in the endless l;¡' i for fog signaling, without these clock at- crowds that throng tachments he would simply lie until morn- the "Gay White ing with the added probability, almost Way" of the Old amounting to certainty, that the machinery Town. also would come to a standstill with the Such electric signs as here described fog still remaining. FL The clock insures that should an accident are a great improve- ment upon those of occur which disables the man on duty so Top View Shows "Before" Appearance of Face, and Lower Illustration, that he cannot sign at the clock, at 20 min- a few years ago, "After" Effect, Produced in New Electric Sign. to be sure.

At Left: The Lighthouse That Checks Itself Elec- The clock is also a complete safeguard ashore when less than a fortnight's supply trically. Below: T h e against sleepfulness Wonderful Electric Clock at night, for which of acetylene remains for the light. That Compels Exact felony it provides instant punishment. Double pole contacts are used so that no Service From the Men The writer can testify that it is a most battery leakage can take place through the in Charge. disagreeable experience to hear the bells cable when the test is not being made. ring out at night and to realize that the Those who know the insidious electrolytic whole of your own household, as well as troubles liable to introduce themselves that of your neighbor, has been aroused wherever any continuous leakage of cur- from sleep by one's own delinquency. rent, however small, becomes possible will In order to give an indication that the appreciate this point. electric alarm attachment is in constant or- Thcse indications are useful at all times, der, it is so arranged that each bell gives but they are doubly appreciated on days a single stroke every hour. and nights when the sea dashes with ter- This notifies that all is in order and in- rible fury on land and lighthouse, and it is cidentally shows in both houses that the evident that many days must elapse before clock connections have not been tampered a visit to the lighthouse will become pos- with. Twenty minutes later the alarm bells sible. ring out in earnest, unless in the interval To be able then, simply by lifting a handle the man on duty has "signed on" at the (in safety) ashore, to obtain assurance as clock. to the condition of affairs on the storm - The recording clock with the author's swept lighthouse is no small gain. electric attachment compels the lifting of the clock handle once every hour. AUTHORS! ATTENTION! Seizing on this fact it was next arranged What ideas have you regarding the con- that by means of further electric contacts struction and operation of wireless and attached to the handle a testing current electrical apparatus? Why not write up passes out to the lighthouse through one these ideas and experiments for the benefit wire of the cable, returning by another wire, of the Electrical Experimenter readers and each time the clock is operated; that is, thus help yourself and your fellow -worker once every hour day and night. at the same time. We are pleased to re- This provides a test for continuity of ceive contributions of the above character utes after the next' hour the alarm will the cable, it also indicates that the electric with plain ordinary sketches or photo- automatically be rased and the second man lamps and electric lighting circuit are intact graphs and pay regular rates for all such called out to duty. -Thus by calling aid the and, further, by means of a special pressure matter published in these columns. Ad- clock might save a man's life. gauge on the lighthouse it gives warning dress all communications to the Editor.

www.americanradiohistory.com October, 1915 THE ELECTRICAL EXPERIMENTER 257 AN ELECTRIC BACTERIOLOG- Installing A Complete Electric Service in 15 Minutes ICAL INCUBATOR. As one of the features of the annual field violation of the company's safety rules was By Frank C. Perkins. day and outing of the Commonwealth to result in disqualify ;ng the whole gang. The accompanying illustration shows a Edison Company, of Chicago, service gangs Three judges with stop watches took the most interesting electric bacteriological in- from each of the company's three over- time and observed the work as it proceeded. cubator said to be in advance of the gas - head districts competed in a service in- In addition to the prize money offered to heated devices now generally used on ac- stallation contest. The crew representing the winner of this contest as one of the count of the extremely uniform tempera- ture regulation pruv:ded. It was developed at Salt Lake City, Utah, and is so designed that when once adjusted to the desired temperature, it is claimed, it will operate for days at a time without any IStLi.1 attention. The lncubator is heated with ' electric resistance coils in the top of the ev ice. It may be stated that there is a wafer f.` y thermostat inside the machine which ex- pands with rise in temperature and pushes t piston stem which raises and lowers a balanced lever arm carrying tw , electric contact points. These two contact points dip in mercury cups, which are connected c. in series with one side of the circuit. \\/hen the temperature inside the incubator reaches the desired point the contact point is lifted out of the mercury, thus opening the cir- cuit. When the temperature falls just a small fraction of a degree the contact points are lowered hack in the mercury and the circuit is closed, thus bringing the machine back to the proper temperature. It is held that a variation of less than ''.1 degree will cause the device to operate !it and to open or close the circuit. Temper- ature adjustment is obtained by means of a small screw. The incubator consists of a double -walled box having a 0.5 -inch air r space between the outer and inner walls. The box is finished in mahogany and is ,quipped with double doors, the inner door y having a glass panel so that the contents of the machine may be readily inspected EE without opening the door. By means of the button seen on top of the machine a miniature lamp inside the in- Insert Above Shows Service Gangs Installing Apparatus in Prize Contest. Lower View Portrays Transformer and Pole Work Contest. cubator can be turned on. The max mum input into the machine is 50 watts, and the average input per hour is about 25 watts. each district had previously been selected regular field days events, an added bonus It measures 8 inches in width 'and 10 inches by elim.nation contests conducted in regu- of two cents for each second under 20 in height. with a length of 16 inches. lar service -installation work during the two minutes was provided for weeks preceding the field day. each man in the winning Before the day of the final competition a crew. pole line carrying primary wires on single None of the gangs were arms was erected on the field. A platform disqualified for violating the on which three sections of brick wall were company's safety rules. The mounted was also erected at a distance of winning crew was, however, 75 feet from the poles. Above it were penalized 15 seconds for placed three regular service outlets con- spilling solder. nected to groups of lamps. Each gang con- sisted of a foreman, two linemen and a groundman. The foremen were not al- YACHT'S "MONEL" lowed to do any work. Sitting in their METAL HULL RUINED trucks, which were loaded with standard BY ELECTROLYSIS. tools and equipment, the men awaited the Alexander Smith Coch- signal to start. ran's magnificent schooner The ruses of the contest required eaçh yacht "Sea Call," after being crew to do the following work: Cut a in commission only six weeks, gain and bore a hole for a buck arm on the is now being broken up for pole; install the buck arm with braces and scrap in the yards of her primary cut -outs; hang a transformer; builders at Neponset, Mass. connect the transformer to the primary cir- The "Sea Call" is a splen- cuit and to the service drop; install a did sailing yacht with auxil- bracket with three Pierce bolts on the br:ck iary gasoline engine. She is An Automatically Compensated Bacteria Incubator win wall; run a 75 -foot two -wire service from being knocked to pieces on Electric Heating Coils. the pole to the bracket, and connect the account of the disintegration service to . the outlets. All joints were to of her bottom through elec rical action. be soldered and properly taped. The last The electrolysis which has damaged the bottom, but reports from Neponset say thing to be done was to insert the primary bottom of the boat is said to be due to the that, while the action did start around the plugs to light the lamps above the outlets, use of a steel skeleton and a bottom of stem and stern posts, which are of steel, it indicating that the work had been com- monel metal, an expensive alloy composed resulted in the deterioration of the monel pleted. Any failure to complete the job of, roughly, two parts nickel to one part into "a chalky substance." It is said that according to the company's standard prac- copper, with small additions of other there are evidences of deterioration in the tice was to result in a penalty equal to metals. monel plates of the bottom, but the sugges- three times the time it would ordinarily It was understood that electrolysis affected tion has been made that this is only discol- take to do that part of the work. Any the steel skeleton and not the plates of the oration due to the electrolysis of the steel.

www.americanradiohistory.com 258 THE ELECTRICAL EXPERIMENTER October, 1915 TELEPHONE THAT TELLS WHO CALLED WHILE YOU WERE A Telephonic "Nursemaid" and a Bird Alarm OUT. On a single -wire, par , -line telephone The accompanying illustration shows the telephone, devised also by E. O. Catford circuit near Constableville, N. Y., each application of the telephone as a nursemaid for the benefit of his little son. subscriber is provided with a telephone in- as devised by an ingenious Englishman. As cats kept birds at a distance from the Open air life is undoubtedly best for babies, house so that this little boy could not have who indeed, showing a wisdom beyond the pleasure of watching them feed from their years, sleep at once out of doors after crumbs thrown out, a cat -proof tray was strenuously refusing to sleep inside the therefore set up in front of the windows house. The difficulty has been that where at some distance from the house and here there is no housemaid the busy mother robins, finches and other birds came to cannot spare time to be constantly outside feed. looking after baby. It is of interest to note that the tele- The photograph shows the details of a phone transmitter was then added, so that plan successfully employed by Edwin Cat - when the birds sang they could be listened ford, the engineer -in- charge at Platte to in the house. Doubtless a better plan Fougeré lighthouse, Guernsey, where the would have been to conceal telephone baby carriage is provided with a cigar box transmitters among the branches of bird - containing a telephone transmitter and a frequented trees, but here there were no small clock. Wires running up to the trees available. The transmitter in use is house. 30 yards away, enable the mother the ordinary k'nd used for speech and is

Nor el Telephone Set That Tells Who "Called" While You Were Out. strument equipped not only with a selective ringing attachment, but also with a device to inform the subscriber who, if anyone, called in his absence. The instruments were constructed under specifications covered in -'-- a patent issued to P. G. Bernholtz, Con - stableville, N. V. They differ from the standard ground -return telephone in that a / special battery has been added to the local circuit and a visual signal or drop, as well as a bell, has been arranged to operate through an especially designed selective -

signaling mechanism. - To call a subscriber on a line equipped t#n with these instruments it is necessary to close the special battery (B) circuit through the push- button. The special battery op- ' erating all relays (R 1 on the line unlocks '. V t ali instruments. The indicator then moves automatically to the desired number, and when the line is again energized the se- . lective- signaling apparatus in the called subscriber's instrument rings the bell and `N operates the visual signal or drop. Other , instruments return to their normal posi- tions. If it so happens that the called E.E. party is not within earshot of the bell, he notes on his return that the visual signal has been operated. He then places his in- A Telephone Nurse Maid (at Left) an d an Electric Bird Alarm (at Right). dicator on R and energizes the line by means of the special battery, ringing all bells on the line, but failing to actuate any in the intervals of work to listen for baby's protected from rain by an inverted cocoa of the visual signals because the indicator cry; if at the table and during meals it is tin, well painted, open at the lower end to was set at position R. Hearing this call easy to l'steti continuously. freely admit sound. After months of this and observing that the visual signal has A clocc attachment was also provided. outdoor use the telephone remained in per- not been disturbed, all subscribers under- "No news is good news" does very well as fect condition. a popular saying, but the elec- trical engineer knows better, TELEPHONE NEW POLICE AID. for no news often means a Police Commissioner Arthur Woods an- hitch in the means of com- nounced recently that the New York Tele- munication. In this case the phone Co. will co- operate with the police clock is added so that the department in capturing criminals. The sound of its ticking may in- territory within 100 miles of New York has dicate that the telephone is been divided into seven zones, and as soon transmitting sounds correctly. as headquarters notifies the telephone com- The device proved entirely pany descriptions of men wanted will be successful through baby's first sent to all the zones. year. Not only was baby's cry Within a few minutes all chiefs of police, distinctly heard, but also the sheriffs, constables and railroad station men comments of persons not can be on the lookout. knowing of the telephone in the cigar box who approach the spot on the common where WIRELESS AND PIGEONS. baby sleeps. A rain alarm was Recent experience has tended to show also evolved to give warning that carrier pigeons and other birds of by passage are guided by magnetic currents. causing an electric bell to W. A. ring should a shower come on. Thauzies, a French student of The second illustration pigeons, has noted that on two occasions shows an interesting birds' when pigeon flights were unsatisfactory Circuits of New Tell -Tale Ielephone Set Illustrated Above. magnetic storms were occurring; and the flights of these birds have been becoming stand the signal, and only the one who pre- dividual with whom he desired to commu- often uncertain and erratic since wireless viously called and failed to obtain the in- nicate is supposed to answer. telegraphy came into extensive use.

www.americanradiohistory.com October. 191:, THE ELECTRICAL EXPERIMENTER 259 WIRELESS ON MOTORCYCLE TO An Electro- Magnetic Nail- Packing Machine PACIFIC COAST. By Frank C. Perkins By A. J. Geiss. Mr. and Mrs. Wengatz, of Albany, N. THE accompanying illustration, Fig. 1, trough in quantities of about l0 cwt., F., passed through Toledo, O., on their shows an interesting electro- magnetic whence through the action of the shaking way to the Pacific Coast on July 20 last. nail -packing machine developed at device they glide gradually into the paral- Mr. Wengatz will be joined later on by Zurich, Switzerland, while Fig. shows the leling mechanism and then, while still fall- Fred Wallace, also of Albany. Their out- scheme of packing and indicates the saving ing, are drawn in the direction of the mag- accomplished with this orderly method of netic lines of force. As a.consequence t.tcy doing the work as devised by Otto Gam- are paralleled in a mathematically exact per. Note the new style packages at the manner. The objects, thus arranged in right of Fig. 3, containing as many nails parallel and held suspended in the paral- as the keg in the center. leling mechanism by the lines of force, are One type of this electro- magnetic na`.1- by means of a lever, which simultaneously packing machine is suitable foe paralleling cuts out the magnetizing current, pressed and packing nails 2 to. 0 inches long, and a into a tray which is fixed between the two special construction for nails 2 to 10 inches magnet poles. This sheet iron tray swing; long. Until recently, in spite of the fact downward, and from it the objects get that for a long time in the nail industry wnptkd by a slight jerk into the paper

Wireless Set on Motorcycle Bound fo Pacific Coast. tit consists of a Dayton motorcycle with side car and trailer. They carry a com- ?Ig. i at Left: plete wireless telegraph outfit, and Mr. Latest Type Wallace, who is a licensed radio operator, of Electrically Operated Nail - will communicate with wireless stations at Packing Ma- distant points along their route. They ex- chine. It Re- pect to reach the coast in three months, quires About i/2 Horsepower and if the war ends this fall the trio ex- Direct Current pects to make it a tour of the world. for Motor and Sorting Mag- THE SMALLEST ELECTRIC net. MOTOR. A motor recently completed by Ivan T. Nedland, a jeweler of North Dakota, weighs only 5.; grains and is said to be the smallest motor in the world. Its com- mutator, which measures 0.045 inch in diameter, is made tip of four gold seg- ments insulated from each other with mica. No glue or cement was used in its con- struction. The shaft on which the com- is mounted is made steel and is Fig. x at Right: imitator of Illustrating at 0.009 inch in diameter. Fiber insulation Extreme Right the Small is used between the commutator and the Space Occu- shaft. The tiny armature, 0.09 inch in pied by Nails diameter, has four pole pieces and is Packed by wound with No. 40 silk -covered copper New Machine. These Boxes wire. The weight of the revolving part is Contain as 1.25 grains. Between the armature and the Many Nails yoke two field coils are provided. The as the Keg in the Center or silver brushes measure 0.012 inch in diam- the. Box at the eter and are held against the commutator Left. by springs 0.004 inch in diameter. In over- all dimensions the motor measures 19/64

here has been felt the need of a really packet, the mouth of which is placed over practical paralleling and packing machine_ the end of the tray by the operative in no one has succeeded in designing an ap- order to receive them. paratus capable of performing the time - It is stated that this simple working wasting operations of paralleling and pack- cycle, making it possible for a girl to at- ing of nails in a thoroughly satisfactory tend to the machine, can be repeated so manner. rapidly that one workgirl trained to a cer- This packing machine is based on the tain extent for such work can in one hour principle well known to every electrician, deal with ordinary nails of No. 6 -6 -inch that all linear iron objects, as soon as they equal to 1,700 to 2,400 pounds in packets are brought into a homogeneous magnetic of 10 pounds each and No. 10-31/2-inch field, must adjust themselves automatically. equal to 1,300 to 1.600 pounds, in packet; under the influence of the magnetizing cur- of 7 pounds each, while moulders' nails rent, in the direction of the magnetic lines are handled at the rate of No. 15 -6 -inch of force, which, as is well known, always equal to 600 to 800 pounds in packets of run parallel to each other. This being so, 10 pounds each and nearly the same num- it, of course, follows that this machine is ber of packets of 11/2-inch, 2 -inch, 3 -inch not only suited for the paralleling and fill- and 4 -inch nails. ing of nails, but that it can be equally well It is claimed that the above quantities used for packing all magnetically excitable represent the following values when coin linear objects, such as wire rods, coach pared with those dealt with by hand: Or- Said to be the Smallest Electric Motor in screws, hairpins, pens and knife blades. dinary nails, 4 to 5 times the quantity dealt the World. It Measures 19/64 Inch It will be noted that the machine con- with by hand, and moulders' nails, 10 to Long. sists of two main parts, a paralleling 15 times the quantity dealt with by hand, inch long and 11/64 inch high. All visible mechanism and a feed trough above it. into involving, of course, a corresponding sav- parts are finished in Roman gold. When which a shaking device is fitted. The ob- ing in wages. connected to a small flashlight battery the jects to be packed are emptied into the feed (Continued on rage 260.) motor runs at a very high speed.

www.americanradiohistory.com 260 THE ELECTRICAL EXPERIMENTER October, 1915 ELECTRICITY ON GERMAN SUB- submarine, the terror of the undersea. The ELECRIC LIGHTING AT PANAMA MARINES. illustration herewith shows the compactly CANAL. Electricity plays the leading role in the arranged electrical and gasoline engine unit Our illustration operation and navigation of the modern installed in a modern German submarine, shows the beautiful elec- trical illumination of the Panama Canal half of the hull of the boat at being the Pedro Miguel Locks. The power- ¡¡: left off, so as to show ful electric lamps tR -. - .y _ a sectional are placed on tall con- ! 1'L view. Those in- crete columns. The electric current util- . _,--- terested would do well to - ized for these lamps is generated at the peruse an -- exhaustive article Gatun Spillway. These ornate lamps . ,! entitled "Electricity, serve I II _ the a double purpose. They permit the pass- Power Behind the Submarine ing of the vessels I Boat," through the canal at which appeared in the night and also make it \) July, 1915, issue easier to guard the t...... 4, of this jour- locks from an attack by an enemy in time :: nal, wherein all of the im- of war. portant functions of the . A. electrical installation of _ _ modern submarines are fully discussed t ; and illustrated. The submarine of to -day : is one of the most highly per- l ' f e c t e d mechanisms ever wrought by the hand of ` . man, ~ and enables the crew of ` . same e to sank beneath the surface Í . of the sea and to cruise in . ` M ' this fashion, submerged en- -r.; 'j " tirely from sight, for a dis- '1 ; -0, tance of 100 miles or more, - w y t 1.tficient Electric Lighting Will Help to without coining to the sur- Guard the Panama Canal. .f Í - face for air. Special air ` ;y-"n pur:fiers and regenerators are . provided. Powerful electric EDISON'S SECRET. storage batteries drive the Thomas A. Edison says new methods . N, K-i - 4t of n `` motors connected to the pro- slaughter are in their infancy to -day, but / pellers of the boat when un- that he cannot find it within himself 2 ` .- to work 1/ 1 der water. On the surface along any line looking to the destruction of -. the gasoline engines are gen- life. erally used for cruising and, EE He says the possibilities of chemistry and simultaneously, these a l s o electricity drive the motors as dynamos, have hardly yet been touched upon in modern warfare, that he knows of Photo (C) by Underwood & Underwood. thus generating current for more Remarkable Interior View of a deadly things than the gas bomb that German Submarine, Showing charging the storage batter- he could invent, the Powerful Electric Motors. ies. These boats carry wire- "but I can't get myself to work on any such stuff as that. I don't less installations of consider- want HOW "PUSSY" RINGS THE DOOR able range, as well as the very latest to destroy life; I want to make the types world a BELL. of submarine signaling devices, operating better place to live in." An interesting photograph is shown here- on etheric as well as on the sound wave It's a beautiful thought of the great in- with of an intellectual rat owned by Mr. principle, whereby telegraphic signals can ventor. But maybe in the secret he holds is E. L. Catford, of Guernsey (England). be transmitted. from one submarine to an- the awful something that would compel The feline announces his desire to enter other through the water and also from a world peace. submarine to its mother ship or tender. The latest vessels of this class have a control arrangements provided and which large cruising range of several thousand are all quickly available by means of a miles before returning to their base, and concentrated group of push buttons at the they can he submerged and raised from commander's side, when he is scanning the the sub -surface very rapidly, owing to the sea through the periscope for possible ingenious and highly perfected electrical victims.

is closed, which rings the electric bell on 10 -15 per cent. saving in delivery charges the interior of the house. owing to reduced tare. With very little training this particular The electric drive of the machine is of member of the cat family soon learned to - interest. It requires about 1/2 hp., either hop on the shelf whenever it desired to from a high -speed line shaft, or where come in, especially during storms, and now electric driving power is available from a makes regular use of the shelf, no matter motor erected on the machine. This latter what kind of weather ensues. drive is to be preferred because the pack- ing machine is made independent of the line shaft. AN ELECTRO- MAGNETIC NAIL - The electric current required is small. PACKING MACHINE. The feeding the magnet coils, the cur- front page 2:9.) of (Continued rent for which amounts to about 1.5 kw. hours per day, takes place by direct con- It is pointed out that taking the average nection to an supply reduction in to be 50 per cent. for existing direct current volume line having a tension of 110 to 220 volts. nails arranged in parallel, as compared Where no direct but alternating current with such nails shaken loosely into boxes, or in energy is available the necessary direct cur- kegs barrels, the aavantages connec- rent is a in in- generated by small converter. If tion with packing boxes and barrels there is energy clude 45 per of no electric available the 30,to cent. saving wood same is generated by a direct current gen- through using smaller boxes, kegs or bar- erator mounted on the packing machine. rels 10 to 15 per cent. saving in de- and The machine is 5 feet high and takes a livery charges through reduced tare, also up space G feet 8 inches to 4 feet 4 inches and 40 to 50 per cent. saving in storage. is by using ma- its weight is about 13 cwt. ' Pussy" Gains Admittance by Hopping on It maintained that this this Electric Alarm Shelf. chine for box filling one obtains 50 per cent. reduction of space with ordinary OUR NOVEMBER ISSUE the kitchen door by sitting on the small nails and 70 per cent. reduction of space will contain a wonderful article on "Seleni- shelf observed in the photo. When the cat with moulders' nails, also a 3045 per cent. um." You cannot possibly afford to miss sits on the shelf an electrical contact spring saving of wood by using smaller boxes and it.

www.americanradiohistory.com I October, 1915 THE ELECTRICAL EXPERIMENTER 26I

NEW SCALE FOR WEIGHING LAMP FILAMENTS. Marconi Heads Wireless Corps of Italian Army. A precision torsion balance of special Signor Guglielmo Marconi, the famous latest apparatus known to the art. Mar- design is shown in the illustration here- Italian wireless inventor, is seen in our coni is to Italy .what Edison is to the United with. This device is used in general for photograph herewith at the key of a large States. He has rendered a service to man English wireless station located at London. kind that will not he forgotten f-,r centuries This was taken on his recent trip to Eng- to coin =. land, where he went on spe cial business regarding some new wireless sets he has re- cently developed for the use of the soldiers in the field and which are said to be small enough and efficient enough to permit officers ob- taining information while on the battlefield without utiliz- ing the more cumbersome "trunk" sets making up the regular radio equipment of the signal corps division. Signor Marconi is at the head of the wireless division of the Italian army and navy and, needless to say, their equipment will be second to none in the great European war. This master genius has had wonderful opportun:ties to test out wireless telegraphy over vast distances and with all kinds of apparatus in a more practical way perhaps than has been possible for any other engineer or scientist of our day. It has not always been so, however, as many of our greatest in- ventors and scientists, notably Precision Torsion Balance for Weighing Hertz, have unfortunately Lamp Filaments. never seen their ideas com- mercialized to any such ex- weighing extremely light bodies, but its tent as has Signor Marconi, principal application is in connection with The Marconi corporations to- Photo (C) by Underwood & Under,nod. the incandescent lamp industry. In the day operate over the greatest Signor Marconi at the Key of a British Radio Station. manufacture of incandescent lamps it is ranges and utilize the very A Recent Picture. essential that the filament possess certain characteristics, one of which is that its COMPLIMENTS serves as a dark -room lamp with the red length and, therefore, its weight shall be ARLINGTON WIRELESS. bulb turned on or, with the Mazda lamp, uniform within certain predetermined lim- Captain Gowan, master of the Johnston a safe light for Velox developing. its. While high accuracy is, of course, liner "Swanmore," at Baltimore, pays a A particular feature is an automatic requisite, the instrument must at the same high compliment to the perfect working of masking device. Thin metal strips which time be rugged; and these two features are the Arlington wireless station. Captain may be adjusted as desired mask the paper embodied in this instrument. Gowan states that when 1,400 miles off the with perfect accuracy, so that prints with In use the balance is set on a vibration - Amer:can coast he is able to catch with white margins may be obtained from any less table and carefully leveled by means great clearness the noon -time signal sent of the leveling screw and plumb bob. The out from Arlington. So clear does the filament is then hung on the hook which is signal come that each tick of it can be shown projecting from the right side of heard distinctly. Beyond 1,400 miles the the case. The moving element is then freed time from the Eiffel tower at Paris is by manipulating the lever which projects picked up, but it is not clear and often through the bottom of the case just to the leaves him in doubt about the réal time left of the vertical support. The large sent out. This superiority of the American pointer is moved slowly across the scale station, Captain Gowan said, was not sim- until the small pointer shown adjacent to ply at times, but was always so satisfactory the hook comes to the zero point. The in- that he rated his chronometers by it with- dication of the large pointer is then that out a doubt as to accuracy. of the weight of the filament which is being tested, A NEW ELECTRIC PHOTO In actual use the manually operated PRINTER. pointer is set at the presumed weight of The "you -do- the -rest" part is one of the the filament, and the position of the small most delightful phases of photography. It pointer indicates whether the filament is is a pleasure, of course, to take pictures, above or below that weight or is exactly but you are not getting all the fun, all the the same. These balances are in general delight t:ll you make them. Electric Printer for Amateur Photog use in practically all the lamp factories in For printing there now comes the kodak raphers. this country. - amateur printer, a new thing -new of ne- cessity embodying, as it dzes, the very latest film negatives from the vest pocket up to ideas in photographic printing, and including the 4x5 and postcard size. A HOW ELECTRICITY GROWS IN The printer consists of a box with a re- hinged frame holds the negative and paper SOUTH. movable top in which is located the printing tightly together. In 10 years South Carolina's jump in glass. Inside the box are two electric lights The exposure is entirely automatic. When consuming electricity by the kilowatt -hour -one, a small, red bulb which supplies the the hinged cover holding the negative and was from 18,000,000 to 356,000,000. This is necessary illumination for the adjustment paper is closed the Mazda lamp is auto - the largest proportionate gain of any State of negative and papers, the other, a power- matically turned on, when the catch is re- in the country. New York leads in output ful Mazda lamp which provides the print- leased the Mazda lamp is extinguished and of electrical energy, more than 2,000,000,000 ing light. At the side of the box is a the red bulb burns. This arrangement kilowatt -hours being used in 1915. window covered with orange fabric which prevents wasted current in making prints.

1

www.americanradiohistory.com 261 THE ELECTRICAL EXPERIMENTER October, 1915 NEW COMPACT BATTERY CHARGING SET. How The "Movies" Exploit Wireless The new battery charging outfit shown We reproduce herewith illustration from instrument somewhat resembling a Gal- one of the popular "movies" of the day, vanometer. This device is one of Prof. herewith is designed especially for service in garages for charging automobile igni- tion and lighting batteries. This outfit con- sists of a small motor -generator set on which is mounted a small switchboard panel bearing all the switches, instruments, etc., necessary for their control. The out- fit is to be connected to the incandescent lighting circuit by means of lamp cord and plug, the motor generator being supplied for service on 110 or 220 volt, 60 cycle, alternating current circuit, or on 110 or 220 volt, direct current circuit. The motor generator is supplied to de- liver direct current at 12, 18 or 24 volts, such voltage being specifically adapted for charging 12, 18 and 24 volt batteries. The switchboard, which is mounted upon these sets, has a snap switch in the line circuit for the purpose of starting and stopping the set; a snap switch in the cir- cuit from the generator to the batteries to be charged, for opening the charging circuit; a voltmeter for reading the voltage delivered by the generator ; an ammeter for reading the charging current, and a held rheostat for raising or lowering the volt- age of the generator end of the set and, therefore, serving to adjust the battery - charging current. This set needs practically no attention in service other than an occasional filling of the bearing grease cups with oil. The switchboard, bearing all of the instru- ments, rheostats, switches, etc, properly An Exciting Moment in "Romance of Elaine" Film When the "Wireless" Helps to Locate wired, leaves as the whole work of in- the Conspirators. stallation simply the necessity of connect- ing to lighting circuit and to battery by known as the Romance of Elaine, in Arnold's marvelous inventions and when lamp cord. which wireless telegraphy plays an im- connected to any wireless set is supposed to portant rôle. The picture in ques- show how far away and exactly in what tion shows Prof. Arnold, as he is direction a wireless station lies and froth known in the filin e.pilode, which which the signals are being received. is entitled "The Wireless Detec- Truly, this is a little ahead of applied tive," at the special wireless set on science in this direction, as while we have hoard his yacht. He is seen pick- the Radio -Goniometer, which will show ing up secret radio signals being quite accurately the direction in which a sent out from the hidden station wireless station lies. we have not as yet of the conspirators, who play an any instrument which will show how far important part in this exciting away a station is when signals are received torv. from saine at any other radio station. Pos- The wireless outfits used are sibly, however, such a device will be used quite ordinary, generally speak- by future radio engineers, and thus it is ing, but in our photo may be seen that the "movies" pave the way unwitting- (at the left) lying on the table an ly in scientific advance, so it seems. alice to the flow of current. of liquid matter the resistance is much re- It has been estimated by capable duced. authorities that the resistance of Nervous people have been found to have the human body is about 10,000 a very low resistance, as have also heavy ohms, but it varies greatly with smokers and drinkers. the path the current takes through the body. If a person firmly grasps two metal conductors the INVENTOR CLAIMS TO GET resistance from one hand to the other is only from 1,000 to 3,000 CURRENT FROM AIR, ohms. If a shorter path be taken, Following the same principles as those as for instance through a man's involved in wireless telegraphy, A. Bloom- head, the resistance is very much field, an oil district inven'or of Perneta, less. Okla., claims to have discovered a method Some interesting experiments of drawing current from the air and suc- have been made relative to the cessfully propelling a motor without other conductivity of the human body, power. So successful has he been in his and it has been found, by means demonstrations that the Federal Govern- of very delicate instruments, that ment has taken it up and has asked the in- the resistance of the same body ventor to take his model to the Brooklyn New Compact Type Storage Battery Charging Set. varies constantly, even different Navy Yard for a test. human moods affecting it. The model which Bloomfield has made is RESISTANCE OF THE HUMAN A change of diet also makes a difference. a small motor of about one -quarter horse- BODY. while such a slight event as a third person power. By means of a mast, erected to a A human being is not generally looked entering a room causes a change in the height of 75 feet, the current is drawn upon in terms of ohms, yet if a man grasps result. One very variable element in the from the air and the motor is operated. two oppositely charged terminals. he be- result is the resistance of the skin. When [En. -Such schemes do not seem to be comes as much a part of the circuit as the dry, the skill may be regarded almost as practical, and we have our doubts about wire itself, and he offers a certain resist- an insulator, but by having the pores full this one.]

www.americanradiohistory.com October, 1915 THE ELECTRICAL EXPERIMENTER 263

LARGEST STATIC MACHINE IN AN EXTREMELY USEFUL HAND from the switch, is conveniently located for THE WORLD. MAGNET. operation by the thumb when grasping the What is claimed to be the largest Holtz The hand magnet here described is de- handle. Pushing the button closes the cir- type static induction machine in the world signed for operation on 110 or 220 -volt cuit to the coils and makes the magnet is that shown in the illustration herewith. direct-current circuits, and is furnished operative. Slight release of the button It was built by a well -known New York with a 4 -foot length of reinforced flexible does not cause the circuit to be opened concern. The relative size of this mastodon cord and a standard attachment plug. until the ..anon reaches almost the normal position, when the switch mechanism op- erates with a quick break and opens the -- - nülli_inJl7uilil;l/ll if/... . circuit. The magnet then becomes de- x Lut a:lu,wuulu UltUtlll:i6:8: energized. The hand magnet is used in machine shops for clearing chips and borings out of the machinery or removing them from parts of the work not easily accessible. Dropped tools, bolts. boring bars, etc., are easily recovered with the aid of the magnet from places from which it would be diffi- cult to fish them by ordinary means. The weight of the hand -magnet is only 7% pounds. In shops where large quantities of brass and iron filings accumulate the hand -mag- net is useful since brass being non -mag- netic is not attracted by the magnet, like iron, thus enabling the two metals to be separated by merely passing the magnet through the mixed metals. . vx14a :saswt4:4!!' In foundries this magnet may be used to pick up hot or awkwardly shaped castings; smooth plates, which are sometimes diffi- cult to secure a hold on when lying on a flat surface, or for cleansing the molding sand of minute particles of metal. Suspended with its two poles immersed in the liquid, the magnet This is Claimed to be the Largest Static Machine in the World. It Produces Ilea.) will attract to it- 30-Inch Sparks. .. self any particles of iron or steel which it may be desired to remove from the tubs of static machines may be judged by the The circuit to the magnetic coils is close( in which paints, glazes, chemicals. etc., are comparative size of the man, shown in the and opened by means of a quick make-and- mixed. It is also used for dipping can picture. It is in use in the Battle Creek break snap switch mounted in the handle covers, etc. Sanitarium, Battle Creek. Mich., and pres- support. A brass push -button, insulated In the shipping department many hun- vious to its installation at that institution dreds of nails are recovered daily by hand it was set up and demonstrated in the Charles L. Austin ; latitude 45 :30 :45. laboratory at the College of the City of longitude 122:42:30 west ; limited New York, where its merits and electro- to correspondence on ships' busi- therapeutical properties were explained by ness with vessels entering and Dr. Roger Doremus to countless hundreds leaving the port of Portland; com- of the medical and electro-therapeutical posite system, 450 per second; wacr pro fession. lengths, 600 normal, 300 and This monster static generator stands 8 the second. operated by the North- feet high and carries.eight stationary plates western Electric Co., composite and eight revolving discs. These discs are system, 400 per second; longitude 60 inches in diameter and they are excited 122:41 west, latitude 45 :32; wave primarily by a small 30 -inch plate diameter lengths, 600 normal, 300 and 1,700. Töppler -Holtz static machine. which may Fort Adams, R. I., 125 miles range. be observed in one corner of the massive United States Army system, 500 plate glass cabinet, containing the larger per second ; wave length 1,200; machine elements. This machine is capable operated and controlled by United of producing heavy spark discharges 30 States Signal Corps, War Depart- inches long and a wonderful brush dis- ment, and used exclusively for charge of considerably greater length. Government business. Marconi sta- LIST OF NEW RADIO STATIONS tion, at Jualin, Alaska, statistics not ANNOUNCED. available. The Bureau of Navigation of the United Of the new ship stations, the States Department of Commerce announces largest are the Ossipee and Talla - a list of six additions made to the land poosa, each operated and controlled stations of the country in the radio service by the United States Coast Guard, and 16 additional ship stations since its Treasury Department, with range last bulletin on the subject was issued. Of of 300 miles, and the Roosevelt, the land stations, the one of longest range operated and controlled by the Bu- is at Tolovana, Alaska, which has a normal reau of Fisheries of the Depart- reach of 300 nautical miles. The station is ment of Commerce, with a similar located in longitude 149:30 west and lati- range. The Ossipee and Talla - tude 65 north; the wave lengths are 300 poosa are available for the general and 600 meters, the latter normal, and the public, with rates of 4 cents per system is Telefunken, with 1.000 sparks per word, 40 cents minimum per radio- second. It is operated by the Alaska Wire- gram. less Telegraph Co. The Bureau of Navigation has Other land stations establ'shed are: now in the hands of the printer an Rialto, Cal., 250 miles range; Massie sys- edition of the "List of Radio Sta- tem, 200 per second; wave length, 000 nor- tions of the United States," which Useful Hand -Type Electro- Magnet for Lifting Nails, mal, 300 and 1,610; longitude 117:26:53 will be issued within a short time. and Other Iron Pieces. west, latitude 34: 12: 08 north ; operated by Inquiries should be sent to Superin- Southern California Edison Co., limited to tendent of Documents, Washington, D. C. from the sweepings. For work of this sort correspondence with stations of that com- or for handling nails, nuts, screws. etc., in pany. Two at Portland. Orc., each with Watch for wonderful article on "War- hardware stores the hand -magnet is par- range of 150 miles; one operated by fare in the Future" in next issue. ticularly useful.

www.americanradiohistory.com Electric Spark Pictures THE illustrations herewith present veloped will show a gray square or a gray The philosophy of spark pictures is as some new ideas on electric spark round spot. If, however, an object with follows: pictures. a relief such as a coin or similar metal When a spark is made the electrical cur- While electric spark pictures, of course, object is used, and the plate is developed, rent passes between the object and the have been taken right along, our illustra- subsequently, it will show faithfully all metallic plate underneath the photographic tions presets- s o m e plate, the three acting, modifications, and in like a condenser. order to show our 0 Wherever the metal readers how the.:e touches the plate p.ctures are made, a upon developing the short treatise on the negative will show a subject will not be black spot at that, amiss. An ordinary point. When the spark picture is taken negative is printed on. as follows: paper this process is, Any spark coil of course, reversed, from one quarter - and whatever is black inch up to three on the plate will be inches with a fast white on the paper vibrator should be and vice versa. used. Connect one The pictures as lead of the secondary shown in this article termina: to a piece were taken by H. of t:n foil or to a Gernsback, and the piece of sheet metal following explanation or metallic plate is given. Up to this which should be level. time no pictures were Directly on top- of known to have been this, with the gelatine taken of common side upwards, place electrotypes or zinc an ordinary photo- cuts such as are used graphic glass plate. for printing purposes, It goes without say- and it occurred to ing that this opera- Mr. Gernsback that tion must be carried good results might be on in red light, or else obtained if such t h e photographic EE plates were used. The plate will be spoiled. illustrations show the It is also necessary to Some Out of the Ordinary Spark Pictures. (t) Made from Electrotype of Microphone result. and Hand. carefully blind with (rl Steel Rule. (;' Electrotype of "Wireless," (4) Zinc Une Cut of Arm Fig. 1 shows an or- black cloth the vi- dinary line cut, copper brator of the spark coi so the white spark the details which the original article has. electrotype of a microphone which was will not cast l.ght upon the plate. When making spark pictures it should placed face down upon the plate. The re- When everything is ready, take the be remembered that a short spark only sult is clearly shown. metallic object which is to le printed by should be made, and should under no cir- In Fig. 2 an ordinary three -inch steel ruler was used, and in the original photo- graph all the details down to the division of 1/64 of an inch were clearly shown. These details and also the details of the other three photographs have been lost in the half -tone process by making the plate for printing the illustrations in this maga- zine.' //Fig. 3 shows;, another; copper electrotype :it:rl1,

Above: Original Zinc (Line Cut) from Which Spark Picture at Left Was Made.

At Left: Beautiful Spark Photo Made from Zinc Cut Shown at Right. Note Port' Holes "Illuminated" by Spark Effect. electricity and place it face down directly cumstances last longer than a second. Just with the word "wireless" on it. on top of the photographic plate, so it is starting the vibrator for a fraction of a Fig. 4 shows an ordinary zinc cut illus- in contact with the sensitized gelatine. If second will usually give best results. Pic- tration. This cut originally illustrated an the object is square or round without any tures taken with more than two seconds article on page 66, June issue of this maga- relief on its face, the negative when de- duration usually come out too black. zine. It shows much clearer in the ortg-

www.americanradiohistory.com October. 1915 THE ELECTRICAL EXPERIMENTER 265

final print. As will he seen, everything is taper tube leading tu the horn. The tube i interfered wish, due to the excessive noise reversed, i.e., white is black and black is finally connected to a pneumatic sound -box of the engine, etc. white. The turntable of the machine, which These aero -phone sets utilize a regular The aurorae which show around the holds the disc records, is in the present head -band, specially made and carrying two illustrations are simply stray sparks dur- compact type watch case receivers, as oh- ing the time the spark was made. served. These receivers are held against picture are ears by the spring head band, so that Fig. 5 shows a unique spark practically all of the extraneous disturbing made with the above process, and this also noises are thoroughly excluded. The spring was a zinc cut, and was originally used tension, however, is so 52, arranged that the in the Electrical Experimenter; page entire outfit is not in any way uncomfort- June issue. We reproduce the original cut able for the wearer of the phone. Special so it may be compared with the spark pic- microphone transmitters are provided with ture. It will be noted that a curious ef- soft rubber caps on each, strapped to the fect is produced, and attention is called chest at a point below the collar bone and to the port holes which seem lighted up, above the third rib. in original only show as whereas the they In the points. The explanation is that these sharp speaking chest muscles transmit the voice vibrations to the transmitter, thus points when they made contact with the ¡ NIiU111111.1Íill plate blackened the latter at those points, enabling telephone conversation to he car- made they, of ried on comfortably between the two oc- and when the print was cupants of the aeroplane. The course, appeared in white. It will be sect microphone that the electrical spark reproduces every is thus not placed before the mouth. detail of the picture down to the most The telephone receivers and transmitters minute detail. are connected by flexible cords', which Half -tone cuts were tried but without terminate in a small plug. When the aviator obtaining results for the reason that the or passenger takes a seat the p'uc is in- multitude of points which make printing possible were too fine and too near to- gether and the resulting picture therefore appeared simply as a blur.

NEW TALKING MACHINE UTIL IZES COMPRESSED AIR AMPLIFIER. Fig. i. New Talking Machine with Com- pressed Air Amplifier.

style operated by a spring motor; but of course it is readily fitted with an electric motor drive. The second illustration shows the latest MOTOR- 80550 model Vic :rola. equipped with electric MOTOR - BOARD motor drive. This machine has no connec- SUPPORT tion with the one aforementioned, known MOTOR - MOTOR - as the Auxetophone. A very neat and BOAR O BOARO BEARING BEARING readily accessib :e method of mounting the MOTOR drive Vic - CORO SWITCH electric .motor for the standard BLOCK is Fig. 2. CORO trola observed from the sketch, TERMINAL SWITCH CORO The top table- board, containing the record holder or turntable, etc., swings on pivots. as observed, so that the motor and its speed Fig. z. Compact Electric Drive for Victrolas. governor, etc., ' become at once accessible for re¢airs, oiling and o :her attention by A new talking machine, which is known simply pushing a button. as the "Auxetophone" and constitu ing one of the well -known "Victor" line, is shown NEW TELEPHONE SET FOR Aviator with Aero- Phone, Talking Through in our il'.ustration herewith at Fig 1. AVIATORS. ills Chest. As at present supplied, the Auxe ophone Our two illustrations herewith show a constitutes an amplifying phonograph. It new stele telephone set, known as the s rted in a jack mounted on the framework utilizes regular disc records. the ame as "Aero- Phone," and particu'arly designed of the aeroplane. The only battery current any talking machine of the "Vic- requ.red is that furnished by tor" type, and the sounds as given three regular dry cells, which will forth from the records and provide continuous service for 11R) through the regular stylus needle hours 1v:thort any appreciable on the phonograph arm are caused toss of transmis-ion quality. to interact on a special air valve This perfected telephone set for hooked up with a compressed air aeroplane use is of great inter- tank, as illustration shows. est, particularly for military aero- A compressed -a'r blower is nautical applications. driven by an electric motor, as perceived, and the machine is BRONX RADIO CLUB. equipped either for direct or al- The club is composed of 11 en- ternating current, as the service thusiastic members. most of may require. tvhoin have stations of their own. The motor is directly con- Those wishing to further their nected to the blower, which fur- knowledge of the subject are in- nishes air for the pneumatic structed by the more advanced sound -box, in which the volume members. of the sound is augmented or Officers are as follows: M. amplified. An oil condenser is Haber, president; H. Berlin, vice- mounted on top of the blower, as president ; L. Brodie. secretary; shown, which is connected by a The Aero -Phone in Use. A. Richter, treasurer; J. Smith, flexible tube to an air -pressure business manager. equalizirg tank. A flexible tube connects to and intended for the use of aviators. Its Communications from other clubs and the top of the tank and leads to a filter. express purpose is to permit the aviator individuals should be addressed to L. Front the filter another tube leads off to the and his mechanician or passenger to talk to Broc:ie, secretary, 13?2 Boston Road, taper-arm equipment, which includes the each other freely without being in any way Bronx, New York.

A www.americanradiohistory.com 2116 THE ELECTRICAL EXPERIMENTER October, 1915 Electricity and the Modern Automobile Torpedo By Samuel Cohen AMONG the most ingenious weapons roscope herewith shown, is entirely driven With a "fixed rudder" or steering gear on of modern warfare is by l the automobile electricity, supplied by a small same, which shall cause this weapon to ab- torpedo, a cigar- shaped shell con- turbo- dynamo set. The turbine itself is solutely maintain its natural course along structed entirely of steel, with an electro- operated by compressed air from the air a straight line, as was previously intended mechanical brain and carrying a high - flasks 6. This electrically operated gy- when discharging same. explosive guncotton charge. roscope consists of an alternating current Therefore when the torpedo shell is de- This self -propelling demon is shown induction motor, with its rotor and stator flected from its course, even to a slight at Fig. 1 with its clever devices for 12, while 13 is a gimbal ring. The gyro- degree, by tidal or wave currents, etc, it steering and diving. It measures 24 feet scope wheel acts upon a small crank lever will be maintained in practically a dead long and 21 inches in diameter, with a 15, which is connected to the control lever straight course by the correcting action of weight of one ton. This modern fighting 1C, operating the vertical rudders 21. the electrically driven gyroscope.

2 AIR FLASK OR RESERVOIR AR TURBI"L

T AIL AIA PIPE . 21. fn _ / f _AISIONINNI 4.'::42_ , la 1 sArtzti ?1ty i.,ll 21 fl 1® \4 1 .I '1112 TURBO-4CACRATOR - ,) EtrCtplrt FOR 6Y;5r'rl 9 X'd CURRENT I 4YROSCO?[ ' WAR RE _5

Fig. I. Semi -Sectional View of Latest Type Automobile Torpedo. (C) Experimenter Pub. Co.

machine consists of three parts, viz , a As is well known, a gyroscope will al- The rapidly revolving gyroscope ele- War Head, carrying 250 pounds of high ways attempt to maintain its center of ment 12 will, as seen from the foregoing explosive; the central Flask, charged with gravity with respect to a certain point or description, tend to rotate from in the same compressed air at 2,250 pounds per square angle. That is to say, if we have a wheel axial plane as at the moment previous to inch, and an after -body or Tail, in which of any type revolving at very high speed the deviation of the torpedo's true course. the propelling and controlling mechanisms in a certain position, with respect to its Hence the gyroscope will swing about, so are enclosed. axis of rotation, then any effort to change as to maintain its original plane of rota- The "war- head" (1), Fig. 1, differs from the plane of this wheel, in so far as its tion, even though the hull of the torpedo the "practice-head" and is used only in rotation is concerned, will be found to may be pointing several degrees off its true actual fighting. It is loaded with a charge cause considerable effort necessary in or- course at the moment due to interfering of guncotton (2) containing 25 per cent. moisture. At 4 is the detonating charge, which is fired by the plunger or striking rod 3. A safety pin is pro- vided at the end of the plunger, as de- picted, this being used for safety when loading the torpedo in the firing tube. The central flask or air reservoir 6 (Fig. 1) is con- nected to the tur- bine through t h e superheater 8. This turbine is connected to a reducer gear 9 and then to the pro- p e l l e r shaft 10 which operates the 22. Thesll eare 2o- View Above Portrays Appearance of "Wake,' tated in opposite or Path, Through Water Taken by the Torpedo di- as It Skims Over the Water at q0 Knots an rections. The power developed Hour. by the Photo in Upper Left -Hand Corner Shows Modern turbine is 110- horse- Type Torpedo Being Discharged from Tor- power and the shaft pedo Boat. The Cloud Results from the Com- runs at 1,200 pressed Air Exhausting from the Torpedo. RPM., enabling the Lower Picture Depicts the Massive Columns missile of Water Resulting from Exploding Two Mod- to travel at an in the rate ern Torpedoes by Italian Torpedo Boat of 35 to 40 rnoto Oy ram inumpson the Mediterranean. knots, with an ex- treme range of 10,000 yards. der to accompl.sh this change. Thus, the water currents, etc. It is in the "Tail" that the brain of the gyroscopic principle is brought into play in When the rotating gyroscope element 12 weapon is installed, and the little electric order to keep the modern automobile tor- makes this swing about its plane it tvill gyroscope 16, which a few years ago was pedo in a true course. As becomes evi- carry the gimbal ring 13 with it. On this considered a toy, steers the torpedo to the dent, and especially when the water is very ring is a trigger release cam which, as the right or to the left. It is a'i almost human rough, it is practically impossible to dis- ring 13 moves around, allows the spring - pilot and steersman, so to speak. The gy- charge one of these high -speed torpedoes actuated cam rod 14 to slide forward.

www.americanradiohistory.com October, 1915 THE ELECTRICAL EXPERIMENTER 267

When this cam rod slides forward, as de- TENNESSEE TRI -STATE FAIR TO MODERN APPLICATIONS OF THE scribed, it ejects or pushes upward the rud- HAVE RADIO. LOUD SPEAKING TELEPHONE. der control trigger 15. When the tor- Visitors to the Tri -State fair at The "loud talker," or more properly the pedo has been thus automatically brought Memphis, Tenn., who want to send their loud -speaking telephone, is now being ex- back into its true course it will be seen that regards to the Kaiser or Kitchener, can tensively employed in places where the the gyroscope will then have its gimbal step into a wireless office, write out the ordinary telephone cannot be used, and ring 13 brought back into its normal plane, message, pay a fee of a few dollars a the illustrations herewith presented depict and in so doing it will, of course, reset the word, and let 'er zip. some novel applications. Fig. 1 portrays cam rod 14 to its normal position, and This became known recently when Frank a stenographer taking dictation from her so on. Fuller, secretary of the fair association employer by means of these loud talkers. The depth of the torpedo is regulated -tated that the Tri -State Wireless Asso- The transmitter is placed on the left of the apparatus. as seen, and is utilized in ordinary talking. as for instance, when the stenographer desires repetition of a sen- tence, etc. This method of dictating is very effi- cacious as a time saver, and eliminates the use of a buzzer or bell in calling the stenographer. Fig, 2 illustrates a field -type loud talker employed in high- tension line work, where the linemen need to keep in constant touch with the switchboard operator at the power station. This instrument is constructed en- tirely of an insulating material, so that the high voltage of the line does not enter the Fig. 2. Actual Photograph of Bass- Leavitt Automobile Torpedo. instrument in proximity to the person talk- ing. The square- shaped horn leads to the by a depth -control mechanism 17. It con- elation was going to install a service receiver, and the long, round tube in the sists of a metallic diaphragm 18, actuating branch at the fair grounds. center is connected to the microphone lever 19 and in turn operating the rudders An aerial will be erected and apparatus transmitter. The small handles in front 20. This device is usually "set" for 15 with sufficient power to give the visitors are the two switches operating the calling feet below the surface of the water, so that an idea of what a real wireless station is, and talking circuits. when the tube is fired it will go below this will be installed. mark, but the diaphragm immediately is actuated by the greater pressure of the them in operation. The fans are a spe- Top Photo illus. water and in turn lowers the rudders 20, trates Steno- which raises the torpedo to its proper level. cial type made up for grapher Tak- A new method of controlling the depth the purpose, running ing Dictation at 1110 revolutions per From New of torpedo tubes has been recently tried Style "Loud - which employs electricity. This is kept minute and with a Talking" Tele- the very slight pitched phone. Lower secret at present and information on Left Photo details of this system is unavailable now blade so there is prac- Portrays High The torpedoes are launched from a dis- tically no breeze de- V o l t a g e impulse of veloped by them. Th_ T r ansmission charging tube by an charge Line Tele- compressed air. As slon as the torpedo is blades have a sweep phone Set launched the trigger 11, at the center of of 90 inches. The With Loud - is disengages the purpose of the fan is Speaking Re- the flask, released, which p roducer. high pressure valve of the reservoir and simply to throw a Lower Right the turbine, and in turn operates the two moving shadow on View is That soon as the meats, fruits and of Small and propellers. As the torpedo strikes E f fi c i e n t the water it submerges to the proper depth vegetables to scare Hand Micro- and rushes with a mad pace straight to its the flies away. phone With Cut -Out But- target. These fang have the ton. One of the latest 21 -inch diameter auto- advantage over an mobile torpedoes of the Bliss- Leavitt type ordinary ceiling fan is shown in Fig. 2. This complicated ma- wish a high speed, in chine costs nearly $6.000 to build. Uncle that the ordinary fan Sam is now expending large sums of causes meats to be- money in building these weapons, and the come black and also Newport naval factory is turning out hastens the decay of about 100 of them annually. These fight- fruits and vegetables. ing sea machines have proven a great suc- while this new design cess. as shown in the present Europeal gives very little breeze conflict. and dues not affect NEW FLY CHASING CEILING FAN. them. Flies are also The photograph portrays a new fly -chas- in evidence where the

ordinary fan is used. A miniature hand -style transmitter for but the shadow effect general use is shown in Fig. 3. It is of the scares the flies and has ordinary carbon -grain type and it measures completely solved the 61/4 inches long by 21/4 inches and weighs problem for market - only four ounces. This transmitter can be house people. placed in the regular telephone A The Shadow, Not the Breeze, Chases the Flies. circuit. Thus a little science small push-button is placed near the end, ing electric ceiling fan recently installed in added to practise has apparently solved a as depicted, and is used for calling pur- the Reading Terminal Market, Philadel- very troublesome problem. poses. These instruments have been de- phia, Pa., and at present there are 42 of veloped by the Stentor Electric Co.

www.americanradiohistory.com 268 THE ELECTRICAL EXPERIMENTER October, 1915 Sayville Once More An Attack on the Electrical Experimenter two letters reproduced herewith Atlantic Communication Co., Your assertion that "The Electrical Ex- no comment. The one illus- New York City. perimenter is joining some of the daily THEHEtrates the German viewpoint, the Attention Dr. 6, G. Frank. newspapers 'in the contemptible attempt to other the American. We leave it to our Dear Sir: - cast suspicion upon Sayville and, further, readers to decide which is the correct one. The writer was indeed surprised to re- that no single instance of a dishonorable Dr. K. G. Frank, as is well known, is the ceive yòur communication of August 17. act can be proved. but also that there has prevent executive head of the Sayville He is at a loss to understand how you never been any charge of such act made by wireless station. On August 17 the Provi- could possibly misconstrue the true mean- any official of the United States Govern- dence Journal lard before the U. S. Neu- ing of his editorial in view of the fact ment," is as perverted as it is unfounded. trality Board in Washington eight formal that at the time it was published Sayville its tone is also resented by the writer. The charges. One of these charges was that nad already been taken over by the Govern- Electrical Experimenter certainly never at- Dr. K. G. Frank is the head in the United ment. What the editorial meant to con- tempted to cast suspicion upon Sayville, States of what is known in Berlin as an vey was that even though the Government but it has shown that the station can, and information Bureau (secret service). had taken over Sayville, it was not at all perhaps has been used to convey unneutral The letters follow: certain that messages pregnant with un- messages, though not necessarily with the ATLANTIC COMMUNICATION CO. neutral information, yet harmless on their knowledge of the management or its oper- (Telefunken System of Wireless face, could not be sent in spite of all cen- ators. Telegraphy) sorship. The imaginary case of the mes- At the same time the writer desires to sage from the 'Adriatic" was cited as an voice his opinion that there is sufficient cir- 47 -49 West Street, illustration. Anyone by paying the usual cumstantial evidence at hand to lead any- The Experimenter Publishing Co., tolls can even now send such a message. one who wishes to view the matter in its Attention Mr. II. Gerntack, Editor. The management or the operators at the true light to believe that the management Dear Sir: -With regret and surprise I Sayville station obviously need not neces- of the Sayville station probably had some have read your editorial in No. 28 of The sarily have cognizance that the message is knowledge of the real purport of the many Electrical Experimenter on "Sayv Ile." an unneutral one. "irregular" messages sent over the Atlantic Accor :'ing to lily knowledge your paper That the writer's viewpoint was correct by Sayville before the station was finally is the only technical paper which joins tome is best shown by the announcement ofSec- taken over by the United States Govern- of the daily newspapers in the contemptible r tart' of the Navy Daniels under date of ment attempt to cast suspicion upon Sayville. August 18, "that as a result of the demon- The slur contained in your last para- One would at least expect that your paper stration that unneutral messages could be graph is best. met by bringing to your at- would take cogs zance of the fact [:sat not sent through the Sayville station he had is- tention the fact that The Electrical Experi- only no single instance of an unneutral act sued orders that in all cases where the. menter to -day is considered an authority can be proved, but also that there has never Government experts were in doubt about on wireless matters in this country. As been any charge of such act made by any any message presented for sending it such it is its duty to publish any matter of official of the United State. Government. should be referred to Washington for judg- interest to the wireless world. It will dis- The standard of the technical and ment." tinguish itself in the future by continuing scientific press in this country is, fortu- As to the second paragraph in your let= to do so. It will also continue voicing its nately, so high that I ani convinced your ter your attention is directed to page 210, opinion especially at times when the wel- paper will remain the only one which dis- September issue of The Electrical Experi- fare of this country is concerned. tinguishes itself in such manner. menter. It gives facts with which you are Very truly yours, Very truly yours, doubtless familiar. These facts disclose The Experimenter Publishing Co. (Signed) Dr. K. G. Frank. o'e of the main reasons why Sayville was (Signed) H. GERNSBACK, Editor. Nere' Yon., 1V. Y., August lî. 1915. taken over by our Government. New York, August 30, 1915. $2,500.00 Edison Day Contest for Boys and Girls Edison. the Wizard of Menlo Park, tribute, then go in to "win." Make a list lamps. This credits you with (4x40) 160 whose name is mentioned with reverence of people and visit them. Learn all you can points. by all for his inventive ability, has always about the prices and different sizes of 8. After October 21 the lighting corn - been liked by his fellow investigators. It lamps, so as to be able to talk intelligently pany or Edison agent turns in all the cards was his invention of the incandescent lamp on the subject. to the Edison Lamp Works of the General 36 years ago that will indirectly cause him Instruct the people you visit that they Electric Company, Harrison, N. J. to be equally liked by thousands of boys are to hand in your card with their order 9. The cards are sorted and the boy or and girls throughout the country. for lamps, so you can see it is necessary to girl whose naine appears on cards totaling From the crude little carbon filament get into action before another boy or girl the greatest number of watts or points gets lamp that made its initial bow to the world can get in ahead of you. Don't distribute first prize, the next largest the second prize on October 21, 1879, it has rapidly advanced your cards before the 21st of September. and so on down. to the modern high efficiency tungsten fila- although you can obtain the cards before 10. In case of a tie by two or more con- ment lamp of to -day known universally as that date. testants, each one will receive the prize. the Alasda. 11. The prizes will be distributed by the The manufacturers Any further details are explained by the of the modern form Conditions: Edison Lamp Works of the General Elec- of this lamp are planning a unique adver- tric Company as soon as the cards are tising campaign that will enable numerous 1. You must be under 18 years of age. counted and the winners determined. children to win, in all, $2;ïon,uu wort[ of 2. You must live in or near a town 12. No prize will be awarded to any em- valuable prizes. having electric light. ploye of the General Electric Company, These lamps are so saving of current 3. You must get a number of cards lamp agent or lighting company. and give such satisfying results that not to from the local lighting company or agent You have the plan before you, now mob- use them is a loss of money to the store- for Edison Mazda lamps. ' ilize your forces, bring up your artillery, keepers and the householder: therefore, to 4. You must sign your name and ad- for there's an Indian motorcycle for first introduce this lamp more widely this special dre-s to all the cards. prize for the boys. and an Edison diamond campaign was organized. It is understood, 5. You must distribute the cards to disc Phonograph as first prize for the girls. of course. that you must live in a town users of electric light in homes, stores. The other prizes for boys run all the way having electric lights, but if you live suffi- factories, etc., from September 21 to from a row -boat motor to baseballs and ciently near a city you may enter the con- October 21, 1915. gloves, including canoes, watches, boxing test. 6. The cards will be returned to the gloves, rifles; and girls' prizes include The plan outlined is as follows: You lighting company or Edison agents as or- mandolins, wrist watches, electric chafing obtain cards from the local agent for der; for Edison Mazda lamps at any time dish, toasters, desk sets, fountain pens. A Edison Mazda lamps and after signing between September 21 and October 21, host of valuable articles, all told, and 2,000 your name in the proper space thereon you 1915. flash -lights are to be given away. distribute them to persons whom you think 7. A watt is a point. For example: It will require some work, but you will can be induced to use the lamps. You get A card with your name on is turned in as enjoy it as much as the premium yoti will as many cards as you think you can dis- an order for four 40 -watt Edison Mazda win.

www.americanradiohistory.com October, 1915 THE ELECTRICAL EXPERIMENTER 269

THE.._ _ D_ '

L_T.114:1 . . . . Construction of an Inductive Tuner. By Milton B. Sleeper IN the design of this tuner are incor- sized. Get one 7%x3 9/16x4 inches and This keeps the wire tight without rubbing porated all the advantages of the larger, one 7'x3'/tx3'/- inches. First cut them the insulation. Hold the coil in your lap, more awkward designs, in a compact 3' inches long with a hacksaw, then finish facing away from the spool of wire. Turn enclosed form, having a centra.'iaed con - the tubes to the proper length with sand- the coil with one hand and guide the wire rol for the sharpest tuning by simple ad- paper on a large block. As the larger coil with the other. Do not turn the wire ustments. Wi:h the regulation size an- is too small inside, it must be worked out around the core, as this makes kinks. with sand paper or a The taps are made in the following coarse file to the required order : beginning of winding, end of first diameter. Keep the walls turn, end of second tur.i, end of third, 7, uniform in thickness. One - 9, 12, 16, 20, 24, 28, 32, 36, 4n, 44, 4R, 52, sixteenth of an inch must 51;, 60, 64, 68, 72, 76, 9o, izl, 99, 92, 96, 100, he taken from the outside 104, 108, 112, 116, 120. (1) Fig. G shows diameter of the smaller the method of making taps. The taps core. This is to allow should be made in a straight line down the room enough for them to coil ; however, the first ones should be slide. After the cores are staggered a little, so the bare wires will brought to size, rub them not come in contact with each other. Be smooth with fine sand careful in scraping the insulation where the paper. Do not shellac or taps are twisted (see Fig. 6) not to cut in any way moisten or the wire. By scraping the wire in this heat the tubes, as this way losses from taps are minimized. Leave causes them to expand. a good 6 inches for connections to the After two or three weeks switch. It is well to run a little sealing fq. / they shrink again, and if wax over the wire where the taps are the coils are wound the made. When the winding is complete Fig. r. Front View of Completed Coupler. wire loosens. One -half fasten the end through two holes as be- pound of No. 24 double fore, leaving enough for connection. Next, tenna it will bring in signals over 1,200 silk -covered wire is required for the cut up four strips of thin cloth, 4 inches meters; the largest range any tuner can primary. by 4i inch, and soak them in fairly thick have without being affected by dead -end Primary winding. -Begin at the left - shellac. Then lay them lengthwise on the losses. Fig. 1 shows the unique tuning con- hand end to wind. To start the winding, winding, 90 degrees apart. Cut off the trol. On the large 30 -point switch every make two small holes one -sixteenth of an ends of the cloth even with the ends of fourth turn of the primary is tapped, while inch from the end of the tube. Put the the tube; do not turn them under. This with the compensator handle, in the middle of the other, three turns can be added, one at a time. This gives the sharpest tuning possible in the simplest way. Taps from the secondary, 10 in number, are brought to the right hand switch. The coupling, while sliding, is adjusted by rotating the handle 65 degrees, giving to thi% type the advantage of the variometer. Although it has ample variation of coupling, it is a very compact instrument. To keep the coils from being affected by the atmos- phere, and to protect the working parts from dust it is enclosed, except for the controls. These are closely grouped on the front of the case. Tuning can be done many times quicker, with less effort than is required with the ordinary type, where the primary switch or slider is at one end, the secondary switch at the other, while a movement of 5 or 6 inches is required to vary the coupling. At the conclusion of the article is an en- tire list of parts, with their size, number, material, etc. Using this list, all the rough materials should be bought before any actual work is done. Then do not put any pieces together until they are all completed. Follow the drawings closely, otherwise the pieces will not fit. Coils. Cores. -These are shown sectionally in Fig. 2. While ordinary mailing tubes can be Fig. z. Sidewise Sectional View of Coupler, Showing Primary and Secondary Coils. used for the cores by changing the diameter end of the wire from the outside into one will keep the wire tight without shellack- of the inside pieces, it is not at all advisable ; hole and bring it out the other, leaving the ing it all over. Inside the core at the bot- the drawings are for tubes made by Beetle loose end 6 inches long for connection. It tom, 90 degrees from the line of taps, glue & Maclean. As they are not made just is best to run the wire over a series of the two guides 1/16 cf an inch apart (Figs. the right size, they must be purchased over- spools on spikes pounded into a flat board 2 and 3, which will keep the secondary

www.americanradiohistory.com 270 THE ELECTRICAL EXPERIMENTER IllOctober. 1915

from turning. Be careful they are per- other parts fit in it properly. Put the The nut, N% In hold the compensator con- fectly parallel with the axis of the core. bushings in from the outside; then it will tact must not be screwed too far down or Secondary. -One- fourth pound of N. not matter if the wood is chipped in forc- the compensator handle will bind. Get all ing the bushings into the the switches fastened to the front and in holes. The staple X in working order before fastening any taps. Fig. 2 is 11/4 inches long. Secondary Switch. Drive it into the end -piece Fig. 5 gives the dimensions of this switch. before the case is as- This contact is also made with three thick- sembled. An excellent nesses of brass strip. The connection is finish can be made with a made by a copper strip soldered to the dark mahogany stain. spring on the back side. Although it is When it is perfectly dry roc necessary, it is best to knurl and bevel apply three coats of thin the edges of the handles as Fig. 3 shows. white shellac and rub it (To be concluded.) down with finest sand- paper covered with lin- TREATMENT FOR SULPHATED i seed oil. This gives a STORAGE BATTERY PLATES. dual, durable polish. The A great many experimenters have stor- rubber feet on the bottom age battery plates on their hands from time prevent the case from to time which have become badly sulphated scratching the table and as indicated by a tenacious white coating, keep the case up to allow which gathers on the surface of the plates. for the overhang of the Of course this renders them practically in- front. active so far as the regular function of the Primary Switch. storage battery is concerned. The parts of this switch A method not generally known is de- must be turned out ex- scribed below for the treatment of such Fig. Assembly 3. of Primary and Secondary Coils in Cabinet. actly. Fig. 4 gives the de- sulphated plates, but great care should be 26 double silk -covered wire is required for tails. (1) shows the underside of the exercised in using this method in the the secondary coil. The taps (see (2) Fig. handle; (2) is a section through the thorough washing of the plates after the 6) are made differently. Instead of com- switch; (3) is the back side of the switch, bath below mentioned has been utilized. ing from the outside, they must come from showing the compensator. The large Before replacing the plates in the bat- the inside of the core. Beginning 1 /16 of switch contact is made of three an inch from the end of the secondary thicknesses of No. 30 spring core, mark off 3/10 of an inch 10 times. brass. This gives a better con- At these points make holes just large tact than can be had with a single piece. It is fastened to the plate by a screw threaded into the handle. The plate is held to the center piece (D ) by a little drop of solder. Con- nection is made by soldering á strip of copper to the spring (A) under the centerpiece. In this way connection is made to the switch -points through the switch contact, plate, cen- terpiece and spring. The handle must fit tightly over Fig. 6. "Tap" Lead Details. the end of (D) to keep it from slipping. The insulating tube (C) is forced into (D), enough to slip the wire. There are 14 but the compensator rod (B) turns of wire between these holes. If the turn in the tube. holes made is tightly must easily are right and the wire The four switch -points for Fig. g. Details of Secondary Switch. wound this will be just the right distance. the compensator are made of round -head tery they should be washed 12 to 15 times be least 10 inches long. These taps must at S -32 screws, their heads turned down 3/16 in changes Put thin strips of cloth with shellac on different of water or placed for inch in diameter and 1/16 inch thick, then a considerable period under a running this winding also. lugs for the taps are fastened under the water spigot, or otherwise any remaining Cabinet Details. heads of the screws. To keep the com- ammonium acetate in the plates would The dimensions for the case are given pensator switch contact from 'turning off cause them to disintegrate when the bat- tery was again put in service. This special sulphation treatment "bath" is made up of about one -half pound of ammonium acetate, dissolved in one quart of water and put in an earthenware jar. The lead storage battery plates requiring treatment are immersed in this solution for about one -half hour, and they should be kept hot during this period by a gentle flame placed under the jar. The plates will now become freed from the sulphate coating, and they are then afterward re- moved from the jar and very thoroughly washed as previously explained. The am- monium acetate can be purchased at any drug store or chemists' supply house and is fairly cheap. A larger bath solution may be made up, of course, following the above proportions. HOW TO CLEAN BRASS. Brass instruments or parts thereof that have become tarnished from exposure to air may be cleaned in the following man- ner: Boil for a few minutes in a solution of one ounce of alum to every part of Fig. 4. Parts Making Up "Primary" Switch of Coupler. water. Then polish with any kind of brass in Figs. 2 and 3 and in the list of parts. the points it is necessary to put in a stop- polish, or even a dry cloth will do. This Each piece must be perfectly accurate or ping pin at each side. The spring (A) will remove tarnish from all crevices the case will not look well nor will the must be strong to hold the switch together. where other means have failed. S. C. V. www.americanradiohistory.com October, 1915 THE ELECTRICAL EXPERIMENTER 271

ELECTRIC IGNITION SCHEME with the wipe spring and the spark is cut particular means employed to earth one FOR GAS RANGES. uff. The secondary 1-1. T. switch still has end of this winding, say at f. The electrical experimenter may put to be used for the different burners. A convenient arrangement is shown in some of his ideas to a good purpose in rig- At Fig. 2 is shown a common system the accompanying drawing illustrating a ging up an electric ignition system on the used in shops and readily adaptable, of diagrammatic view of the complete ap- kitchen gas range. Two methods are sug- course, to die kitchen gas range, whereby paratus, including a Bosch high -tension a common "inductance" ur "kick" coil is maenetu. utilized in series with a battery. The spark The one terminal c= of the coil is con- produced in this way is a "wipe" spark, as it is commonly termed. To create the spark a metal -tipped handle T is used to make and break the circuit against a spark- ing wire or point over one of the holes in the gas burner, as at S S. This wire S may be a piece of steel or German silver stock. In operation the gas is turned on and directly after it, the igniter handle T is passed across the spark point S, thereby producing a "wipe" spark, which ignites the gas. A battery of four dry cells is Electric Light From High Tension Magnetos. usually sufficient and ordinary bell wire Fig. r. "Jump" Spark Applied to Gas Range. may be used in hooking up the circuits be- netted to the terminal d, which is in con- tween the battery, stove and coil. nection with the primary winding of the gested in the drawings herewith, at Figs. Inductance spark coils may be purchased magneto, and is provided for use in con- 1, 2 and 3. cheaply at any electrical supply store and junction with a switch g, whereby the At Fig. 1 is indicated the connections for are commonly known as "gas lighting ignition may be cut out by earthing the utilizing a small jump spark coil of about coils." It also may be made up from an primary current and preventing an ef- 1 -inch rating, together with battery and iron wire core about 0 inches long by 1 fective portion of it passing through the primary switch, and also the specially in- inch in diameter. This core is provided contact breaker. The other terminal c' is sulated secondary switch. The secondary connected to one of the terminals of the wiring for the jump spark circuit to the lamp; the other terminal of which is burners should be made with high tension "earthed" at f. A switch g may be in- or automobile engine cable. Ordinary wire serted in the circuit at any convenient may be used, as sketch shows, by Zeldin: place between the coil c and earth, where- this wire through porcelain tubes suitably by the lamp may be put into and out of secured to the top of the stove. Two o_ action. more burners may be provided with spark The inventors have subjected this de- circuits by using two or more switch points vice to a test with a one and two- cylinder on the high- tension switch A. This switch motor -cycle engine, employing a Bosch should have good spacing between the magneto for ignition purposes, using a points and the blade on same should be metallic filament lamp of 3.5 volts. Their about 4 inches long. It should be provided experiments have shown that excellent re- with a hard rubber stem and handle, so gilts can be obtained from an iron core that the hand will be several inches away having a length of about 4 to 5 inches and when manipulating same. 1 diameter of 5/1G inches, wound with As evidenced from diagram, Fig. 1, both approximately 517 turns of double cotton - the primary and secondary switches have covered copper wire No. 24 and efficient- to be manipulated when the gas is turned Fig 3. Detai o Automatic Gas Sto e gniter ly insulated between the windings. The on in the burner. The spark jumps from Attachment. apparatus may be applied to other suitable the wire (at the end of the porcelain tube), with magnetos in a substantially similar man- which is placed over one of the small holes two wooden discs at the ends about ner. in the burner, to the burner itself. One 31/2 inches in diameter and the core is cov- side of the secondary winding of the coil ered with several layers of heavy paper. Over this is 8 10 layers 14 is grounded, at G, to the stove frame. wound to of No. A POWERFUL ELECTRO- MAGNET It is very easy to rig up an automatic cotton -covered or enameled copper magnet FOR BATTERIES. primary switching stunt for this outfit wire. This coil will serve for all kinds o: A great many electrical experimenters using a as Fig. gas ignition, utilizing the "wipe" spark jump spark coil, shown at principle. by 3 in detail. The one primary wire is joined Contributed JOHN GALLAGHER. Pound wrot.0/ iron to the iron frame of the stove and the ? leads joined other primary wire connects to an insulated copper or brass wipe spring, as observed. A metal pin. such as a machine screw. ELECTRIC LIGHT FROM HIGH tapped into the knob of the gas valve han- TENSION MAGNETOS. \Vith the advent of magnetos for the D purposes of ignition in internal combus- mope/ coi/ tion engines, the thoughts of motorcycle and automobile manufactures turned to the possibility of introducing in a satis- ///7 /ribs factory manner, some means whereby the electric current generated by the magneto. could be utilized for illumination, as well as for ignition. Accordingly. various devices to effect this happy combination have been given birth, and one of them because of its simplicity of construction and operation, is worthy of consideration. The device is of recent invention and is the subject of an English patent. The gi Fig. z. "Wipe" Spark Applied to Kitchen Gas principle the inventors have worked upon Range. is that of transforming the voltage at the fi/A I/nOJ/h primary terminals of the magneto down Armo /ore tro die makes contact through the first part to that of the lamp to be used. The in- of its swing with the wipe spring. Thus vention accordingly consists of a resist- the primary circuit is closed while the gas ance in the form of an iron core choking ^ fig % valve is being first turned open and the coil, c together with an incandescent elec- Fig. t. Parts of Powerful Battery Magnet. secondary spark from the coil jumps at tric lamp e (preferably of the metallic the burner, igniting the gas. As the valve filament type) connected between the prim- often wish to have a good strong electro- handle is opened further it breaks contact ary winding d of the magneto and the magnet suitable for excitation on a few

www.americanradiohistory.com 272 THE ELECTRICAL EXPERIMENTER October, 1915 battery cells, such as dry cells, for instance. HOW TO BUILD AN ELECTRIC INSPECTING EGGS WITH X -RAYS. The following describes the detailed con- FURNACE FOR LABORA- Eggs are now being examined by X -rays, struction of such a magnet. This data is TORY USE. and this new m.thod is said to be á very from an instrument that has actually been Following is a description of an inex- good one. built and, when operated on 10 ordinary pensive, but practical, experimental electric A special darkened room is installed in dry cells, such as the "Columbia," it devel- furnace. the quarters wher!the eggs arrive and the oped a lifting power of 50 pounds, the The materials necessary are two fire apparatus consists of a closed lantern con- voltage being 15 and the current in amperes bricks ( stich as those used in building fire- taining an X -ray tube. In the front of the 09:5. This lifting effort was attained by proof structures), two carbon rods, and tying the load to the center of the iron two pieces of No. 10 gauge steel wire, armature A. about 25 inches long, to be used in holding II u111 II1III1II_ II IIhJI I,l ' IIIIIII " the fire bricks together. Grind or file a groove in A and B, as t-t;mpI11II!!I. ,'! Igg!I1 p pp ylllql!II!111pllll!lqplII! shown in Fig. 2, so that when the bricks ,rire /eadha/es are placed in position the carbon rods to IIIV1pl41 be inserted will slide easily back and forth. /obi brr/ I 1 over On one brick, used for the base of the 'IIIIII 1Vi b furnace, chisel a groove in the middle, two inches in diameter, so that it forms a semi- ; circle (see Fig. 1). This hole will be used ? Fibre cod rheU- ó'iÁ in une /o vver,rao making observations of the reactions /d core that place the insertion \ take and for and I r.i extraction of materials to be melted, which 11 í I iII I ) q lr / ,iÌ I are placed in the grooved chamber be- tween the ends of the carbon rods. F :g. 2. Making Magnet Coil Spools. This simple furnace when properly as- . I Im III 1111CI 'l 1 sembled and c.:nnected to 110 -volt lighting To begin with, a piece of wrought iron X Rays Used to Test Eggs. bar should be obtained at the hardware current, as illustrated in Fig. 3, will de- store or from a blacksmith, and it should velop such an intense heat that some of lant..rn is a small opening.about the size of have a diameter of 9 -16 inch. Its length the following refractory subs':ances can be an egg, so that the rays can pass through should be sufficient to allow of bending to made: Calcium carbide (used for gener- the egg. The rays throw a shadow of the the dimensions shown in the sketch Fig. 1 egg upon a fluoroscop: screen placed in at B. Another short piece of square front. Fresh eggs are seen to be quite clear, wrought iron bar, A. Fig. 1. is required but any defects are shown up as spots ap- also to form the armature. One side of the pearing on the screen. Such eggs are put armature bar, tha: which is to be in contact in the second class, but if the spots are too with the pole fàces of the magnet. must large they are rejected. It is well to have a be filed off smooth and flat for about 1 inch sheet lead front in the box A to screen off at both ends to insure a good magnetic the rays not necessary in inspecting the egg. circuit between these two parts of the iron circuit. UNIQUE COUPLER SWITCH. After the piece of 9 -10 inch round iron The multi -point switch, shown in sketch bar has been bent to a "U" shape, as indi- herewith, provides a large number of cated in Fig. 1, the two pole contact faces switch points in a small space. This is must be filed up smooth and flat with re- accomplished by arranging a sliding contact spect to each other. Also to increase the shoe of thin copper or brass, as perceived, magnetic density at the pole faces, and and as the switch arm is rotated this mov- thereby gaining a greater pull, these pole able or sliding contact shoe gradually face areas are reduced as shown, so that works outward from the center of the they have but 1/2 inch diameter. This can switch. at the same time making contact be accomplished very easily with a file. with each successive switch point, as will The magnetizing coils are wound on two be apparent. tin spools or bobbins, made after the fash- A fiber stop may be mounted, as shown, ion illustrated at Fig. 2. The end cheeks so as to prevent the switch shoe from mov- of these spools are made of heavy card- ing past the final contact points either way. board or fiber. The tin tubes should be Sample Electric Furnace. These stops are made level with the tops about VA inches long and tit nicely over of the switch points, of course, so that the iron ating acetylene gas), carborundum and the core legs. After making the tubes, con- lever can pass by them, but so as the shoe which can be held together artificial gems. The current can be by a little lamp bank made up of a num- cannot. solder, the end cheeks are placed on them trolled by a of 110 -volt lamps (D. C. is best em- and the ends of the tubes (previously cut ber all way around ployed), as indicated in diagram. A water for about tiA inch deep are used for the cur- bent upward to hold the cheeks on. One rheostat can also be cheek on each rent regulation. Contributed by bobbin should have two 1 -16 ALFRED GWYNNE. tmognef cods magne metallic part of the bobbins, as this would JA J f be liable to cause a "ground." The bobbins are each wound with 14 layers of No. 22 B. & S. single cotton - covered copper magnet wire (this requires e about a% pounds of wire). These layers .I Pole N Pofe are to be placed on evenly. and not wound on any old way, as fewer turns are ob- 11111111111 -- tained on the coils in this way. The start- Bo/ A- ing terminal of the coil is led through the inner hole in the end cheek, while the f9 finishing terminal is brought out through Fig. 3. Hooking Up Magnet Cons tor Proper Polarity. the outer cheek hole previously made for it. The two magnet coils are joined in inch holes drilled through them -one near series at 3A in diagram. In assembling the tube and the other close to the outer the complete electro- magnet the relative edge. These are to lead the coil or wire magnetic polarity of the two poles must Unique Sw tch Enab es Use of Many Contacts terminals through. be observed, and reference to Fig. 3 will in Small Space. When the two bobbins .have been finished make this quite clear. Contributed by E. L. H. thus far they are insulated over the metal The poles of a magnet are termed north portions by wrapping two layers of ordi- and south, depending upon whether or not Fig. 3 A, it is perceived that the current nary notepaper around them. This paper they attract the N. or S. pole of a magnetic must travel around the two magnetizing must fit snugly up against the end cheeks needle, such as in the small compass shown coils in opposite directions to give resultant to prevent the coil wires from touching the in Fig. 3 at B. By looking at the diagram (Continued on Page 302.)

www.americanradiohistory.com October, 1915 THE ELECTRICAL EXPERIMENTER 273

Tufts' College Professor Devises New Wireless Control Scheme ANEW scheme for controlling various condenser is shunted. Very sharp tuning SAYVILLE WIRELESS STATION kinds of mechanical apparatus by is readily accomplished with this new cir- COMPLETED. means of wireless waves properly cuit and static is practically eliminated. The Sayvi;le wireless station, recently developed and propagated from an antenna has been devised by Prof. B. K. Shepard, of Tufts College. Our illustrations show Prof Shepard's apparatus as used in demon- strating his new system of radio control. It is said to be different from that in- volved in the well -known "Hammond" ap- paratus of this character, and also this new arrangement does not make use of any ground or "earth" connection, as is usual with practically all other systems of this type. The first illustration shows the inventor holding his transmitting apparatus, which is quite light, as will be evident. This em- ploys a spark similar to other radio sys- tems and the waves are sent out from the vertical metallic antenna rod and the etheric waves set up are intercepted by the vertical antenna of the receiving set, mounted on a table. By means of this apparatus it is possible to ring bells, start and stop motors, operate semaphore arms, light lamps, steer a min- iature auto, navigate a 7 -foot model boat, fire a cannon, etc. Prof. Shepard is now at work on a wire- less submarine boat destroyer. This ap- paratus, as so far developed. employs no ground connection, as previously men- tioned. and in case a torpedo fitted with this device misses its mark, it can be steered back to the sender, in virtue of the wireless wave control involved in its op- eration. The second illustration shows Prof. Abose: Prof. Shepard operating a miniattire automobile, Shepard Hold- and the little girl in same is his young ing His New daughter, Miss Leonora Shepard. Wireless Con- trol Transmit. tang Set. Re- A NEW AUDION RECEIVING ceiving Set with Various Devices CIRCUIT. Mounted on Herewith is illustrated a n'ew receiving Sw.tchboard. circuit employing two variometers and four variable condensers in connection with an audion detector. With these condens- At ers, having maximum capacity, it was found Shepard'sRight: Prof. that best efficiency can be realized. Each Daughter E n - variometer, as well as condenser, is inde- joys a Ride in the New Radio pendently tuned and a regular audion hook- Controlled Au- up is utilized, as perceived, with the ex- tomobile. N o Ground is Used.

F Photo (C) International News Service HAMPTON, IA., GETS RADIO TIME. taken over by the United States Govern- Hampton will soon be one of the few ment from the Atlantic Communication small cities in Iowa to receive correct time Co., is now completed and is one of the signals by wireless direct from Springfield. largest stations in the world. The fourth Ill., and Arlington, Va. C. H. Haney has of the new reinforced towers has just been had an aerial wire installed extending from finished. This makes a total of 11 towers. the top of the standpipe to the tower of the The new powerful 100 K.W. transmitter court house and thence to the roof of the makes direct communication with Germany Rule block, and wires will lead from there easy. regular and intelligible. to an instrument in his store, enabling him to get the time by wireless direct. For the WIRELESS STATION IN CAMP. ir present he will be able to receive messages A wireless station has been set up by may installed David Meirowitz at S. Melnik's cottage on Imp oved Audion Hook -Up With Variometers only, but later an apparatus for Sharp Tuning. enabling him to send out signals also. Orlando avenue, at Pontoosuc Lake. The aerial has only one wire 200 feet long. ception that across the phones and high- The November issue will eclipse even the After some experimenting very good re- voltage battery a variable, high capacity present one. Don't miss it. sults have been obtained.

www.americanradiohistory.com 274 THE ELECTRICAL EXPERIMENTER October, 1915

A UNIQUE CHEMICAL RADIO AMPLIFIER. Receiving Wireless Messages With Odd Aerials At last an amplifier for the radio ama- THE composite illustration shown on close, even i/2 inch apart, the diameter of tcur, which will boost incoming wireless the opposite page indicates a num- the turns being 11 to 2 feet or even more. messages fifteen hundred times their orig- ber of odd aerials, which may be Iron Fire Escapes on buildings have been inal audibility in strength of signals, has used more or less successfully under cer- used successfully in picking up wireless been devised. tain conditions for the reception, of wire- signals, especially in cities, as seen in Fig. 3. This new amplifier consists of a special less messages, especially in large cities. Another freak aerial, which generally chemical placed between two electrodes The action of these freak aerials is based, works quite well unless the leader pipes which arrangement changes the resistance of course, upon the fact that they are of are grounded through iron water pipe con- by virtue of a diaphragm attracted to an metal, and that also they have a distinct ductors, is that shown at Fig. 4, making use of a Tin Roof on a house. A scheme described in detail in the March, 1914, issue of this magazine is in- dicated at Fig. 5, for the reception of wire- less messages, and which employs a Card- board Tube wound closely with a layer of fine insulated magnet wire. This method was tried out by a French engineer, P. Dosne, with considerable success in receiv- ing wireless time signals as sent out by the Eiffel Tower Station at Paris, France. In this case the 'phones are shunted across the detector and the detector in turn is joined in series with a fixed or variable condenser and the inductance coil afore- mentioned. In this case no ground what- soever is used. The coil is about 20 inches long; its diameter is 2 inches. At Fig. 6 is depicted a method which was Above: Fig. 3. External View of New tried out by Major G. O. Squier, of Chemical Amplifier. At Left: Fig. the U. S. Signal Corps, some years ago z, Interior of New Amplifier Giving quite successfully for short range work. l.soo Times Original Signal Strength. As observed, two large Iron Nails are driven Into a Tree of fair height; one nail is driven in the trunk of the tree near the electro- magnet. This will be more clearly electrical capacity and inductance, the same ground, while the second nail is driven in understood by referring to a cross -section as any regular antennae, used especially for the trunk just below the foliage. A tun- view of this instrument, which is depicted the purpose. ing coil may be used in series with the in Fig. 1. It consists of a permanent mag- The first scheine, shown in Fig. 1, has 'phone and detector, as the diagram shows, net A, supporting a metallic case N, having recently been tried out by a radio experi- although the coil is not absolutely neces- a threaded screw cap M. The case con- inenter quite successfully, and involves the sary. tains the amplification parts, comprising the use of the metal frame and strings of a Some experimenters have had quite good electro- magnet B, which has a small iron Piano for receiving wireless messages. It success utilizing Wire Fences as antennae. core E connected to a very fine steel dia- may be said that in most of these cases a A gentleman located on Long Island and at phragm D, carrying a cup F upon its Ground connection is invariably used, the a considerable distance from the Sayville surface. Another cup G is placed on the same as with a regular wireless, and the radio station succeeded in picking up the opposite side and within it, the (secret ground wire may be connected to a as, signals from that station very nicely indeed. formula) chemical is placed at I. A tube water or steam pipe in the building. Fail- At Fig. 8 is shown an idea which is often H is provided so that the material is re- ing this, an artificial ground may be pro- adaptable to some experimenters' sur- tained within the cups. The cup G is con- vided by driving a piece of pipe several roundings, and this considers the use of nected to a threaded rod J and lever K. feet into damp earth. Also, the ground the steel Elevator Hoisting Cable as an supported by a rubber standard L on the wire may connect to a metal plate im- antenna. A. peculiar feature about this steel magnet A. The diaphragm D is gold - mersed in a brook, etc. scheme is that as the elevator goes up the plated in order that the chemical will not Of late there has been a great deal heard wave length becomes less and thus, if the affect the steel. The electro- magnet B is regarding the use of Spiral Aerials where elevator is doing service pretty regularly, connected by means of the wires O, while space is at a premium, and Fig. 2 shows there is provided an automatic tuning sys- diaphragm D is joined to wire P. Rod J such a structure. These are said to work tem for the lucky experimenter making use connects to terminal Q. The complete am- over quite long distances indeed. and a of this make -shift aerial. If he should plifier is shown in Fig. J. The knob at great many turns of copper wire are thus happen to use this scheme in such a build- the front is used to regula e the cup G provided, which give the entire aerial con- ing as the 60 -story Woolworth skyscraper siderable inductance value, as will be ap- in New York City he would have indeed preciated. The turns of wire can be quite quite a range of wave lengths automatically Il III tuned in and out several times a minute! A scheme which has been tried out by údiíií>fiIil.Í trodes, consequently varying the resistance 1111111111111111111111111.11111111111 H. Gernsback some years ago with con- 11nnnióómumunir.inl . ,. of the chemical and thus also the phone siderable success in New York City con- ``..tir2 1y;,:;;.} M circuit. A 5 ohm 'phone is used in connec- sisted of pasting or temporarily pinning tion with this apparatus, so it is perceived Tin -foil Strips on the wall of the room, as that a large current Is used in this second- Fig. 9 portrays. Needless to say, all of I31öi rN111]II ti`:>: 4 ??;.t:;., ary circuit. A horn is usually fitted to the the foil strips are overlapped or pinned IIIAAIIIUIIIIII receiver so that messages can be readily together so as to make the whole act as a nannninnuuuunuím 1111111111111'.111111111L'.., heard around the room without using a single capacity area. In these experiments pair of head 'phones. If two or more of he used some 50 square feet of tin -foil. these units are used in tandem signals can Another substitute for the regular an- be boosted to such an audibility that one tennae is a metal ceiling, as pictured in o cannot stay in the room on account of the Fig. 10. ' terrific loudness of the signals. These am- The scheme at Fig. 11 utilizes a Metal plifiers are also used in long distance tele- Bed, such as a brass or iron structure, for phone work and also for detective work an antenna. Fig. i. Diagrammatic View of New Chemical Amplifier. on account of the remarkable sensitiveness. Even Umbrellas with their metal ribs L. Bishop, the inventor of this wonder- will serve for the reception of wireless (Fig. 1) and is used in place of lever K. ful instrument, has spent four long years signals, as Fig. 12 indicates. This is done in order to regulate the pres- experimenting on different types of ampli- In all the diagrams here outlined a sure on the chemical mixture between the fiers and has found after more than a 1,000 -ohm 'phone is preferably used, or cup electrodes. thousand different experiments that the better yet, a pair of them, together with a The action of this amplifier is somewhat chemical amplifier of this type gives the sensitive mineral detector using galena or microphonic, and as the diaphragm is best results. Fig. 2 depicts the interior of silicon, which requires no battery. caused to vibrate by the incoming signals the amplifier, while Fig. 3 illustrates the It goes without saying that where these it varies the distance between the elec- complete apparatus in cabinet. (Continued on page 296.)

www.americanradiohistory.com 1ìl ohcr. I iic THE ELECTRICAL EXPERIMENTER =75 RECEIVING WIRELESS MESSAGES WITH ODD AERIALS

PIANO 2 3 SPIRAI AERIAL rfiRyj(ill1llll!offi10411 -

REC SET

F_ESLAPE

Full Explanatory Text on Opposite Page.

www.americanradiohistory.com 276 THE ELECTRICAL EXPERIMENTER October, 1915 Telemechanics or Control by Radio Waves

THE science of controlling distant ma- mentioned on the design of the boat, as coherer C,, C:, C3 and C. Each coherer chines or devices, such as boats, most readers would probably preier to actuates its own relay R,, R2, etc. The re- airships, or torpedoes, has been make or use a stock form procurable lays in turn control their respective local brought into the public eye very promi- cheaply from most toy stores. circuits through batteries B. B2, mptor A,, nently in the past few years by the suc- Let us now take up the scheme of radio motor B, etc. All batteries can bé of the cess'ul researches of John Hays Ham- wave control applicable to such an experi- flashlight type. mental model. One of the simplest means, Every coherer circuit is properly attuned theoretically (and also practically if the to the various emitted wave lengths by proper apparatus is used), such as a means of tuning coils L,, L2, L3, etc. These quenched spark transmitter. etc., is shown inductances may be shunted by variable in the diagram, Fig. 3. The basis of this whole scheme now under discussion is the accurate transmission and re- ception of sharply tuned waves having different lengths or vibration periods. 1 The arrangement is not com- plicated, although it may ap- pear so at first sight. At the sending station an aerial A, is connected to a variable tuning coil B. It is supposed that several wave lengths or tunes are obtainable in this way, each wave being several hun- dred meters, if necessary, dif- ferent in value from the next nearest wave. For instance, rig. 1. A "Gabet" Radio Controlled Torpedo suppose the six steps shown Fig. z. Miniature Boat With Radio Control Set on Same. in the River Seine, France. vary from each other by a difference of 200 meters. If the switch' condensers to more sharply tune the cir- mond, Jr., and several European scientists. lever B on step 6 gave a wave length of cuits. Also the coils are best made ad- The possibilities and usefulness of "tele- 400 meters, then step S would give 600 justable. A common antenna A serves all mechanics," as this branch of wireless sci meters, etc. As the wave is changed in the the resonant circuits, as well as a common ence is termed, is of great importance in aerial circuit A -B -G the closed oscillating ground G, which can be the metallic hull of time of war. How do we know that some circuit C -Q -D is simultaneously varied in the boat. of the war vessels reported as blown up in proportion so that both open and closed To simplify matters permanent magnet the present war by mines were not blasted oscillating circuits are in syntony or tune. field motors are utilized at As and B, which into eternity by a sharp -nose torpedo If a good quenched spark transmitter is motors, if on a boat, may control, say, the guided by invisible etheric waves? employed the tuning will be very sharp, as rudder and propeller. To cut off the mo- Some six years ago the French tried out we well know. The transmitter may be a tor current from A_ or B two extra tuned a successful wireless circuits with coherers torpedo controlled and relays are neces- from shore by a radio sary, but are not sending station. A shown for the sake of view of one of these Lz l'eceiver clearness. As the vari- demons of war glid- ous waves of differ- through /rore /eng/h ing ing swiftly Con /r0/,Pr - lengths are sent the waters of the out from the trans- River Seine is shown mitter the correspond- in t h e photograph, , ing coherer and relay Fig. 1. This partic- circuits respond ac- ular torpedo carries tuating their respect- antenna structures ive motor circuits. above the water, as Two sits of batter- perceived, and w a s ies are used to control perfected by M. one motor of the type Gabet. Oj mentioned, a n d by A most interesting passing the battery phase of this subject current into the mo- is how can it be done tors in opposite i without t h e etheric directions alternately waves from various 0Gop by the relays R2 and radiotelegraphic sta- R,, for example, t h e tions interfering with, lfo°y motor is caused to, it, causing it to be- r rotate right or l e f t come erratic in i t s iPrope/%r handed, as the case behavior or changing may be. its course? It may fender Jho/t/ mo%r cord rudder This is only one he said that some of Ar idea for radio con- the finer develop- rig. 3 trol and many others ments of the art of have been worked Fig . 3. Control Circuits for Wireless telemechanics a r e. "Telemechanics." out. One of the sim- pretty well locked up in laboratory note spark coil, but preferably a small trans- plest, but disadvantageous in that prompt books as yet, but, however, a few methods former working on 120 or more cycles fre- selective control is not possible can be had of interest to those interested in such work quency A.C. A Clapp -Eastham "hy -tone" by utilizing the old step-by -step relay with are cited here. set will create sharp tuning facilities on 60 a ratchet wheel and pawl. A solenoid or In the diagram, Fig. 2. is outlined the cycles. plunger type electro- magnet acts on a pawl elan for rigging up a small model boat with So much for the emitting of the suc- tooth, as seen in Fig. 4, serving to pull the propelling motors, batteries, wireless con- cessive tunes or waves. At the receiving drum and switch lever S around step by trol devices, aerial, etc. The boat may be station on the model boat or other device step over the various circuit contact but- made of tin or galvanized sheet iron, several attuned circuits are provided. Each tons. 1 -2-3, etc. The contacts are usually soldering all the joints. Details are not properly tuned receiving circuit contains a arranged in a circle.

www.americanradiohistory.com October, 1915 THE ELECTRICAL EXPERIMENTER 277

. A very unique scheme said to be prac- tical is illustrated in the diagram, Fig. 5. Efficiency in the Amateur Radio Station Here the selenium cell is brought into play, By Thomas W. Benson as is well known, changes its elec- which, EFFICIENCY in wireless telegraphy then becomes a three -inch coil condenser, trical resistance in direct proportion to the resolves itself in getting the longest and or amount of light thrown on it. so on indefinitely. strength range and the loudest signal obtain- It is also true that from time to time In this manner a relay is operated with a able with the apparatus in use. Of course selenium cell and battery in series. If the good design is necessary, but the object of close its relay be adjusted so it does not these paragraphs is to point out the best local circuit with the selenium cell in the methods of utilizing instruments that are really unfitted for radio work. For instance, take the amateur who pos- sesses an X -Ray coil. It gives a long thin spark, ideal for the purpose for which it was designed, but in the average set its efficiency is very low. due to the fact that most articles describing the use of coils for radio telegraphy take it for granted that the proper coil is employed, and deal NntiÌiiliiiliÑnnnnr+ with the standard apparatus in connection a:a"..:s::::il:: with it.. A coil of this description when con- nected, as shown in the usual hook -ups, gives a long wave or else a highly ,camped Fig. 4. "Step by S ep" Radio Control Relay. wave. The first is the result of the enor- mous amount of capacity used to shorten cell is exposed to dark; then, when the spark gap. A short gap is neces- light. its resistance falls from 1/4 to 1/6 up the and the sary if the decrement is to be kept low, as or more of its dark resistance. spark gap is a form of resistance which relay deriving more current from the bat- the affects the decrement. On the other hand, Fig z Home-made Compressed Air Spark Gap tery will close. The complete theory of Fig. 5, however, tables appear in the various journals, stat- goes further than this at.d takes into con- ing the number of plates to use with the sideration the latest discoveries in the art, different size coils. I hese tables are very ` I IIIuII IIIIIII I IIp Iryll I IIHII1 cer- in followed out under II when the II fact which made known fact that II Ili VIII good, invaluable selenium will per- { II many amateurs make a seri- tain physical conditions yudlli , QL., n properly, but form its function best as above explained Ili p_ , ous mistake in trying to obtain a very high when a certain colored light, correspond- pitch note with these condensers. They ing to a definite etheric vibration fre- have, in most cases, speeded their inter- quency, is projected against it. With this I:' - rupters up to the limit; when, of course, is in mind, a working arrangement possible _ i_ ' , I these condensers have been adapted for hypothecated at Fig. 5, where a powerful - use with a medium speed interrupter. searchlight A is caused to project various S (v- Therefore, it is necessary to adjust the colored beams of light on to the parabolic voltage and speed of the interrupter for reflector R.F. In the focus of this re- best results or efficiency. of selenium flector are grouped the battery I will not deal with spark gaps here, as a cells 1-2 -3 -4, etc. Each cell operates dis- Fig. 2-A. Compact Arrangement of Wireless they have been well covered in the past, tinct relay, as did the coherers in Fig. 3. Sending Set on Shelf. but one thing necessary is to keep them If a red light is thrown on the selenium cool by radiating wings, air blast or damp- cell, then a "red-sensitive" cell responds, if a small condenser is used to keep with- causing the device carrying it to act ac- in the 200 -meter limit, an extra long gap cordingly. is necessary' and a broad, highly damped This new science is undoubtedly only in wave is emitted. The latter evil is the less its infancy, and at the toddling age at that, noticeable because the Government stations so that the wireless fiend will find plenty will pick up and observe a long wave, pay- ing little or no attention to the badly tuned wave if under 200 meters. Co%f_ sensitirí; Jet Cells Rf The proper method of employing an X- Ray coil for wireless telegraphy is sketched Ajusla* ca/ofsefem in Fig. 1. Here the coil is used without condensers, the aerial itself acting as the capacity, while a lumped inductance, I, is connected in the aerial lead. The gap A- Arc used is of the compressed air type where the spark occurs in air at a pressure of two or three atmospheres. The exact de- sign of the gap is left to the reader, but one that can be easily constructed is shown. Receiver The container is an ordinary Mason fruit Sender jar, one -quart capacity. The standards are a Fig. S. Using the Selenium Cell for Wireless mounted on piece of hard rubber and the Control. pressure is created by a hand bulb acting to keep him busy in this useful branch of through a check valve. Soft rubber gas- the wireless art. kets are used to render the whole air -tight. This method gives a sharp wave of good Fig. 2 -H. Short Wiring Possible for Radio Set MEMBERS OF RADIO CLUB TO carrying power and with a very small gap on Table and Wall. PREPARE FOR COMMERCIAL it may be used with coils under one -inch LICENSES. spark length, whereas the helix cannot be ened sponges, and let me suggest that a A course of lectures and instruction will employed very well. vertical gap be used instead of a horizon- be given to thé members of the Connecti- Another point overlooked in amateur tal in straight gap sets. In rotary and cut Valley Radio Club beginning with its wireless stations is the relation between in- quenched gaps this is not so important. next meeting, and after finishing the course terrupter speed and the high tension con- I have also noticed a number of articles the members are expected to be prepared denser. The usual practise in determining on synchronized rotaries to be used with to take the examinations in Boston for the proper condenser is to build one with spark coils. A much better way is to use first -grade commercial licenses. The future as many plates as the constructor happens the interrupter end of the device and use meetings, which will begin the season in to have. If this condenser stands the dis- a quenched gap instead of the rotary. Less wireless telegraphy, will be featured by charge of a two -inch coil, it is a two -inch noise and more satisfactory results are ob- wireless telegraphy apparatus loaned by coil condenser. If someone else finds that tained. Efficiency again! the various manufacturers. a three -inch coil does not puncture it, it By all means keep the leads as short as

www.americanradiohistory.com _78 THE ELECTRICAL EXPERIMENTER October, 1915

possible. both on the sending and receiving sets. Arrange the instruments in proper An Almost Human Wireless Receiving Set order. If your sending set is on a shelf, An automatic receiving outfit, an "al- the right hand corner of the instrument Fig. 2, "A" offers a suggestion for short most human radio receptor," was the title The condensers are of the variable plate wiring; if on a table and the gap and helix giv_n to his latest device by Mr. Walter type, i. e., instead of varying the dielectric are fastened to the wall, the second sketch, Goodchild, the well -known inventor of the as in the ordinary variable condenser; the "B," will be found of service. Use copper "Permanent Wireless Detector" and other number of plates in use are actually con- scientific apparatus. nected and disconnected electrically by This receiving set is operated entirely by changing the position of the plates. This is an electric motor, as depicted in the center accomplished by the motors and in this of the illustration at Fig. 1. This motor way the condensers are absolute and -relia- operates the various mechanisms by press- ble in their work. Here the proper dials ing any of the control "keys," portrayed depict the capacity of the condensers in the on the front panel, each of which performs regular units. a certain distinct function. The detcctor is of the permanent type and The complete machine comprises a spe- is located inside of the case. as also the bat- cially designed inductive coupler, which teries for driving tit:: motors. The central consists of four reels containing a copper switch is used to vary the current supplied ribbon, one side of which is coated with a to the detector. special flexible insulating compound. These The operation of this remarkable set is reels are wound and unwound as required very simple. requiring merely a pressure on by the motor. Two sets of coils, one pair the right "key, and watching at the same of primaries and one pair of secondaries, are provided. as Fig 2 shows. The induct- Fig. I. Connections for Compressed Air Spark ive value between the primary and second- Gap. ary is changed by moving the secondary back and forth parallel with the primary; strip for the sending set connections, not this is accomplished by the sane motor, "bell wire "1 operated by a different key. A scale and The aerial switch is another energy - needle indicates this inductive value, as wasting device. It puzzles me why ama- seen in the upper part of the instrument at teurs in persist using a switch, which re- Fig. 1. The dial indicator moves accord- quires the best of insulation and is always ing to the position of the secondary coils. more or less bulky, when a small switch The dials on each side of the machine de- properly connected is much better, or even note the ware lengths in meters, corre- a telephone key may be used. In Fig. 3 sponding to the position and amount of a hook -up is shown that has the usual ribbon in use on the coils. aerial switch heat for several reasons. The con- is that does affect Two specially designed variable first leakage not the re- on each side of the appa- sults, thus making it cheaper and easier densers. placed ratus. are illustrated in Fig. 1. These are to construct. Secondly, it enables a sym- motors, metrical wiring diagram to be used. The driven by two separate electric aerial enters at top of window, runs to also operated by control "keys" located on helix, then to switch and thus to ground. An easier, better method is impossible. The compared with home -made variables hook -up, using a telephone key, is also ( which are nothing more than make- added. This may be mounted on a table shifts nine times out of ten). should be and the change -Over can be made in an connected on parallel with the windings. instant with the small finger. Who wants Wave lengths tip to 300 meters may be to use those big switches now? tuned on this coupler; the exact length Turning to the receiving set, most losses depending, of course, on the length of the are incurred in dead ends, poor contacts, aerial. To receive longer waves a second detectors and poor condensers. coupler should be constructed. using 200 To overcome dead ends, use fixed in- to 250 turns on the primary and secondary, ductances and use variables for tuning. respectively. A switch is arranged so as The primary of the coupler should have to throw from one coupler to the other, about 40 turns of No. 24 S.C.C. copper and the fear of "dead ends" is removed. The above construction does away with sliders thus lessening chances and switches, Front and Back Views of Improved Radio of poor contacts. Receiving Set That is Almost Human fieb;rl A The detector is a trouble maker and in Its Working. Fig. t, Above; Tr/ many devices have been produced to ob- Fig. 2, Below. 36 literate this. Galena is the favorite and a time the dial indicators to be see that the stand for this excellent detector should proper wave length is tuned for. It has selected that is sturdy, simple and pro- been found' in testing it out that it takes vided with fine adjustments. V s only 11 seconds to change the wave lengths All condensers should have an air di- from 200 to 8,000 meters. can A The set electric. even the blocking condenser. easily be carried about, as it is very good blocking condenser may be made com- OP.Q.TJIY pactly built, adapting for 4x5 inches. it use on aero- óei:tJ/er./ube from 70 sheets of aluminum, planes, battleships, automobiles, etc., as the s mounted in a case and separated from each WA keyboard can be located in any place de- other by strips of mica at each end. This sired. condenser should be adjustable by a suit- Te%phone able switch. This is another factor for WIRELESS SAVED GERMANY /hey sm/ch obtaining loud signals, which is often over- MANY MILLIONS. looked, as nearly every set of receivers "War has been declared on England. 1. requires a different capacity. The reason Make as quick:y as you can for a neutral for this has puzzled many, but still the port." fact remains. However, it may be more This message, flashed for a radius of clearly understood when the 'phones and 2,000 miles over the system of world - blocking condenser are considered as an girdling German wireless telegraph stations oscillatory circuit tuned to a certain har- at 5 p. m. on Aug. 4. 1914, saved Germany monic of the secondary circuit. As a gen- the bulk of her merchant marine, according eral rule, the higher the resistance the to Godfrey Isaacs managing director of Fig. I. Simplified Transmitting and Receiving ca- Radio Hook -ups. smaller can be the blocking condenser Marconi's Wireless Telegraph Co., London, pacity. England. at a meeting of the company. wire and the secondary 60 turns of No. In closing, I would say, run parallel wires The saving of the Hamburg-American 28 S.C.C. The tubes may be 4 inches and as far apart as possible; cross all wires at liner "Vaterland" alone. he added, more 3% inches in diameter, respectively. The right angles and solder each and every than balanced the $10,000,000 Germany had variables, of a good commercial make, as joint. expended in erecting the stations.

www.americanradiohistory.com October, 1915 THE ELECTRICAL EXPERIMENTER 279 GUIDE FOR AERIAL ROPES. AN EFFICIENT AERIAL CON- NEW BUZZER TEST RESONATOR A simple but efficient rope guide for an NECTOR. COIL. aerial pulley may be made from a t/4 -inch Many wireless troubles result from A new and effective buzzer test circuit bolt about 6 inches long and a couple of loose, weak or faulty connections, and the intensifier, in the form of a specially nuts. The bolt is bent, after the head has device described and depicted herewith wound inductance, has recently been per- been cut off, in a circle to fit the rope. A practically eliminates all troubles arising fected and placed on the market. The illus- hole is then bored into the aerial mast to therefrom. tration depicts the appearance of the It consists of a simple block of hard resonator coil, and it is c.aimed that adjust- wood, shaped somewhat like a triangle, as ing radio detec- shown in sketch 1. It should be boiled in tors becomes a wax. Four holes are bored at the top of pleasure with this the block to admit four binding posts from resonator, when "dead" dry cells. Another hole is drilled connected in at the bottom, where the two sides of the series with t h e block meet, for the same purpose. Insert buzzer test cir- loosely all the posts and then take some cuit wire. No. 19 aerial wire and lead around all the Presumably the posts, arranging as per dotted lines, from device acts to in- one to the other. Small grooves may he crease induction made on the back of the block and wire in the circuit, and squeezed snugly into these. Tighten the as the buzzer test nuts on the posts and fasten the rat -tails currents are a and lead -in to posts. series of rapidly oscillating or interrupted The illustration clearly shows the device currents it is evident how this inductance Guide or Aerial Ropes to Prevent Jumping Off attached, but it may be stated that all such in the circuit can "boost" these currents so Pulley. "connectors" usually extend down from as to give a magnified effect when they fit the bolt, and a nut is put on each side about 15 to 25 feet from aerial. Lead -in reach the detector and phones. of the mast. The guide should be placed It is said to be particularly efficacious about 3 or 4 inches below the pulley. This when utilized in conjunction with the well - simple device often saves much trouble known .Crystaloi detector. It is finished in when the rope catches in the pulley. Con- hard rubber composition and is a neat addi- tributed by W. R. MILNER. tion to any radio receiving set. LOOSENING CORRODED BATTERY NEW TURNBUCKLE INSULATOR. TERMINALS. has It is sometimes very liard to loosen the A useful form of strain insulator terminal nuts on storage batteries. This is been patented, and description follows: often true when no great care has been, The device as completed forms a turn- taken to see that the terminals were free buckle having, a body or shank of insulat- from the acid used in the battery before ing material 10, and having threaded eye the terminal nut was screwed on. In cases bolts engaging threaded bolt- receiving where these nuts "stick" it shou:d be re- members 12 imbedded in the ends thereof, membered that if too much force is uses; and these bolt- receiving members are in the terminal is likely to be torn off bodily. turn firmly anchored in the insulating body The best method that I have found to so that the device will possess great me- remove them is to use a pair of pliers c:ianical strength. Its insulating value is which have been made fairly hot and to also very high, since the terminals are sep- hold the terminal nut with them until the arated by the body of the insulating ma- terminal parts are heated through. The terial in which they are imbedded. nut will then turn quite easily. It is well The device can be adjusted to tighten to cover the screw threads of the terminal or loosen the wire or cable in which it is with vaseline, after cleaning them thor- inserted by rotating the body or shank 10. oughly from acid, before the nut is ap- This can be done by inserting a tool such plied. If this is done there should be little a or screwdriver into the central trouble from as rod corroding. hole 16 so that a great leverage may be Contributed by obtained. This central hole is lined with MILTON E. SAUL. a metallic sleeve so that abrasion of the [Soaking the terminals in strong am- brittle insulating material wad be pre- monia for 30 minutes accomplishes the trans- same purpose. vented. since the tool engages and -Editor.] mits the force through the sleeve 16, which The AN INSULATED TURNBUCKLE. Antenna Connector Made of Wood. is imbedded in the insulating body. Here is an easy way of combining the in- sleeve 16 is positioned between the ends of sulator can be made of from No. 10 to No. 4 wire. the sleeves 12, and is therefore insulated and turnbuckle on the guys of a Contributed by WILLIE WOTON. wireless pole into one piece, thus strength- from both of these sleeves and from the ening the guys by not breaking them up eye bolts and the wire in which the device into several parts to insert insulators and SOME PRACTICAL HINTS. turnbuckles. A short permanent horseshoe magnet fastened to the end of a stick is a most handy article for locating and recovering small screws dropped to the floor from the work-bench. You do not have to get off your seat and get down on all fours to hunt for them. Slide the magnet slow!) over parts of the floor and soon the screw will be found attached. (Provided it ain't a brass anc!-Ed.) \O\ , :...J .... _ Plain newspaper rolled into a small tube ss 16 makes a cheap and handy brush for ap- 77l t\ plying lacquefs, etc., and also saves the Newly Patented Adjustable Turnbuckle. Insulated Turnbuckle. trouble encountered when you failed to The insulated turnbuckle herewith de- clean the brush last time and wish to use is inserted; the device may therefore be scribed consists of three parts, namely, the it again. adjusted to tighten or loosen the wire with- turnbuckle, which in this case is an ordi- Often it is desired to know if an arc out danger of shock even if one of the eye nary 7 -inch carriage bolt having a diameter lamp is being fed by A. C. or D. C. A bolts is connected to a high- tension wire. of Y4 of an inch, and two standard porce- sure and quick test can be made by taking lain insulators. They should be arranged a hexagonal pencil and holding it at one as shown in diagram. To tighten the guys end, and slowly pass it horizontally from if D. 'C., it appears to be at rest in the it is only necessary to tighten the end nut of side to side before your eyes. If A. C., the hand. Contributed by the bolt. pencil seems to rapidly revolve in the hand; GUY H. DALTON.

www.americanradiohistory.com 280 THE ELECTRICAL EXPERIMENTER October, 1915

THE "BRODIE" DETECTOR. lieve the description sufficiently clear to al- LONG ISLAND BOYS STUDY The subject of detectors has been well low of the amateur building this instru- WIRELESS. .covered in the past by this magazine, but ment, which will always be ready in a The establishment of the wireless plant I believe the one herewith described de- pinch. Contributed by in Sayville has given an impetus to the serves a place on the list. I have nick- THOMAS W. BENSON. study of the tvire:ess among Sayville, L. I., named it the "Brodie" detector, as the ele- school boys, a large number of whom have ment of chance is foremost in adjusting it. WINDOW SCREEN SERVES AS receiving apparatus. A number of them The principal part consists of a micro- ANTENNA. are also members of the Sayville troop, phone mouthpiece with 10 saw -slots one - While my regular antenna was down Boy Scouts. They have organized a wire- eighth of an inch deep, spaced equidistant- less class under the direction of First Class ly around its edge. A small wooden box, Electrician Dunkie, who is a Government 5x3x1 inches, forms a very good base for operator at the station. it. In addition you will need the follow- ing: 10 switch points, 1 switch lever; 2 ANENT DR. COHEN'S NEW NAVY binding posts; 1 threaded brass rod 2% TYPE RADIO SET. inches long. and 2 nuts for same; one In the July issue of the Electrical Ex- 1/2-inch inside diameter brass tube, 1 inch perimenter I took particular note of Dr. long; 1 fiber washer, % -inch diameter; 1 Cohen's improved Navy set and hooked up lid of wooden pill box about 1tf inches my set in the identical manner, and must diameter; 10 pieces soft brass wire about say that the selectivity is wonderful. No. 24. However, for the benefit of amateurs The mouthpiece (after the slots are cut) contemplating using Dr. Cohen's hook -up, should have the perforations in the center I wish to contribute a diagram which was knocked out, but the outer row of holes tried out on my set and tested by me. It should be left intact. is similar to the improved style, except Take the brass wire, tie a knot on one that every turn of inductance on the pri- end, put each wire in a slot with the knotted Window Screen Radio Antenna. mary and secondary may be obtained. end outside and run the wire down the inside of the mouthpiece and through one temporarily I experimented with various of the holes of the perforated shield at substitutes. back. Upon connecting my receiving set to an After putting all the wires in place, lay ordinary window screen I found that sig- it aside. Now take the box and cut a hole nals from a local spark -coil station about one inch from one end to allow the thread one -quarter mile away were received al- most as loud as on my regular aerial. small transmitting set consisting of an " Electro" 1/2-inch Bulldog spark -coil, gap and key was then hooked up with this novel antenna and, wish the addition of an aerial switch, regular communication was carried on. Slightly better results were obtained by connecting two screens t l- gether. Neither station was grounded on water pipes, but to metal plates buried in the ground at each station, so that there was no metallic connection between the two stations. The screen used was of or- dinary size and not more than 12 or 15 feet above ground. When using a sending set with an aerial of this kind it is absolutely necessary that Multiple Contact "Brodie" Detector. all connections between coil, gap and screen be as short as possible and fairly heavy in on the mouthpiece to fit in without slipping crder to secure good results. through. At the other end lily out and Contributed by drill holes for a ten -point switch. as shown DONALD PALMETER. in illustration. Drill holes for binding posts at back. After staining woodwork to suit taste of builder, we can assemble GOLF -BALL AERIAL INSULATORS. A very good aerial insulator may be Modified Hook -up and Construction for Dr. the various parts. Cohen's New Wireless Receiving Set. The drawing will be of great assistance made from a golf ball, the solid gut'a in assembling, therefore it should be close- percha kind being the best. The amateur will find this to his advan- ly studied. Plaee the transmitter mouth- First, it may be well to remove the paint, tuning it has no equal. like due to the tage and for sharp piece in place in the hole and carefully because it acts a conductor, Contributed by separate wires inside of the box. Take lead in the pain-; it may be done by ap- HARRY Y. HIGGS, R.E. the pill box, which has a hole drilled plying a coat of paint remover. This ac- through the ce:iter large enough to pass complished, take a small drill and at op- ends drill holes a short way in. NEW CARNEGIE INSTITUTE OF the threaded. rod. Put rod through it with posite TECHNOLOGY RADIO PLANT. nut Now take a few brass screw -eyes and on end, pass up through center of the Institute mouthpiece, drop fiber washer over rod, At a cost of $1,500 Carnegie II of Technology, at Pittsburgh, Pa., is in- then the brass tube, a washer and finally Machinery Hall a the other nut. Center the tube and stating in the tower of screw III IIIIIIIII be the most up tight after wires e new rad :o plant which will drawing the brass taut. powerful in that part of the country. The Connect each wire to a contact on the 111,- outfit will have a wide range over which it switch, threading a band of paper or thin may communicate, the western boundary fiber between them, so they don't touch. being Honolulu and the eastern Germany. After connectink one binding post to the Communication will also be established -center brass tube and the other to the with other technical schools throughout the switch lever, the detector is ready for use. wh:ch have radio equipment. use, the galena into country To break up pieces Golf Balls Prove Good for Insulators The other station is being installed for about as large as a pea and drop into the use of the student Radio Club, an or- mouthpiece around center tube. The switch t'iread them in the holes made, being care- ganization of electrical students. The -is quickly moved from point to point until ful that they do not touch at the center. equipment of the new set consists of a an adjustment is found. By following the drawing, all points will 10 -kw. motor -generator of the latest de- Although there is no law of physics that be made clear. These insulators will be sign and an Audion detector. states that a sensitive spot will be found, found to be very strong and also will re- it is surprising to get at least two points sist fairly high voltages. Several may be If you are a "newsstands reader," look to respond on the first trial, if the mineral joined in series to increase the insulation sharp next month. We are changing the is at all good. value. Contributed by heading of our cover to make it more With the assistance of the drawing I be- F. PELTON. readable. You will like it, too.

www.americanradiohistory.com October, 1915 THE ELECTRICAL EXPERIMENTER 281 l

A GEISSLER TUBE EFFECT. SPIRAL INDOOR AERIALS. ably greater than the capacity. The device Connect a small Geissler tube to a gas 1V here aerials are desired for wireless which will now be described consists of two engine or other small spark coil and shunt experimental purposes, etc., in apartments coils having coupling between them; one a spark gap around it, as indicated in sketch. and other places where it is not desirable coil being connected in series with the pri- Now adjust the gap so that when mary and the other in series with the the coil is started the discharge will secondary of the loose coupler. just fail to pass through the tube. Obtain three circles of 1/4-inch wood I1 If the setting has been carefully 5 inches in diameter and two discs made the coil may now be operated 4 inches in diameter. Glue these to- without pru.ducing a glow in the tube gether so that they will appear as as long as the tuba is kept in the in Fig. 1. Wind one o,f the grooves dark. If a light from the spark gap full of No. 20 S. S. C. wire and the or any ordinary light be allowed to other full of No. 30 S. S. C. wire. fall on the tube a discharge will The wire should be wound on rough- begin at once and will continue as ly, crossing the turns as much as long as the coil is operated. The possible. Enamel wire should not be current may be cut off at any time used. The coils may then be mounted and the performance repeated indefi- nn a base as shown in Fig. 2, the nitely. ends of each coil being brought out A rather interesting way of show- to binding posts. Connect up as. ing the effect is to "light" the tube shown in Fig. 3.- Contributed by with a match. For the success of the IRVING BYRNES. experiment the adjustment must be such that a very slight change in con- GAS JACKET FOR ditions will cause a discharge. The DETECTORS. gap must be set apart as widely as Herewith you will find notes and on a new form possible and the vibrator of the coil Spiral Antenna for Small drawing constructing should operate very steadily. Spaces. of detector. All the material can be My explanation of the effect obtained is to place long stretches of wire on the roof, obtained around the experimenter's work- that the light thrown upon the tube ionizes the newly devised spiral aerial will be shop. the gas, making it more conducting and found very suitable for the purpose. This In the drawing A is a circular base hav- thus lowering the potential needed to pro- form of aerial, of course, possesses a large ing a groove B about Y4 inch deep and duce a glow discharge to a value below amount of inductance in proportion to its the diameter of a good sized jelly glass. that of the applied potential. actual length when opened up. It can be C is a detector of the cat whisker type, With most Geissler tubes the effect is used in an ordinary room, and as it may very difficult to obtain if the regular sealed - be made with a large number of turns in in electrodes are used. Temporary con- same, spaced even as close as % to % inch, denser electrodes are made by wrapping it can be seen that the inductance will reach a large value. Hence its receiving activi- ties and also wave length capacity will be quite appreciable. It has been stated that with this form of aerial it has been possible to pick up radio messages over distances of 1,500 miles and more. Strings may be used fastened to each turn in the helical aerial, so as to help support same in a straight line, or nearly so, between the end spreaders. These spreaders may be made of two crossbars of wood. Two heavy wireless insulators placed in either suspension rope supporting the aerial will insulate it nicely. It can be composed of 50 to 100 turns or more of No. 14 solid conductor or stranded cable with a turn diameter of 1 to P.4 Light of Match Starts Spark Through Tut,e feet. tinfoil bands around the tube near each A DUPLEX LOADING COIL. end and the coil leads are connected to these. Contributed by S. KRUSE. The following is a description of an in- strument which should be found in every OVER 4,000 MARCONI RADIO MEN radio station. It is known as a duplex load- IN EUROPEAN WAR. ing coil, as it allows both the primary and Detector in Gas Chamber. Presiding at the annual meeting of the secondary circuits of a loose coupler to be Marconi International Marine Communica- adjusted to long wave lengths. If induct- w't:i connections to two bindings as usual. tion Company, Godfrey Isaacs expressed ance is added to the secondary circuit and At D a short length of glass tubing is put the regret of William Marconi at his in- that inductance inductively coupled to the through the base. Great care must be ability to be present. primary circuit very good results will be taken so that it will fit tight. Mr. Marconi, said Mr. Isaacs, had been The detector stand should be firmly called upon by his Government and had' fastened down and the glass tubing al- joined the engineering staff of the Italian lowed to go through the table to which the Army in order to superintend the organiza- detector is fastened. tion of its wireless communications. At no Then adjust the detector; put the glass it time had the value of Mr. Marconï s inven- over and connect a piece of rubber tion been more prominently emphasized tubing to D. This tubing is connected than since the outbreak of the war, and to a bottle of hydrogen gas which may be when peace was obtained an interesting caught by a downward displacement of wa- chapter might be written of the part played ter, etc. A pinchcock should be fastened at by the 2,000 Marconi stations fitted upon F. One will be surprised at the increase in vesses of the mercantile marine. the strength of the signals. Over 4,000 Marconi operators, said Mr. Contributed by RAD COOVER. - Isaacs, were in the service of the British [This suggests a good field for research Army and Navy, and the Admiralty had, on by the radio experimenter. Tests of differ- more than one occasion, expressed appre- ent temperatures would also be worth ciation of the resource and courage dis- Making a Duplex Loading Coil. zchile. -En. ] played by the men. obtained. Of course, increased capacity The correct time by wireless from Ar- Now is the best time of the year to erect could be added to the closed circuit, but it lington, Va., will check the clocks and an aerial or to overhaul an old one. Better has been found that for the loudest signals watches at Tobin & Canham's jewelry store get busy. the inductance employed should be consider- in Springfield, Ill.

www.americanradiohistory.com zS. THE ELECTRICAL EXPERIMENTER October, 1915

This department will award the following monthly prizes: FIRST PRIZE, $8.00; SECOND PRIZE, $2.00; "fillED PRIZE, $1.00. The idea of this department is to accomplish 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 ideas submitted a prize of $8.00 will be given; for the second best idea a $2.00 prize, and for the third best a prize of $1.00. The article need not be very elaborate, and rough sketches are sufficient. We will make the me- chanical drawings.

FIRST PRIZE $3.00. SECOND PRIZE $2.00. THIRD PRIZE $1.00. SIMPLE ARC LAMP. AN ELECTRIC "GOAT" FOR AN ELECTRIC MOUSE TRAP A simple hand -feed for arc lamps is LODGES. ALARM. given below. At C C are the carbons. P P' I give herewith a sketch of an electrically The diagram herewith given depicts a are standards. I have large ones so as to charged chair, and below, a brief outline novel little mouse trap alarm attachment hold large carbons. S S are brass sup- of method of setting up same. Near the "trap" door is driven a nai ports, which I use to hold base above Tlls chair will afford unlimited amuse- so that when the door of the trap shuts it ment in your office and probably rid it of a few chair warmers, and for lodge "initia- tions" it is the boss stunt. Drive four small wire brads (a) into the under side of chair seat, letting just the points appear on the upper side of seat. With a fine nail set drive them back so that they remain just below the surface. Fasten a small induction coil (c), and a battery (b) under the seat, soldering the secondary wires (f) to the ends of the brads (a). The parts of the switch (d) can be made from small strips of brass or Efficient Hand -feed Arc Lamp. table J. S' is a spring used to hold back Mouse Trap Alarm. cup D, P', which is soldered in detector will touch the nail firmly. Two wires are in a brass slide about 31/2 which slides fastened, one on the nail and the other to B 4 inches of threaded inches long. is the trap, and connected up, as shown in brass rod which screws through support diagram. When has threaded hole in it. K is Mr. Mouse enters and W, which a attacks the cheese, the door closes, knob. The base is 11 by 3 which a typewriter causes the current to flow and rings the inches and is of wood or slate. The wire bell. current can be fastened in to carry the Of course this alarm is not always neces- as the carbons are, or can be same place sary, but those wishing a mouse trap alarm by separate binding posts placed on held for traps located at a distance will find the base. I hope that this contributor this most the readers of The useful. will be of some use to Contributed by BERNARD COHEN. Electrical Experimenter. Contributed by 1r- EDWARD RHOADES. water. This will neutralize any acid which may be left. FOR FISH. The following suggestion may be useful AN ELECTRIC LURE to those making use of steel files: Every good fisherman knows that a light Thoroughly clean the be file from any will attract fish. A simple light can grease, oil, alkali, soda or potash and dip jar, cutting a made by taking a pint fruit it into a solution of 1 part nitric acid, 3 3/4-in. hole in the top of the cover, insert- parts sulphuric acid, 7 parrs water, by ing a piece of gas pipe in the hole and weight, for from five seconds to five min- soldering it to the cover. Insulated wires An Electric "(boat" Chair for Lodges. utes. Then wash in hot water; dip in lime are run through the pipe, and a small elec- water and oil to prevent rusting. tric globe is attached to the ends in the copper, and screwed to the back of char, Contributed by G. J. ENGLESTEAD. as shown. The switch can be covered up by fake upholstery, etc. A POCKET -SIZE BATTERY RHEO- Run the wires (e) down the back of STAT. c:tair to coil and battery, keeping them out A pocket regulator for battery currents of sight as much as possible. The switch is made from a piece of small glass tubing, (d) is concealed by a pad or drape of some

kind thrown over the back of the chair, 111 II as aforementioned and the chair is ready

for the first victim. When said victim 1111 J111111E11 leans back against the switch (d), closing gil the battery circuit with the coil (c), the fireworks begin. The coil may be a / to R 1 -inch spark coil, and it is well to cover lile 1111ilf il 11 over the bottom and legs of the chair with cloth, etc. Contributed by Simple Pocket Size Rheostat. C. F. CONANT. carbon grains, a match, tinfoil and a knob. The match is fastened into the knob and FLUID Luring Fish by Electric Lamp In Bottle. RECIPES FOR ERASING covered with tin foil, so that it will slide AND CLEANING FILES. loosely in the tube. Stop the other end jar. The other ends of the wires are at- For obliterating ordinary script, prepare with tinfoil and fill in the '/á -inch space with tached to a pocket battery. The jar is a solution of chlorine gas in water. Take carbon grains. To regulate this move the placed under water and the light turned a freshly written copy and wash repeatedly match in and out. on, which attracts the fish. with this solution and then with some lime Contributed by J. H. WILSON.

www.americanradiohistory.com October, 1915 THE ELECTRICAL EXPERIMENTER 283

AN INTERESTING EXPERIMENT be used a magnet may also be adjusted to A HOME -MADE WIRE TESTER. WITH "WIRED GLASS." the rear wheel, so as to protect the rear Many times there is a hurried demand What might be termed "an interesting tires from such mishaps as aforementioned, for a reliable and sure wire tester to test and peculiar spark effect" can be carried and this will be found very serviceable some wire efficiently. The following is al- out by procuring a piece of window glass, should it become necessary to back the most one of the simplest conceivable. with chicken wire made into it, commonly vehicle up. Articles necessary are: A common clothes used in factory windows and doors. Now Sketch is herewith shown as to how pin, a sharp- pointed nail or carpet tack, a shellac one side of the glass and place a the magnet is applied. This device is very binding post, some very small tacks and a sheet of tinfoil on it having a smaller area practical, and at the end of a long ride or sheet of brass or metal. than the glass. Before placing the tinfoil trip, if the rider or driver will examine his First cut out a thin brass strip the exact magnets, he will realize how many times length of one of the jaws of the clothes his tires were endangered, but thanks to pin and fasten it on by some very small my invention, saved! Contributed by HARRY S. PAINE. 0 IIIIÌ "SOME" CHICKEN THIEF ALARM. I herewith give a suggestion which I am sure will remedy and comply with all de- mands of the suburban districts where the theft of poultry from the chicken houses is exercised without detection. Procure a medical or spark coil, a few Test C p Made From Clothes Pin dry cells, a tack, some bare copper wire, insulated wire, a switch and a few staples. tacks. (The heavy line in the drawing 'Wired Glass" Gives Spectacular Spark Effects. We will first consider the pole on which denotes the strip of brass.) Fasten it on one of the your pin and also paint it black, and this face shall be the chickens rest at night. Cut two single either jaws of on, attach a binding post as shown. Now toward the glass. Break off all the wires pieces from the bare copper wire a few except one, inches longer than the role, and by means drite a sharp- pointed nail or tack about 1t/s around the edge of the glass inches above the binding post and your and this is used for one connection as of small staples tack the wires about Y_ inch entire length of tester is complete. It works as follows: shown. Now, by connecting a 1 -inch or, apart along the the in 1. 2 gives Presume that you wish to test some in- still better, a 2 -inch coil to this glass ar- pole as shown Fig. (Fig. a the of top view of the pole showing how wires, sulated wire. You push the tester into the rangement and darkening spark gap wire is firmly gripped or and tak- etc., are arranged.) Then place the coil in so that it by the the coil in a paper wooden box, of the tester. It is the same if a most won- a corner and, after removing both elec- jaws just as ing the whole in a dark room, the wire to be tested was a clothes line and derful phenomenon will be noticed. When trodes from the binding posts on the side of coil, connect one insulated wire and you were hanging up wash by the use of the current is turned on the glass will all clothes pins. The sharp- pointed nail or tack light up with a violet hue in the form of pierces the insulation on the wire until it the wire and li.tle bubbles in the glass will has the bare copper wire thoroughly in its become fluorescent, each in a different grip. There's where the excellent connec- color, probably due to gas formed when the tion comes in, and although the clothes pin, the wire was plunged into molten glass. in fact, the whole device, looks so odd and Contributed by simple, yet it cannot be overestimated in its JOHN SEDGWICE. various uses. Contributed by HENRY BROWN. SO YOU WON'T HAVE TO "GET OUT AND GET UNDER." COLORED LAMPS IN WINDOW Have you ever leaned back among the DISPLAY. cushioned comfortableness of your motor One of the most attractive window dis- car on a scorching hot day, when your car plays can be mad by using colored lamps went spinning along wafting delightful and connected to flashers, giving an illumina- fragrantly cool breezes to you, and blessed tion variabl, in color. The advantage of the wonderful invention of this means of Electric Chicken -Thief Alarm. this effect is that it has an almost universal refreshment? when bang! would come a application. Any kind of goods can be loud report and the blissful trend of lead it to one of the bare wire ends, as shown to advantage. thoughts would be broken, your ease dis- shown protruding from the chicken pole. turbed to the extent that you would vexa- By means of tape, insulate the connections tiously have to "get out and get under" to well. The other connections may be made fix that "tiresome" tire. But at last has by following the diagram, which is self - been found a remedy which will obliterate explanatory. the thoughts which usually give vent to The switching mechanism of the device profane expression, significant of a punc- is now constructed. Although very simple, tured tire. it controls the entire operation of the in- strument. Drive a tack in at the top of your door. Procure a string about 6 feet long and in .he center of it fasten a rubber band as shown. Fasten the string to the tack on the door, drive a small staple about 2 inches above and pass cord over a pulley to the switch handle as illustrated. Connect one point of the switch to one of the wires from the battery, and the handle of switch to one post on coil. The instrument is now completed and ready for operation. As soon as the intruder opens the door the string pulls the switch handle over to the switch point, both of which are in cir- cuit, and naturally the coil is actuated. This Magnets on Autos Pick up Tacks and Nails. sends a high- tension current through the This aid has come in the form of a bare wires on the pole and the chickens powerful electro- magnet, which may be at- clutching it receive a "shock" and leap or Ever -Changing Colored Lamps Give lieautitul tached in the front of the wheel or wheels fly about, cackling, and otherwise venting Window Display. of any tired vehicle, as illustrated herewith. their disapproval. This will arouse the Any steel or iron particles, such as nails, owner, and the unwelcome visitor will be A box with an opening in front as indi- tacks, etc., lying along the road will be welcomed in a manner that he (the owner) cated is painted a dead black inside and the picked up by this magnet, and thus prevent sees fit. Contributed by back is lin with back velvet. Red. green a puncture. If a truck or automobile is to WILLIAM WARNECKE, JR. and blue lamps are used as shown, the wir-

www.americanradiohistory.com 284 THE ELECTRICAL EXPERIMENTER October, 1915' ing being very simple. The lamps being tric bell, minus the gong. A switch is fas- water and gas pipes in his house and in shielded from the observer the and inside tened on side or top of box. A 3 -volt some cases he detected 1 /60 of a volt. He of the box being black, the goods exhibited "Radio" dry cell is preferable, as this elimi- also very ingeniously appear to undergo arranged a method mysterious changes in nates the bulk of other batteries, giving of telegraphic signaling with a friend re- color. only 1% volts. A diagram of the wiring siding about 4 mile away from his house. The number of lamps to be used depends is given herewith. The bell should be This signaling was upon the carried out by having size of the box, and likewise upon 'his galvanometer connected across the gas the surroundings. Twice as many blue and water pipes and his friend simply ar- lamps should be used, for their intensity is ranged a Morse lower key or push button across than the green or red lamps. If the the gas and water pipes in his laboratory lamps are 60 watt Mazda, the number of % mile away. lamps shown in the illustration will b: suf- This experiment is very interesting and ficient to display in a box with an opening it hardly seems possible that such an ar- 20 inches square. The more lamps used, rangement would work however, the more striking over distances of is the effect. i mile, but it is a matter of fact that it This sort of window display should be o: has worked, and further service experimenting to the florist who is intending to ad- along this line would seem indeed worth vertise his flowers. The flashers can be of while. the thermostat tyre, which operate auto- matically and are very cheap to purchase. The best method of switching on the va- A CHAIN PULL FOR KEY rious colored lamps successively, however, SOCKETS. would be by means of a small motor -driven Here is a valuable idea which your read- flasher with rotating metal segments and ers can use successfully on any socket key brushes in the place of the thermostatic of their electric lighting system. Only a flashers mentioned. With a little ingenuity piece of stiff metal and a gilt chain or cord on the reader's part such a commutator is necessary. Mark out (see Fig. 1) and flasher arrangement can be easily impro- then cut around the dotted lines made. Window Tapper Made From Ordinary Bell and vised. Contributed by Battery. Fold over and put on finishing touches as il- A. FLORIA. mounted about 1 inch over the cover from A WIRE INSULATION REMOVER. the edge, and the best effects are obtained To scrape the insulation by placing the box in a corner of the store off wire with a hammer of the knife blade or pliers is a very slow and window and bending the tiresome job, as every experimenter knows. bell to give the proper adjustment to the In order to make this work easier, the fol- window pane. The bell will work intermittently or con- stantly, as desired, and the hammer vi- brating against the glass of the store win- dow produces an ear -shattering noise, which naturally attracts the inquisitive passer -by. Contributed by _á W. R. WELLS. e.. DETECTING ELECTRIC CURRENT BETWEEN WATER AND GAS PIPES. Those having a sensitive galvanometer at hand will find it interesting to conduct experiments to see if they can detect any electrical potential differences between the gas and water pipes in their house or laboratories. In some cases this amounts to a considerable voltage. The sketch herewith shows how a re- Effective Insulation Scraper. flecting galvanometer is arranged with a lowing directions may be employed: scale and a lamp which throws a beam of Procure a piece of spring steel about 9 light through the small hole in the scale inches long and 1 inch wide (a heavy clock proper. This beam of light strikes the or phonograph spring will serve the pur- small mirror in the reflecting galvanom- pose). and with a file make a V- shaped eter and reads across the scale by re- notch in each end, as shown in the draw- Chain bull ing. One side of the notch should be made Attachment for Key Sockets. a little shorter than the other, sl that the in Fig. 2. Then Con/ro/ /log lustrated slip the novelty wire can the more easily be inserted. Now into your key of socket and it will work bend over carefully the ends at the dot- magner lines as Rdiededmys simply, easily and reliably. It has the "chain ted illustrated, because spring pull" effect, and you will find if you make steel when cold is very apt to break. It is Oirearogs (rom one that you will make more and more un- a good idea to heat the spring where it is bent. lamp til there is one on every socket key. to be over a bunsen burner, so, as to Contributed by insure its flexibility. The notches should FRED WARNER. then be sharply ground and the scraper shaped as sketch shows. The scraper is INLAND WEATHER FORECASTS used by inserting the wire in the notch, BY WIRELESS. pressing the sides together with the hand The distribution of marine weather fore - and drawing the wire through. /kre¡sinq / SM. casts and warnings by radio -telegraphy is Contributed by well known, but the use of this method of FRANK J. L. HAVERLAND, JR. Jhort divi: conveying weather information to inland iJ//ry Jwilch dwellers is about to be tried for the first AN ELECTRIC WINDOW TAPPER time in this country. Arrangements have This little device can also be termed a Detecting Stray Earth Currents. been made to send out a wireless forecast "show window attractor," and is commonly daily, between 12.45 and 1 p. m., from used in electrical and other stores. To flection, according to the magnitude of the Illiopolis, Ill., to all receiving stations construct, the following directions will be current passing through the galvanometer within a radius of 12.5 miles. The messages serviceable: windings or coils. will be sent slowly (10 to 12 words a min- A box 8 inches long by 3% by 4 inches, An English experimenter recently stated ute) for the accommodation of amateur with a hinged cover, is necessary. Mount that he had measured considerable electri- operators who are not sufficiently expert to on the cover with screws, a common elec- cal current potentials existing between receive faster.

www.americanradiohistory.com October, 1915 THE ELECTRICAL EXPERIMENTER 285

in an earthenware pot for three to five INTERESTING EXPERIMENTS minutes. Remove, dry and polish. FOR THE AMATEUR CHEMIST. Bluing of Steel. -Heat the steel over a The following experiments can be per- flame of alcohol and varnish with a mix- formed with household chemicals: Prussian ture of Blue and Alcoholic you possess a battery giving from 4 to Use thin If Shellac Varnish. a varnish. Of 20 volts you can perform the following course this is only an imitation of bluing, experiment, which is particularly interest- and the article has to be lacquered to make ing on account of the variation of results, it wear. with apparently the same conditions: Real Bluing of Stecl. -This formula is used to blue revolver parts, vibrators, steel Immerse two pieces of brass in a strong knives, etc. ì\1.x carefully together 25 solution of common salt or sal -ammoniac parts of Trichloride of Antimony, 25 parts and water. Connect one piece to the posi- of Fuming Nitric Acid, 50 parts of Hydro- tive wire and the other to the negative, chloric Acid. Tie a rag to a stick and taking care that the brass pieces do not apply the mixture freely. After rubbing touch each other. EDITED BY S.GERNSBACK the article with a flannel it may be polished After the current has passed for one or Under this heading we will publish every month on a polishing head with a green oak wheel two minutes the solution will become col- useful information in Mechanics, Electricity and um,' an even, clear blue is obtained. ored, and if the process is continued a Chemistry. We shall be pleased, of course, to have Revolver colored pigment will be precipitated. The our readers send us any recipes, formulas, wrinkles, Barrel Bluing. -Clean the bar- new ideas etc.. useful to the experimenter, which rel with emery cloth ; remove all grease color of the precipitant varies considerably will be duly paid for, upon publication, if acceptable. with lime and polish the surfaces. Take and may be either red, purple, green, blue, fine and clean wood ashes in a muffle, put orange and possibly others, depending on the barrel in the middle and heat the the strength of the current and the compo- EXPERIMENTERS APHORISMS. sition of the brass. In the following, we wish to give to the muffle to a temperature of cherry red. Experimenter some hints as to the use of the \V.th a pair of tongs, remove the article The Grand Rapids can be made as fol- different Ingredients and fuw to work them: from time to time to see if a dark blue lows : Fill a tumbler or test tube with (t) Always bear in mind that exact working of a formula requires ACCURACY, CLEANLI- can be obtained when cooled in the air. water, throw upon its surface a few frag- NESS, PATIENCE, and SKILL. When the desired color is obtained take ments or thin shavings of camphor gum (z) Know what you ore about, before you start the barrel out and let it cool in THE AIR. and they will instantly to move and to experiment. begin (3) "THE HISTORY OF FAILURES IS THE Finish with Boiled Oil and polish. acquire a motion both progressive and ro- HISTORY OF SUCCESS" goes an old adage, and Bluing Steel.-A very simple process is tary, which will continue for a considerable it applies well to the experimenter. Melt period of time. the water be (4) Many times impure, wrong or deteriorated the following: Saltpeter in an iron If touched raw materials, spell FAILURE Instead of SUC- pot. Clean and polish the steel article and by any greasy substance the floating par- CESS. dip in the saltpeter until sufficiently blued. ticles will reverse their course and dart (5) A great many of the chemicals and In- back and, as by a be gredients required, cannot be obtained from Remove and cool at once in Paraffine Oil. if stroke of magic, drug stores; buy them at a reputable supply Wipe with a flannel rag and dry in saw- instantly deprived of their motion and house. dust. vivacity. (6) BEFORE CONDEMNING A FORMULA, be sure the fault does not lie with the manner of Bluing Silver. -The oxidizing of silver A Rival to Jack Frost is produced by dis- handling it, or the purity of the Ingredients. is produced by placing the articles in a solving camphor gum in warm spirits until (7) Be sure to mix the materials comprising solution of Liver of Sulphur, diluted with the spirits will dissolve no more; a certain formula in the proper sequence. pour (8) When starting to prepare a mixture, Spirits of Sal Ammoniac. Allow to re- some of the solution into a cold test tube especially one containing liquids, ask yourself: main until the desired dark blue -black tone or tumbler and the camphor will instantly "IS THE SPECIFIC GRAVITY CORRECT, AS is produced; then wash in water, dry and in INDICATED BY A HYDROMETER? IS THE crystallize beautiful forms like trees and TEMPERATURE RIGHT? IS THE QUANTITY polish. landscapes. OR WEIGHT RIGHT? Durable Blue on Iron and Steel without This next experiment sounds as if it (g) Acids and water, when mixed, should be Heat. a stone pot and mix manipulated in the proper manner, i. e., THE -Take together were "bigger," but it is not. Dissolve 150 ACID SHOULD BE POURED INTO THE 1 part of a %-% solution of Red Prus- parts of hyposulphite of soda in 15 parts WATER, and not vice versa. as the solution is siate of Potash, 1 part of a t/ -% solution of water and pour the solution slowly into liable to be forcibly ejected from the containing vessel and Into the mixer's face. of Ferric Chloride. Dip the articles until a test tube or tumbler which has been (so) For any kind of SYSTEMATIC WORK, the desired effect is produced. When dry, heated in boiling water; fill the same about floating THERMOMETER and HYDROM- the articles may be lacquered. S. G. one -half full. Dissolve in another glass 100 ETER, as well as measuring glasses and scales, should always be provided, as GUESS- parts of acetate of soda in 15 parts of boil- WORK is EXPENSIVE, and SOMETIMES SYMPATHETIC INKS. ing water. Pour this solution slowly on FATAL. I give below the top of the first in such a (Ii) Put labels on ALL bottles, boxes and the formulm for making way that it packages with FULL INSCRIPTION as to their sympathetic inks: forms an upper layer, without mixing the contents, it will avoid troubles and mistakes. Formula No. 1. solutions. The two solutions are then (12) Remember that a beginner cannot expect covered to make articles AT FIRST, which will com- Take some pure lime juice, or lemon will over with a thin layer of boiling pare with regular manufactured products. do, and write with it on a paper. Then water and allowed to cool. Lower into the heat over an alcohol lamp and the writing test tube a wire, at the extremity of which FORMULA NO. 14. will come out brown. is fixed a small crystal of hyposulphite of BLUINGS FOR METALS. Formula No. 2. soda. The crystal traverses the solution of Blue Finish. -Clean the article very care- Dissolve some sulphate of iron in water acetate without causing trouble, but crys- tallization will immediately fully. Make a mixture 1 part of and write with it. Heat and the writing set in as soon of as it Nitric Acid, 10 Apply will come out dark brown touches the lower hyposulphite of parts of Water. or black. soda the liquid with a sponge until a blue film Formula No. 3. solution. When the hyposulphite of is produced. Wash with warm water; dry Dissolve some chlorate soda solution becomes crystallized, lower of potash in in with a flannel and wipe with Linseed Oil. water. Write with it and heat. The writ- the upper solution a crystal of acetate Bluing Brass Like leaden ing will come out brown. of soda suspended by, another wire and Steel. -Take a this will vessel, put in some Hydrochloric Acid and Formula 4. crystallize the same as the other No. solution. Contributed very little of Arsenic Acid. The brass For purple invisible ink. Take some by article is laid in this vessel and soon as- salicylate of soda and dissolve in water HAROLD B. FINKELSTEIN. sumes iridescent tints. Remove when the don't make the solution too strong, or it desired shade is obtained; wash with water will turn brown where you write with it. ANENT MAKING ELECTROTYPES. and dry. Reagent. 50 About per cent. solution of 1 notice in the August last number of Bluing Gun Barrels. -Dissolve 4% oz. tincture of iron applied with a brush. The the Electrical Experimenter, page 160, an of Hyposulphite of Soda in 1 qt. of Water. writing will come out purple. article on " \faking Small Electrotypes," Also dissolve 1% oz. of Acetate of Lead Contributed by ELLISON FRAZER. which, although excellent in its way, is in 1 qt. of Water. Mix the two solutions capable of much improvement. and bring to a boil in a stone pot. After Aluminum Lacquer.-For aluminum dis- Mr. Sutton says, "Three cells of bat- having thoroughly cleaned the barrel, coat solve 100 parts Gum Lac in 300 parts Am- tery should be connected in series to do with the hot solution, using a piece of monia, heating for one hour over a Water the plating." This seems not only absurd, sponge t:ed to a stick of wood. When bath, paint the thoroughly cleaned alumi- but wasteful. One gravity (Zn- Cu -Cu. color develops, wash with water, dry with num with the varnish and heat it to about SO,) is all that is needed. The writer a piece of flannel and finish with Boiled 570 degrees Fahrenheit. has made many electros (beginning in Linseed Oil. Polish for Varnishing ll'ood. -Shake 1801) and never used more than an E.M.F. Oxidizing Silver. -Boil the article in a well together 1 pint Vinegar, 1 oz. Alco- of one volt. 5 mixture of oz. of Bromine, 120 grains of hol, 1 pint Linseed Oil, 1 oz. Butter of Contributed by an "Old Experimenter," Bromide of Potas.Sium, 10 oz. of Water, Antimony. A. GALPIN.

www.americanradiohistory.com 286 THE ELECTRICAL EXPERIMENTER October, 1915

AMATEUR RADIO STATION key, sending key and aerial switch. With lowing: a % -kw. transformer, glass plate CONTEST. this transmitting set I have been heard up condenser, rotary gap (10,000 R.P.M'.), Monthly Prize, $3.00. to 200 miles; as far as Youngstown, O. with helix, hot wire meter and anchor gap. My receiving set, which was devised ex- For receiving I use a loading coil, loose This month's prise winner. coupler, two variable condensers, a fixed condenser, audion and mineral detectors. AN EFFICIENT EXPERIMENTAL The necessary switches are mounted on a STATION. panel. I present a picture of my wireless sta- When 2,000 ohm head 'phones are used tion which I should like to have appear in I am able to hear "N. A. A." and "N. A. your Radio Station contest. The instru- R." However, my 'phones are only wound ments, which are of my own make and to 1,000 ohms. My call is "8 V R" and design, have produced very satisfactory re- I would like to arrange tests with anyone sults. The receiving set comprises a within my range. loose coupler, two variable condensers, a I have read the Electrical Experimenter fixed condenser, loading coil, galena and since it started and enjoy it very much. perikon detectors, high -pitch buzzer and GEORGE C. CALVERT. 2,800 ohms head 'phones, mounted in a Pittsburgh, Fa hard rubber box which measures 12x12x 41/2 inches. W. On of the picture can be clearly RADIO STATION OF MORRISH. the right The photograph I submit herewith shows seen an audion detector set with two Hud- C. E. Watkin's Station. used my Canadian wireless experimental station son filament bulbs. which can be also which I used at Gravenhurst, Ont., Canada. as an amplifier. The front of the box is elusively by Prof. M. E. Packman, o 11x1ox a This station performed very good serv- made of hard rubber and measures Dodge's School of Wireless, consists of ice all around in both transmitting and re- 8 inches. In addition to this set, a vari- loose coupler, loading coil, variable and ceiving, and I hope shortly to send you ometer is employed which increases the fixed condenser, two galena detectors and photograph of my new radio station in sensitiveness of incoming signals. I hear phones. Opposite the receiving set can be seen England. a large loose coupler. As may be seen from the photo, the which is employed for long transmitting set comprised the usual helix, wave lengths and which can a spark gap, "Auto" ignition coil, key and tune up to 10,000 meters. condenser.. A specially arranged D. P. Mounted above the latter outfit is a wave meter built by Prof. Packman and my- self, composed of variable condenser, inductance, buz- zer, lamp and detector. My aerials, of which I have three, constitute, re- spectively, a flat top 81 feet high at one end, 60 feet at the other by 94 feet long, and umbrella composed of eight wires and a one -wire aerial. After four years of ex- perimenting I can now ob- tain very satisfactory results with this station and can hear "N. A. A.," "W. S. L.," 'il liam Morrish and His Canadian Station. "N. A. R.," as well as other Kaplan. stations very well. My call is Prize Station of Louis A. "9DI," and I would be D. T. knife switch mounted on the center pleased to communicate with of the panel -board over the table switches range. the aerial and ground connections from NAR, Key West, NAX, Colon, and a anyone within my and Ashland, Ky. C. E. WATKINS. transmitting to receiving, vice-versa. number of long distance stations. The receiving set included a home -made My aerial is 45 feet long, 40 feet high loading coil, which is seen mounted on the No. 14 copper wires GEORGE C. CALVERT'S WIRELESS and consists of four SET. wall at the left, also a large size loose spread 2 feet apart. My transmitting set inductance, os- I herewith submit a picture of my radio coupler with auxiliary tuning is composed of a 14 -kw. transformer, as well as variable condenser of the tubu- cillation transformer, stationary and set for the Amateur Wireless Station con - est. My aerial is made of No. 14 copper lar type. Crystal detectors were employed rotary spark gaps, glass plate condenser as well as others. and a heavy sending key. Owing to a low W. MORRISH. aerial, my sending range does not extend Mutley, Plymouth, England. very far, but I am heard clearly up to 20 and 30 miles. LOUTS ARNOLD KAPLAN. GREENFIELD, MASS., RADIO CLUB Bronx, N. Y. IS FORMED. At a meeting held recently at the Postal AMATEUR WIRELESS STATION Telegraph Cable Co.'s office, the manager OF C. W. WATKINS. of the company, Costas S. Theofan, Herewith I present photo which depicts brought about the organization of a wire- my radio station and which I hope will less club in Greenfield, Mass., and it is named the Radio Club. The appear in the radio station contest columns George Calvert and His Effective Wireless Greenfield of your valuable magazine. Set. club was formed with a membership of 15. For sending I use a 114 K. W. trans- The following officers were elected: Pres- former, oscillation transformer, aerial wire, 200 feet long, 75 feet high, on ident, Arthur Duchemin; vice -president, loading inductance, rotary and quenched spreaders 5 feet wide. Howard S. Wing; secretary and treasurer, gaps, condenser, hot wire ammeter, relay My transmitting set comprises the fol- Costas S. Theofan. Communications from

www.americanradiohistory.com 287 October, 1915 THE ELECTRICAL EXPERIMENTER amateurs within 20 miles from Greenfield of Famous Inventor club. Radio Station are solicited by the that catch A few of the mcmbers are: Albert Herewith I submit photograph and de- students have wireless receivers Karner, Rolland Stratton, Brenton E. scription of my wireless experimental the news. Technology camp has its own Donald N. Dins- post -office, Technology, and is located on Perry, Raymond Holden, station. 1 more. The members of this club are mostly The receiving station outfit consists of a Gardner Lake, East Machias, about eight are cxperimenting with wireless loose coupler by means of which 1 tuiles by road from the village. It is a boys who large work telegraphy. Albert Duchemin, of 26 Pond can get very accurate tuning, an Audion summer school which transfers the street, was the first of the local fellows to detector and variable condenser. The two of practical surveying and hydraulic meas- begin this line. sets of phones are usually connected in. urement from the limited city areas to the The transmitting set consists of a I kw. woods and ponds where actual work can Radio Station of Marcus G. Limb. specially made transformer, glass plate be donc on the commercial scale. Thcre transf mrmer, and a are about 100 students in the camp and a Herewith is given photo of my wireless condenser, oscillation % horsepower Gen- eral Electric Co. motor running a specially built, quenched - r o t a r y spark - gap. T w o. aerials are arranged. i / one for sending on / 200 meter wave ' " / length for distances /i ., 10 less than miles, i,' 1 and one for sending l' on 425 meter wave length for distances . G. Limb and His Radio Set. Marcus in excess of 10 miles. i II of t h e a Mur- Five plates / outfit. My receiving set comprises coddenser are used dock loose coupler, E. L Co. variable and meter loading coil, uni- for the 200 / adjustable condensers, wave length and 10 versal and crystal detectors and transat- are plates added to these lantic type 'phones. The two detectors 425 - receiving transformer. The five for the .... back of the meter wave length. following constitutes my transmitting set: 11 oscillation trans- The outdoor equip- A humming transformer, of a w former, oil -immersed condenser, spark gap ment consists with the ground 60 foot mast at 4 and a condenser in series a and . to reduce the wave length. one end t mast at I can send about 25 miles and on favor- 50 feet - :j the other, 100 feet : a able nights I can get N. A. R. My aerial 1 é Ii: 7" + /Tfi , t The spread- is 85 feet long, 50 feet high and has six apart. 10 long ,, wires in it. ers are feet . Wooster, O. MARCUS G. LIMB. and have 11 wires : of stranded copper ; Doughty Radio Station. between them. The The accompanying photograph depicts my ground connection i s carefully sol- located at Fairhaven, N. J' t radio station connected 4t. My aerial is of the inverted "L type and dered and consists of four No. 12 copper jacketed to ground at three . wires, 150 feet in length, spaced 2% feet places. This station apart. It is supported by an iron mast 75 can "work" points qi_: feet high and the lower end is attached to in Southern N e w T f a pole 45 feet high. The lead -in is 50 feet Jersey, Northern ¡# a n d in length and is taken in at the back of the Massachusetts ../ building through porcelain tubes. My can receive Colon, ground wire is connected to a water pipe Panama and ships which is driven into moist ground at a at sea, when two or depth of 12 feet. three days out of .....-'~ For receiving I employ Brandes' 2,000 - New York. The ohm receivers, Amco receiving transformer, station holds a spe- silicon and galena detectors, fixed con- cial license for the ii purpose of r e l a y work in the Amer - ican Radio Relay League. The call (=E letters are 1ZM. _Ai -1. HIRAM Efficient Wireless Experimental Station and Aerial of Hiram PERCY MAXIM. Percy Maxim. Hartford, Conn. score of professors, and the students have WIRELESS AT MASSACHUSETTS in commission two wireless receiving sets. "TECH" CAMP. Far down in Maine, where the morning newspapers of the great cities are not re- RADIO CLUBS ATTENTION! ceived till after nightfall, the students at the Massachusetts Institute of Technology We are always pleased to hear surveying camp have the baseball scores Mr. Doughty's Wireless Outfit. and news items posted on the bulletin be- from young Edisons and Radio fore breakfast. In fact, it would be pos- Clubs. Send a write -up of your denser and two loading coils of my own sible to post these items at night Club with photos members construction. before of and the presses of the city papers have begun apparatus to -day to: Editor "Ama- My sending set consists of a 1 -inch spark their work of printing, but for the fact teur Gossip" Section, coil, condenser and zinc spark gap, which that the receipt is after camp hours at The Electri- is mounted on top of my coil case. night and there would be no one astir to cal Experimenter, 233 Fulton St., JOSEPH H. DOUGHTY. read the bulletins if posted when received. New York City. Greenwich, Conn. This touch with the world is because the

www.americanradiohistory.com Ac1TE5T 1TENTS

Automatic Telephone Switch. The well -known "Crystaloi" de- a battery, choke coils S S, and tele- placement of the target at an angle (No. 1,145,632; issued to William C. tector now for sale on the market phone induction coil T. The primary with the plane determined by the Ude.) for some time. It employs two elec- of this induction coil is hooked up cathode axes. These features and An automatic telephone switch, so trodes A and B; the former having with a microphone of the usual pat- others of more minor importance, designed that the pressure of the a piece of sensitive mineral, such tern M, and a battery E. The reg- accomplish the fundamental object ear against, say a watch case re- as the best grade natural galena.. ular high frequency radiophonie of the invention; that object being ceiver 8, on a pivoted arm 6, will The electrode B consists of a mass current charges the antenna through to provide a tube capable of oper- conductive mate- ating with alternating currents and of finely divided /2.92 rial, such as aluminum- bronze fil- AV/ _ .t having a single focus point on the ings or they may be carbon grains, target. etc. These mineral electrode mem- bers are carried in a rotatable casing Electrical Umbrella Fan. C; so that the detector is quickly (No. 1,148,332; issued to Sylvester readjusted, by simply turning the Onyskow, assignor one -half to container on its axis, between two Lubomir Dulikrovich.) supporting springs, as perceived. Thus, a number of sensitive contact This invention covers the use of points are practically always avail- a small, electrically driven fan, as able with this ingenious form of de- i perceived and to be utilized in um- tector construction. brellas. The fan blades are driven by a small shaft, passing upward through the umbrella handle and Electric Rain Signal. (No. 1,143,246; issued to Joseph J. Barrash.) A -useful device where a rain sig- nal is desirable. The rain is caught by the funnel 3 and passes through cause the switch spr ngs, as per- it into a catch pan 4, which over - ceived, to automatically control the balances the pivoted lever 5. When an oscillation transformer and cutting in and out of circuit of the rain falls and actuates the lever, it the high frequency generator G. telephone transmitter and receiver, releases a sliding catch 10, con- The condenser transmitter is shown instead of having to hang up the re- nected bj a spring or otherwise to at Z. ceiver in the usual way. A very good idea. Heat -Shield for Incandescent Lamps. Wireless Receiver for Lighting Circuits. (No. 1,145,837; issued to Edward No. 1,143,799; issued to Ross B. Redmond Hoff.) Avery.) This invention relates to the pro- An ingenious wireless receptor, vision of a glass vacuum chamber t. claimed to work on lighting lines by around the regular incandescent lamp its inventor. The wires 3, connect B'. The idea is to prevent excess- with an ordinary alternating current ive heat being projected from the lamp, especially when used in close proximity to a person reading, etc. a sp ing switch 15 which closes the battery circuit for an electric alarm bell 18 or instead this circuit may stem, as is evident. This shaft con- control an electric motor for closing nects with a miniature electric motor windows or skylights. 28, which receives current from a small flashlight type battery 29, in the handle of the umbrella. A push Sound Enunciator. button 34 controls the battery cur- (No. 1,145.554; issued to Francis rent to the motor. The expense in W. H. Clay.) High -Frequency XRay Bulb. making up this arrangement and The inventor of this sound enun- (No. 1,147,125; issued to James E. also considering the gross efficiency, ciator arranges to have the dia- Seeley). and especially the small "breeze phragm A kept in a constant state This invention relates to a double producing power" in this case, does not seem to warrant at all the ex- 3 of high frequency vibration by using cathode X -ray tube for use with for instance, a superimposing mag- alternating currents, irrespective of pense in making up such an ar- 1 netising coil D, containing in its ex- their method of production and es- rangement. lighting or power circuit. The cur- citing circuit a source of electric pecially with alternating high fre- rent then passes through primary 2 current E, and a very high -speed in- quency currents. Electrical Insulator. and secondary 5 of a step -up, high - terrupter F. It is claimed that if The present invention consists (No. 1,146,201; issued to Silvester potential transformer. The current the diaphragm A is thus maintained fundamentally in the combination Nunn.) from the secondary transverses the of a pair of cathodes and a single small spark gap 6 and charges an target, in such arrangement that electro- static plate arrangement 8 both cathodes may focus on and F'rg.l Fig.2. and 10, separated by an insulating bombard the target at a single focus plate 11. Whenever a sufficient point. This invention is effected by charge acts between the plates 8 and an arrangement of both cathodes on 10, the plate 10 is attracted and in the same side of the plane of the its movement actuates a switch 19. impact face of the target; and the which in turn closes a local sounder arrangement necessitates relatively circuit 22. It is claimed by the in- angular positions of the cathode ventor that this arrangement will work on A. C. circuits and in ad- justing the device the spark gap 6, is so regulated that the ordinary in a constant state of vibration, at a current from the secondary 5 will frequency above audibility, that the not jump the gap. Then when any ordinary sound waves to be repro- wireless waves superimpose on the duced by the diaphragm from the A. C. circuit and reach the appa- telephone line coil C, in the usual ratus, they will boost the current way, will be much clearer and freer sufficiently to jump the gap and from distortion or false tones than thus actuate the sounder 24, as evi- in the usual way, where the dia- dent from the foregoing. phragm is allowed to vibrate by itself. Improved Mineral Detector. A new and simple form of in- up (No. 1,144,399; issued to Eugene T. Condenser Transmitter for Radio- sulator, intended to be made of Turne".) telephony. porcelain or glass. This insulator, so the inventor claims, is very effi- (No. 1,148,827: issued to Walther cacious for telegraph and telephone Burstyn.) lines, especially; and the wire is A modification of the condenser not clamped in same, but is simply transmitter, at one time used by retained in the insulator in the slot Prof. Fessenden for radiotelephonic 13. A threaded cap 15 screws down antenna current control. This pat- on a stud 11, forming part of the ent covers a multiple disc condenser insulator base 5. Thus the wire transmitter, as drawing shows. The once placed in the slot 13 cannot dielectric spaces between the various get out of same. The patentee claims metallic discs are varied and con- that a long length of wire (even a

jointly the electrical condenser ca- I mile or more) can be tightened up pacity, by creating various degrees axes, these axes intersecting at the without touching any of the indi- of electric charge on the plates, point of impact on the target, and vidual insulators along.the line, due through a circuit SIT, made up of also practically necessitates the to this novel construction. COPIES OF ANY OF THE ABOVE PATENTS SUPPLIED AT 10c. EACH. 288 www.americanradiohistory.com October, 1915 THE ELECTRICAL EXPERIMENTER 289 Phoney Patents Under this heading we will publish hereafter electrical or mechanical YOU THREE DOLLARS ($3.00) FOR THE BEST PATENT. if you take ideas which our clever inventors, for reasons best known to themselves, your Phoney Patent to Washington, they charge you Szo.00 for the bave as yet not patented. We furthermore announce the grand opening initial fee and then you haven't a smell of the Patent yet. After they of the have allowed the Patent, you must pay another Szo.00 as final fee. That's $40.ao ! ! WE PAY YOU $3.00 and grant you a Phoney Patent PHONEY PATENT OFFIZZ In the bargain, so you save S43oo I 1 When sending in your Phooey Patent application, be sure that it Is as daffy as a lovesick bat. The Por the relief of all suffering daffy inventors in this country as well daffier, the better. Simple sketches and a short description will help as the entire universe. our staff of examiners to issue Phoney Patent on your invention to We will revolutionize the Patent business Immmedlatelyy and OFFER a jiffy. PHONEY PATENT OFFIZZ PHONEY PATENT ALMOST AFFIRMED BY 1. M. A. NUT "No. 69512." ELECTRO- MECHANICAL NURSE Applied to Feb. 37, 1926. Specifications Overlooked O those unconcerned and who care The phonograph (14) contains a record goes back to the kennel and the switch :tot, let it be known that I, myself, made by the mother of the child. A opens again, thus saving milk and current. unassisted and alone, have invented photograph of the mother (24) is placed All rights to this invention are retained, a peculiar worthyful and valueish apparatus to alleviate and circum- navigate the multifarious troubles of the housewife. This invention has the full sanc- tion of Mr. Roosevelt in his great crusade against race suicide, and I feel that I am to be heralded as the Saviour of the race. 'Tis true that the canine included in the de- sign is subject to more or less tor- ture for the time being. How- ever, I expect shortly to. be able to improve on this detail. The operation of this contriv- ance is as follows: The baby (1) wakes up and, not seeing its mother, starts to cry. (The mother no, doubt is operating the wireless telephone, back -fence type.) The II 11111 111 IIIIII111I[IIII1III IIIIIIII IIIIII voices actuate the microphone (2), MIMI UMW which is connected by wires (3-4) ...`I to the 'phones (5) clamped on the ears of the dog (6). The dog, naturally, knowing something is wrong, runs from his kennel (7), pulling out the sliding bar (8), to which he is fastened by means of the chain (9). This closes the switch (10), thus completing the circuits containing batteries (11), motors (12 -13) and the electric phonograph (14). The motor (12) rocks the cradle (15) by means of the arm (16) attached to an eccentric on the motor shaft. Simultaneously motor (13) starts the double compound duplex air - cooled pump (18), to which it is Phoney Patent Issued on "The Electro-Mechanical Nurse." connected by means of gearing (17). The pump forces air through pipe in front of the phonograph, so in case the including foreign and domestic motion pic (20) into milk tank (19), which in turn baby should look in the direction of the ture rights. forces the milk through pipe (21) and flex- voice it will see the photograph and, think- In testimony thereof I have riveted and ible tubing (22), thus supplying the baby ing same is its mother, will instantly fall soldered hereto my seal, this day, date un- with a stream of milk. asleep. known and unstated, in this slow old burg At (23) is shown the adjusting screw A safety valve (25) is used to adjust the of Earthquakerdom. I. M. A. NUT. which regulates the delivery of the milk to pressure in the milk reservoir. By his Attorney, the baby, and by this means it is possible to The dotted lines show the position of Witnesses: P. Carroll Moaner'', regulate the hose to give anything from a the switch before the dog leaves the kennel, G. O. BEP.TIT, Philadelphia, Pa. steady, forceful stream to a fine spray. and when the baby stops crying the dog DED ENBURIED, '3d.

SOLUTION OF "PHONOGRAPH" moisture and made Sayville dry as a Sara- CODE PUZZLE IN SEPTEMBER toga chip. ISSUE. Now that the skies have bathed Sayville about every second day all summer, the This Way, Boys, to the Maze, Follow German wireless station is again to blame. Me Around, Now Please Don't Get Dizzy, Soon We'll Be There. AN ELECTRIC SQUIRREL? Ooh, Such a Headache! A German who had not been in the country very long walked in'o a drug store BLAME GERMAN WIRELESS one day. he first thing that caught his PLANT FOR RAIN OR DROUGHT. attention was an electric fan buzzing No matter what happens, the German busily on the soda counter. He watched A wireless station at Sayville, L. I., is to it with great interest for some time, then, CE. blame, Sayville folk think. Last year, turning to the clerk, he said: when there was a memorable drought, they "Py golly, dat's a lifely squirrel vot you "In -Come Tacks." said the electrical effects absorbed all the got in dare, ain't it ?"

www.americanradiohistory.com 290 THE ELECTRICAL EXPERIMENTER October, 1915 - '; n 311.l N_ti, QUESTION

This department is for the sole benefit of the electrical experimenter. Questions will be answered here for the benefit of all, but only ."... . of sufficient interest will be published. Rules under which questions will be answered: h. Only three questions can be submitted to be answered. a. Only one side of sheet to be written on; matter must be typewritten or else written in ink, no penciled matter considered. . Sketches, diagrams, etc., must be on separate sheets. Questions addressed to this department cannot be answered by mail.

ENERGY EQUIVALENT OF 1/12 readily deduced from Ohm's law, which door aerial described in the March, 1914, H.P. ENGINE. states that the current in amperes equals Electrical Experimenter works very well, (328.) F. Efermeyer, Cleveland, O., asks the volts divided by the resistance in ohms. as used by the French engineer, Mr. P. about the equivalent power or energy in Some of these cells "drop" as low as 4,000 Dosne. 5,000 As foot pounds of a 1 -12- horsepower engine. to ohms in the light. to your second query on small size A. 1. A 1 -12- horsepower engine is aerial, which you propose to erect on top of capable of doing 2712.5 foot pounds of work PERPETUAL MOTION? a piazza roof, we are of the opinion that per minute, thus it will lift that number (332.) Harold Jackson, Woodbine, Ia., this will be all right for short range work of pounds one foot per minute, or another proposes a scheme whereby (apparently) undoubtedly, and you would not gain any- weight an equivalent height in that space of an electric motor is to be operated from a thing by placing the wires in this aerial any time. storage battery, while the motor in turn closer together than about 1% feet. drives a dynamo that is supposed to re- ELECTRICALLY DRIVEN BICYCLE charge the battery. TRANSFORMER QUERIES. A. 1. We know of no arrangement, (329.) Byron S. Human, Niagara Falls, (334.) J. Glancy, Mars, Pa., asks sev- N. Y., inquires about the practicability of II11111111111111111111tuuu11111111111111I1IIIIIIIIIBE eral transformer queries. utilizing a -horsepower battery motor for A. 1. A closed core wireless transformer propelling a bicycle. made up from two 1/2-K.W. (E. I. Co.), A. 1. This is quite impracticable. In No. 8050 coils, as you suggest, would have the first place, iié horsepower is insufficient Want to Swap? a capacity of most probably in the neigh-

to drive a bicycle and, furthermore, it re- If you have anything to buy, sell borhood of 1/2 . K.W. quires an excessive weight of lead storage or exchange and want to make A. 2. The No. 8050 coils give about 10,- cells for any appreciable length of run with sure of doing it quickly and at an 000 volts apiece, and if two of these are the proper horsepower. insignificant cost advertise in the used in making up the closed core trans- Experiments are being carried on with former the secondaries should be connected motorcycles driven by electrical power, but Scientific Exchange Columns up on multiple. A. 3. The difference so far nothing really practical has come OF in voltage ratio in of it. the transformer as you mention would have The Electrical no effect whatever on the primary fre- WIRELESS QUESTIONS. Experimenter quency, or, rather, the frequency trans- formation through O., asks the transformer, the (330.) Wynn Boydan, Medina, You will find advertised in secondary frequency in any case being several questions on radio matters. these columns: identical to that of the primary in cycles A. 1. We cannot understand why the per second. mere adjustment of a detector should neces- Photographic supplies, Phonographs, sitate such a great change in the inductance Wireless Apparatus, Electrical goods, - used in tuning. Bicycles, Motorcycles, Rifles, Gasoline TRANSMITTING You must have made some change in the Engines, Microscopes, Books, Skates, CONDENSER QUERIES. capacity of your aerial to cause this marked Typewriters, Etc. (335.) K. K. Knaell, Mars, Pa., asks effect, as detectors have little or no effect several questions on radio transmitting con- The owners of these things wish densers. on the wave length. to "swap" them for something Your suggestion for a new loose coupler A. 1. Undoubtedly the E. I. Co. No. 530 else, something which you may condenser is correct is not exactly new and possesses no ad- have. as regards its electro- vantage over modern types. In winding static capacity in M. Fs., which, of course, the two coils so close you practically de- The corresponds to the value as given in their stroy all selectivity, which is the secret of Rates O catalog. The highest capacity is obtained the operation of the loose coupler. The One cent per word (name and when the metal rod is pushed through all of plan will work, we admit, and the coupler address to be counted) minimum the switch posts. will produce louder signals under certain space 3 lines. Average 7 words A. 2. The condenser you have should circumstances, but for all around work use agate to the line. Remittance give ample capacity for your wireless traps - your present loose coupler. must accompany all orders. mitting outfit with rotary spark gap, and The adopted method of shortening the the best capacity to use in the rotary spark wave length of an aerial is to connect a The Classified Columns of the gap oscillatory circuit should be found by variable condenser in series. This is done ELECTRICAL EXPERIMENTER varying the condenser switch until the on shipboard when the "distress signals" GET RESULTS maximum radiation current is obtained on are sent out and all stations with the long hot wire ammeter in series with the aerial, etc. wave require a series condenser to pick up More than 40,000 Electrical Ex- short waves. We know of no instruments Regarding the formula as cited in the imp perimenters will see which will eliminate excessive static with- your ad. "Electro" wireless course for the proper out also weakening to a certain extent the slllllllllllllllllllllllllllllllllllllllllllllllllllll' capacity of a wireless transmitting con- wireless signals. The only way this static denser this is used in the regular way for may be done away with to an appreciable such as we presume you have in mind, a rotary gap, excepting that function "F," extent is to shunt a variable condenser whereby an electric motor can be operated or the frequency value, is taken (for rotary across the coupler secondary, which dis- from a storage battery, and which motor gaps) as one -half the number of sparks sipates considerable of the static. will in turn drive a dynamo which recharges per second given by the rotary gap. This, the battery. This is physically impossible. of course, you can readily deduce from the SELENIUM Remember that the electrical and mechan- number of points on your spark wheel and CELL CURRENT. ical losses encountered in overcoming the the speed of the motor. If no rotary spark (331.) L. C. Yeaw, North Adams, Mass., frictional and resistance effects reacting on gap was used in your set then the function wishes to know the current that will pass such a system absolutely precludes any pos- F," or the frequency, in the capacity for- through .selenium cells. sibility of "making" energy, resulting in mula under discussion would be taken to A. 1. The current that will pass through what would really be "perpetual motion." mean the frequency of the alternating cur- selenium cells varies, of course, with the rent in the primary and secondary circuits resistance of same, and the cells regularly RE SMALL RADIO AERIALS. of your step -up transformer. This con- furnished all have different individual re- (333.) Patrick J. Leary, Boston, Mass., siders that there will be two sparks per sistances in most cases. inquires about indoor aerials. cycle of current. At any rate ,the current in amperes is A. 1. We understand that the special in- The rotary spark gaps usually cause the

www.americanradiohistory.com October, 1915 THE ELECTRICAL EXPERIMENTER 2yI condenser capacity, used in the spark gap oscillatory circuit, to be much reduced, as the spark frequency is, of course, raised very appreciably. Four hundred to 500 sparks per second are quite common with - such gaps. For best results with such gaps Multi u i -one a synchronous A. C. motor should be used to drive same, of course, so that the sparks will take place at regular periods with rela- The New Wonder in the Wireless World tion to the rise and fall of the alternating current wave in the primary and secondary This instrument increases the audibility circuits of the transformer. However, non - ONE THOUSAND FIVE HUNDRED TIMES synchronous rotary spark gaps are widely Remember that the Multi- Audi -Fone used and very good results are obtained will work equally well with all detectors. with them, all things considered. including the Audion, and when used with any wireless set will double and even triple the distance, and renders 5 K.W. TRANSFORMER ON audible hundreds of stations that you 3 K.W. ALTERNATOR. can get in no other way, bringing out all (336.) R. A. Bawles, Columbus, Ga., nearby stations, as well as those has a regular lighting type a.c. transformer thousands of miles away. and wants to use it for wireless transmit- Price, $30.00 ting purposes. SIGNALS CLEARLY HEARD AND ACCU- A. 1. If your 5 k.w. transformer of commercial pattern is of the high voltage RATELY READ WITHOUT HEAD -SETS The mplification is so great that when two type, giving 10,000 to 15,000 volts, it will Multi-Audi -Fones are used in tandem and a be serviceable for radio transmission pur- horn is attached to the receiver, the signals poses. can be heard all over the five story building MULTI -AUDI -FONE from our laboratories which are located on You could not, of course, operate same the third floor. If the windows are opened, The exact measurements of this instrument are 41/4x3x2'4 at full activity with a 3 k.w. alternator, the signals can be heard across the street, inches. Weight. 12 ounces but if -he voltage of the a.c. dynamo and even when the trolley is passing. the transformer primary correspond, you will get your secondary voltage correctly; It increases the audibility but the net output of the transformer will one be controlled by the output of the a.c. gen- erator naturally. thousand live hundred times It is possible to use lower secondary This instrument is indeed "much in little.' voltages from the transformer than those MULTUM IN PARVO It is a marvel of efficiency and camnaetntss, above mentioned under certain conditions, for it combines the CRYSTALOI DETECTOR and this matter, of course, is something we (Much in Little) which is superior to any other. with a COM- cannot speak definitely on, as you do not PLETE AND PERFECT RECEIVER. state what secondary voltage the trans- gives. The Crystaloi Detector especially designed for former us becomes far more sensitive when used in combination with our Multum in Parvo. This A. C. HOOK -UPS AND compact little instrument has a wave length AUDION ACTION. ranging from 50 to 3,600 meters, and will go into your vest pocket. (337.) John B. Moore, Downsville, N. Y., asks about three -phase "star" and Price, $20.00 "delta" connections. A 1. By the term "star connection" in These instruments in combination have a alternating current work is meant that con- receiving range of 3,000 miles. They are nection used for three windings on a three- The exact measurements of this instrument are beautifully finished in triple nickel plate fitax á inches, and made of hard rubber composition.

One Hundred of These Outfits Sent On Free Trial Naturally we must follow the rule of first come, first served. Therefore, if you do not get your outfit at once you will understand that there are others ahead of you and that you will get yours when your turn comes. Offer to Radio Clubs or Others We will send, at our own expense, one of these complete outfits to any radio club or any two persons. If you want to try this newest and greatest wireless improvement. sign the follow- ing letter. Have it guaranteed by your father or some other responsible man, and we will send the outfit to you on trial. Alternating Current Circuit Hook -ups, at "A" the Star Connection; at "B," Delta. MULTI- AUDI -FONE: 273 Morris Ave., Elizabeth, N. J., 1915. Gentlemen:- Please send us, at your expense, one of your complete outfits upon these conditions: phase alternator, motor First -We agree in no way to mar or injure any of the instruments by taking them apart. Second -We or transformer, rgree to repack carefully any of the instruments we do not buy in the same box in which we received whereby the three windings, when hooked them. The prices of these instruments are understood to be: Multi -Audi -Fone, $30; Muitum in Parvo, up. appear as in diagram A herewith, 29. HeadSet, $5; the outfit, $55. Third -We agree to remit within ten days of receipt of the instru- which resembles a star, as you will note. ments for such of them as we decide to purchase and to repack the rest as above agreed, and return the same at your expense within ten days after they are received by us. The other connection widely used for Very truly yours, similar purposes in alternating current Two Signatures work is that known as the "delta," shown are required (Name) Address in sketch at B. No apparatus A. 2. Relative to the ratio of turns in the will be sent (Name) Address primary and secondary windings on unless respon- the magnetic detector; there are several sible person I hereby guarantee that the above agreement will be faithfully kept and performed hundred turns on the secondary coil which signs this would have the same resistance (approxi- Guarantee (Name) \ddress mately) as the head 'phones in used con- SIGN -TEAR OFF -MAIL TO -DAY nection with same, and the primary wind- ing contains several dozen turns of heavier Send For Our Circular. Correspondence Solicited. wire. The secondary is usually about No. 32 MULTI -AUDI -FONE Mar is Avenue, Elizabeth, N. J. or 34 silk insulated magnet wire and the You benefit by mentioning "The Electrical Experimenter" when writing to advertisers. www.americanradiohistory.com 292 THE ELECTRICAL EXPERIMENTER October, 1915 primary about No. 24 silk or cotton in- sulated magnet wire. TFieNEW YORK A. 3. The principle upon which the TELEGRAPHY ELECTRICAL Audion detector operates is that of caus- ing a variation or change in the absolute and WIRELESS SCHOOL value or strength of a stream of electrons. A variation in this stream of electrons (as (11 The confused condition of the corn- produced in the Audion bulb by the in- 71 mercial world has created a vast in- crease in the use of wire and radio. We candescent lamp filament in same) is believe that students who start now will created by a trigger action. This trigger reap the advantages of great opportunity action is carried out in practise by means created by the war. of a wire grid and a metal plate placed in (1f Send us loe. (now) Ì our book on l' legraphy and Wireless ass an Cc. the proper position about the incandescent cupation.' filament. The grid and the plate are con- nected up to the Hertzian wave circuits of the radio receptor or receiving set. The BOSTON SCHOOL OF TELEGRAPHY incoming wireless signals in the form of 18 Boylston Hertzian or etheric waves thereby cause St., Boston, Mass. a change in the electron stream produced in the Audion bulb, and this variation in the quantity of electrons allowed to strike the plate in same is registered in a pair of sensitive telephone receivers connected to the plate in the Audion bulb.

Railroad or Commercial Telegraphy; RADIO OPERATOR'S SALARY. Learn Wireless individual instruction; five days and '1sRE N. Y. ELECTRICAL SCHOOL is the pioneer and four evenings per week: evening instruction. 55.00 per premier school of the Learn by Doing " method. (338) M. H. Chapman, Baldwinsville, month. Send for catalogue E. When you have completed this Course you shall be fully The PAINE Uptown BUSINESS SCHOOL qualified to handle ALL branohee of Electricalinduetry. N. Y., asks about the demand for radio 1331 Broadway. 55th Street, New York City The equipment of this School is unequalled and up- to-tb.. operators and the remuneration. 'nute. No preparation needed to become a "learner " in A. 1. is a chance this echool. You can start to learn on any day of any There at present good week throughout the whole year. Send for catalogue. for wireless operators, especially in view of Meet Your Personal Needs the great demand created owing to the If You want to specialize in some form of electrical New York Electrical School education suited to your need.. for a longer or shorter European war, which has taken many op- time. there is one place giving YOU boundless oppor- 29 West 17th Street New York City this of the world, and tunity. High school not required for thie work. Also, erators from side usual couree. to d Open nearly all the year. thus there are numerous openings both here Start almost any time Expert faculty. Cost low and abroad. now. Write for information to HIGHLAND PARK COLLEGE We We Solely On the average, a ship radio operator's President, George P. Magill, A. M.. D.D. salary is approximately $35 to $40 a month Des Moines, Iowa Guarantee Teach in most cases, which includes board and First Grade and medical attendance as well as berth. Commercial Specialize Land operators get from $75 to $125 a Operators' on Radio month, depending upon the station they are Licenses appointed to, and in most cases a percent- Telegraphy age or bonus is paid on the number of ric Li messages handled by the operator, which on shipboard of course depends a great LEARN WIRELESS deal on the personality and abilities of the Your H SEE THE WORLD operator himself. Lini- Lectric lighting plant gen- erates standard 11u -volt direct current; operates from one to 50 AND LODGE-MUIRHEAD lights, electric motor, electric iron, MERCURY COHERER. vacuum toaster, GET PAID FOR DOING IT orcppump, churo, washing machine, (339.) L. Bosserman, Pleasanton, Kan., etc. Last year every one of our graduates success- fully passed his required commercial Govern. No Batteries -No Switch -Board ment Examination upon the first trial. These and a machine for less money. High results speak for themselves. Send a stamp for new fall prospectus. Fall classes, both day a cdvernegovernor, alllloet noemllom-nsa,cm and evening, start Oct. 4. pactunit. Uses standard lamps and fixtures. Si mple, easily installed. dependable, economi- cal. Costs lee. than other systems to buy and Eastern Radio Institute to operate 899 B. Boylston St., Boston, Mass. Waterman Motor Company lit MT. ELLIOTT AVENUE with training are demand. The Bliss DETROIT, MICH. ELECTRICALinElectrical School, with Italife -equipped shops and course ins, is peculiarly Write to-day for well qualified to vive a condensed course in ller [risse full description Lec'tric and low price. ENGINEERING LIGHTING * SYSTEM e tteincluding Theoretical and Practical Electricity, in all branches. Students construct dynamos, install wiring and test efficiency of electrical ma- Mercury Coherer Hook -up. chinery. Course. with diploma, complete is interested in the Lodge- Muirhead Tner- IN ONE YEAR cury coherer. For practical young men with 1. the construction of a 1201(11M en'.ira'ned limited time. 23rd year opens Sept. A. Concerning 22nd. Write;f or new catalog E. Lodge- M'uirhead mercury coherer, the Special 6 months Evening Course n brass wheel used in same may be about "Wire and Wireless Operating rI 1 inch or more in diameter, or even less, 200 Kinds Iron, Wood, opens November lath, 1915. An and the number of teeth is immaterial. It Wire & Steel Puzzles Exceptional Opportunity is by a belt or otherwise at fair Catalog and Sample, 10e. o qualify as s rotated 3 Leaders for 25c. speed and the teeth of the wheel should WESTERN PUZZLE WORKS First Class Commercial Operator Dept. 30 St. Paul, Minn. Writ, for just barely touch the mercury. is easily 260 Takonea Avenue. WASHINGTON. D.C. This adjustment, of course, very ascertained when trying out the detector in You May Lam Theory, Code and / Laws of Radio Communication 1, the regular wireless circuit. The rotating In Our School or at Your Home, on TELEGRAPHY OPERATION tooth wheel should be movable vertically rfitting you for positions paying good sal- a else the mercury cup should be aria. with wonderful chance to travel th by retired railway officer. Railway wire. In slide or world over. It's the most interesting pro- advanced room.. E pen... earned. All graduates to height. fession direct in the telegraph service. adjustahle as known and the domand for skilled placed con- Operators is increasing. Send .tamp for oat- for Folders and Rates Diagram is shown herewith for the Io- ..hich rives toll ìninrmaNnn Send nection of this mercury coherer and regu- Peltier School of Telegraphy, Madison, Wis. NATIONAL RADIO SCHOOL, I5U2 lar tuning coil, condensers, etc. It has a Washington, D. C. America'. Scientific Roils.. Training School receiving range on par with other coherers. You benefit by mentioningl`.rTáe Electrical Ezperimente' when writing to advertisers. www.americanradiohistory.com October, 1915 THE ELECTRICAL EXPERIMENTER 293

A. C. GENERATOR DESIGN. SUPER -SENSITIVE (340) Fred V. Bechtold, North Man- chester, Ind., asks several questions on alternating -current generator design. 2100 MILES A. 1. In reference to your small al- ternating- current generator, the armature FOR SIX DOLLARS volts developed by same is dependent upon three main factors, viz.: upon the flux in lines per square inch of field -pole cross- sectional area; upon the number of arma- READ THIS ture conductors per slot (and total con- ductors, of course), and the revolutions per minute at which the armature is 1111o, Hawaii, T. if., July 14, 1916. rotated. CPG F,NE T. TURNEY CO., New York City. Dear Sirs -After having tested your Crystalol type AA You will thus see how it is possible to Wireless Detector for two months on both the Atlantic and Pacific sides, under all conditions which wire- increase the voltage on your alternator by practically CR Y STALO I DETECTOR varying any of these factors. If you desire less is subject to (static, freaks, etc.), 1 feel It my duty to tell you of a few "stunts" that 1 have accomplished TYPE AA to keep the speed of the machine the same, with it. $6.00. and also the number of the armature con- On May 29, while 915 miles south of Scotland Lightship, Weight, Two Pounds. copied all of W S T (Miami, Florida) press through static which was heavy. The signals came ductors, then you have only one alternative, ill clear and strong. The steamer 'ilonolulan" then about 100 miles to the south of us was unable which is to increase the field -flux density to hear W S T on account of heavy static. 1 gave him a copy of the press. more On Jnne 2 at 1 a. m. copied Blinn-Ws press while on the Pacific side, about 370 miles west of per square inch. This means that Balboa, Canal Zone; signals were clear and strong and did not fade as Is usually the ease with powerful magnet coils must be used in the most all other Detectors. This was a distance of 1,010 miles, over part of Central America and manner you suggest, and it is doubtful the Gulf of Mexico, and was accomplished through quite a heavy static which is prevalent in the Tropics at night In the summer. whether there is room on the field frame On the next night, June 3, 1 again copied aliamrs press at a distance of 1,%10 miles. The to do this. S.S. "Kansan" at that time was about 100 miles away and he could not hear W S T at all and said that the Matte knocked his point. But my Crystaloi was not in the least affected by the We would refer you to any book on the heavy splashes of X. subject of dynamo machine design for the July 9, while at anchor in Kahului harbor, Hawaiian Islands, copied 1C P 11 San Francisco data you desire, and several good books press at a distance of 2,110 miles, which Is extremely good work for this time of the year. I am more than pleased with your Detector and would recommend It to anyone who desires on this subject are handled by our book Detector for extreme long distance combined with ease of Operation and simplicity. it does not department. You may use a storage bat- fall short one point in what you claim for it. Wishing you continued success, I am, for exciting the field as you mention. Respectfully yours, A. H. RANDOW, Operator S.S. "Dakotan." tery Full Information In changing your field winding for low EUGENE T. TURNEY CO., Inc., 2595 Third Ave,, NEW YORK CITY voltage, the cross -sectional area of the cop- per wire for the coils is increased propor- tionately as the direct ratio of the new voltage compared to the original voltage rating for which the coils were designed. Also for the low- voltage winding a pro- The "Midget" Gasoline Motor less number would portionately of turns BORE 21/2 " -STROKE 21/4" also be used. 11/2 H. P. Air Cooled, Light Weight. Two Cycle RESISTANCE AND DAMPING. Especially adapted for driving canoes (341) J. L. Green, Rosser, Man., Can., and rowboats. Developes sufficient power asks several questions on damping, resist- to drive dynamos up to 800 Watts output, ance, etc. washing machines, cream separators, grind- A. 1. The matter of loose -coupler ers, and all sorts of light power. Has wave lengths was explained somewhat in vanadium steel crankshaft, bronze connect- the September, 1911, Electrical Experi- ing rod, Lunkenheimer mixer valve, alumi- menter. The primary and secondary wind. num muffler, runs at a high rate of speed ings of the loose coupler when shunted by and is a perfect little whirlwind of power: variable condensers are considered as dis- The new prices for this engine, corn - tinct oscillatory circuits, and the regular pletely finished and ready to run, with wave- length formula is applied to them for exception of batteries, coil and gas tank general calculations. are as follows: We would suggest the % -inch thickness Stationary Engine mounted on maple of hard rubber for the small switchboard subbase and with 21,6 in. by 1% in. face you mention. The reason why, as you pulley $17.50 mention, some text -book writers and others Marine type Engine with 7 in. -2 blade often suggest loose couplers for wireless aluminum propeller $17.50 work having a comparatively small number in coin of turns to be counter -balanced by con- Send 25 cents stamps or for full denser capacity in tuning oscillatory cir- size blue prints of this engine. cuits, is due to the fact that if a great Remit by Postal or Express Money number of turns are used in the coils there Order. is also a high ohmic resistance encountered. etst This directly affects the "damping" of THE PRECISION MACHINE WORKS,308 Kansas City, Mo. the circuit, of course, as the greater the ohmic resistance of any oscillatory circuit the higher the "damping," and vice versa. LEATHER This EASIER WORK relation between the resistance of CASE BETTER AND CAN BE DONE BY USING the circuit and the damping is observed from the following formula for this func- Free "RED DEVIL" TOOLS Until you know them you don't know what tool satisfaction and tool tion as cited in Commander S. S. Robin - economy is. No. 1124 plier with screw driver and prest-o-lite opener son's "Manual of Wireless Telegraphy for mailed for 50c. Helpful tool booklet free. Write today. Naval Electricians" (1913 Edition). The SMITH & HEMENWAY CO., Inc. formula is: 153 CHAMBERS STREET NEW YORK CITY d- R 2nL YNOOLIWR BREE d ATTACK ANDU PREPARED where = damping of any circuit. Aller my 27 years work for U. S. and Foreign Go vernurien to and Iarro R =total resistance (high fre- ,roors,inns, I am in a position to offer you the cream of my life 'a ork. x Inch comprises the Best Course Ever Publicly Offered in quency value in radio circuit, which emhraeee Pr istic pa, Developments. of course) in ohms. I Chart Machine DeJ. 8. Machine Design CmCam 'Charts..NO s. Real Shopch ADV D. e. n = frequency of oscillations in cir- and Foreign Patent Eta. NO LARGE IN ADVANCE. PAY AS YUUYOU LEARN. NOTHING FREE. R'nteWrite (or Dnrtitulers. cuit. PERSONAL ATTENTION L = self- induction of circuit in Submarine "Technical Education" Preparing to DERSISEINSTRUCTION Attack the Obsolete Battleship "Ignorance" TIC A COACHING BY Consulting Engineer Henries. PERSONALRACTICAL ENGINEERS 10 Meigs Bldg.. Bridgeront. Ct. You benefit by nie, boning "The Electrical Experimenter" when writing to advertisers. www.americanradiohistory.com 294 THE ELECTRICAL EXPERIMENTER October, 1915

USE OF TWO LOOSE COUPLERS. Price (342) George Meister, Newark, N. J., asks for hook -up for two loose couplers $100 in a radio receiving station. A. 1. Diagram is given herewith for connection of two loose couplers, with the other usual instruments. In this way the second loose coupler serves as a duplex loading coil in both primary and secondary s The Royal is the typewriter with the Your Hands Can't Earn rapid -fire action and ad- the'Money,You justable personal touch - Need the machine that fires You'll have to work for low letters as an automatic wages all your life if you de- gun spits bullets! pend upon your hands to make your living. To earn more Built for the Expert money you've got to learn how Typist-Betterforthe to work with your head' you Ordinary Operator The new Royal way of sending must have special training for Diagram for Two Loose -Couplers. some particular line of work. direct force from the fingertips of the second coupler with a wide range to the type takes the "grind" of coupling. out of typewriting and increases And you can get this training without the daily output of any stenog- leaving your home or losing an hour rapher. from your work -the International Cor- TESLA COILS FOR RADIO WORK. Get the Facts! respondence Schools can bring it to you (343) Fred Kessler, Springfield, Ill., Send for the "Royal man" and right in your own home during your spare speaks of using a Tesla high- frequency coil ask for a DEMONSTRATION. time. They can train you for the very for radio -telegraphic sending circuits. Or write us direct for our new A. 1. This is not practical and it is brochure, "Better Service," job you want -where you can earn more never employed when the usual form of than enough money to meet needs. and a beautiful Color- Photo- your Tesla coil is considered. Of course, every graph of the NewRoyal Master - wireless transmitting set constitutes a spe- Model 10. If you want to advance in your present cial form of high- frequency Tesla or occupation, the I. C. S. can train you for Oudin coil, but the ratios of the primary ROYAL TYPEWRITER CO. Inc. promotion. If your present work is not and secondary windings of these wireless Rend Typewriter Bsildiet high- frequency coils is many times lower NEW YORK pleasant, the I. C. S. can qualify you for than those existing in regular Tesla trans- "J a good position in the kind of work you formers used for demonstration and ex- like best. perimental work. Solid Oak Letter File A. 2. The matter of aerial wave lengths ff Every month more than 400 I. C. S. was covered completely in an exhaustive As GOOD As Ever -At a BETTER Price No

LANCASTER;*- &ALLWINE B 252 Ouray Bldg. °C Washing on, D. C. Book "Inventions- Patenting & Promoting" Free Our co- operation with an inventor is. FIRST, to Edited by H. GERNSBACK help him establish his rights before he discloses the idea to ANY attorney. SECOND, to give a frank opinion matter as is of interest to inventors whether it will pay to patent his idea, based upon our In this Department we will publish such enteneive knowledge of manufacturers' wants and fooil- and particularly to those who are in doubt as to certain Patent Phases. Questions tiee. THIRD. to obtain for him a patent which is in and descrip- areality a valuable monopoly. FOURTH, to advise and addressed to "Patent Advice" cannot be answered by mail. Sketches ssist him in the profiting by outright sale. territorial Only one side of sheet should be written on. grants. obtaining royalty, or independent manufactur- tions must be clear and explicit. ing of the invention and FIFTH, aiding him to so profit by conferring with manufacturers, investors or Jietribu- tore of machinery. COST OF PATENT IN UNITED Before sending a sketch to anyone, sign, witness. DESIGN PATENTS. and deposit in our fire -proof vault our document (19) H. B. Meadowcraft, San Antonio, STATES. (22) Hamilton B. Lancaster, Lynn, Mass., EVIDENCE OF CONCEPTION Tex.. wants to know what a design patent AND ESTABLISH YOUR RIGHTS is, and what it costs to obtain one. wants to know what the Government fee (A%) Design patents may be granted is for a simple invention in the United States. THAT PAY" for any new ornamental design or article OUR TRADE -MARK of manufacture. For instance, you might (A.) When you apply for a patent of design a fork or spoon which has a new your invention there are two fees, the first OVER $600,000.00 MADE BY CLIENTS ornamental design which might be a flower Government fee when applying for patent or any other pattern which has not been being $15. When the Government has PATENTABILITY TWO WONDERFUL used before. In order to keep others from finally allowed the patent, a final payment REPORT BOOKS FREE; copying the design, one applies for a de- of $20 must be made to the Government Send sketch or model of Entitled '*Investors sign patent by submitting the design to the before the patent can be issued. In other your invention for free Guide" (146 pages) and patent office. Design patents may be for words, the total fee that the Government search of the "What and How to In- requires on any patent is $35. Of course, Office R and re- vent -Proof of Fortunes any new distinctive design or ornaments port ante patentability. in Patenta" (127 pages) which may be adopted on silks, fancy this is only the Government fee and does fabrics, cut glass, metals, emblems, jewelry, not include the fee of the patent attorney Highest References. including 100 manufacturers pictures, shapes and almost every other who prepares the papers, drawings, etc. article of manufacture. If a design patent Usually such a fee to the patent attorney PROMPTNESS ASSURED is obtained, the patentee has the right to varies from $25 upwards, all depending Across the Street from the Ue S. Patent Office mark the article patented which gives no- on how much work has to be performed, tice to his competitors that the same design how many patents must be looked up, and E. E. VROOMAN & gton, must not be used by others. authorities consulted, etc. A'n ordinary Design patents are granted for three patent with one sheet of drawings and and one -half, seven and 14 years, at the specifications that are not too complicated YOUR IDEAS option of the applicant, but it cannot be will usually amount from $25 to $40 with Under our plan extended at the expiration the period the average patent attorney. PROTEC T inventions can be of protected at low cost during financial strip for which the original patent was granted. gency, or while perfecting or testing commer- The Government fee for three and one - CAN SWITCH BE PATENTED? cially. Square deal proposition with refundable half years for a design patent is $10, for (23) Newell M. Ferris, New York, has fees and free investigation if you mean busi. nets. Send for free booklet and references. seven years $15 and 14 years $30. Full sent in a drawing and explanation of a Milo B. St & Co., Attys., Eetab. 1864 fee must be paid at the time the application new flush switch, and he wants to know 694 F St.. Wash.. D. C. 207 Iloaads «k Block, Chicago is filed. To this must be added the fee whether we would advise him to patent it, which the patent attorney will charge for also if there is a demand for such a switch, his work in preparing the specifications and and whether he ought to submit it to some drawings. These fees vary from $25 up- electrical manufacturing company in order PATENTS wards, all depending on how much work to get financial aid for patent. THAT PROTECT AND PAY is to be performed. (A.) While the device submitted is un- questionably novel, and while we think that Books and Advice Free Send sketch or model for search. Highest References. WIRELESS TELEPHONE TRANS- a patent might be obtained upon it on ac- Beat Results. Promptness Assured. MITTER PATENTABLE? count of the constructional details, we do WATSON E. COLEMAN, Patent Lawyer (20) I. Rosin, Cincinnati, O., sends in not think that it would be worth while to 624 F. Street, N. W. Washington, D. C. a sketch and description of a new wireless do so, as it appears to us that the device telephone transmitter which our corre- is entirely unpractical and has several fea- spondent claims can carry very heavy cur- tures that make it particularly undesirable. rents. He wishes to know whether the The biggest objection is a sliding move- PATENTS WANTED ment invention is practical and patentable. covering quite a little range and a Write for Our Five Books, sent Free to any (A.) The invention presents nothing necessarily large hole which thereby is address. "What to Invent" contains List of not known necessitated in order to move the handle Inventions Wanted, with full information re- so far, and while a patent might garding $1,000,000 In prizes offered for inven- be obtained on some technical points, we back and forward. tions, among which are doubt whether the device is satisfactory at We do not think it would be passed by $100.000 for Best Substitute for Gasoline. all, for is the Board of Fire Underwriters in its $50.000 for First Person Crossing Atlantic in it nothing but a relaying scheme Aeroplane. whereby the microphone operates a relay present shape and therefore would be $26.000 for New Substance for Denaturini, system which actuates another large ca- valueless. Alcohol. $50.000 for Best Device for Saving Life at Sea pacity form of microphone. It does not $10.000 for Machine for Pulling and Topping present a good solution of a heavy current ABOUT TRADE -MARKS. BeetS. carrying microphone such is (24) A.. B. JlcCann, Los Angeles, Cal., $10.000 for Automatio Train Control. as desirable $10.000 for Improvements in Postal Service by in wireless telephony. inquires about trade -marks, where used United States Government. and how obtained. $12.000 for Improvements in Navy Department (A.) A by United States Government. EMPLOYER AND EMPLOYEE ON trade -mark may be registered $10.000 for Improvements in Field Motor PATENTS. by an individual, firm or corporation in Ambulances. (21) H. Cabot, Boston, Mass., wishes the United States or in any country grant- $5,950 for Miner's Electric Lamp. to know if an employer is not entitled to ing similar privileges to citizens of the We have a special department devoted to Electrical inventions and having secured many the invention of an employee if the inven- United States when used in commerce with valuable patents in this class we are In a posi- tion has been made on the employer's foreign nations, provided it is a proper tion to advise tind assist inventora to this field premises. in the development of their Inventions. (A.) An employer merely by employing . -- -FREE COUPON! an employee is not entitled to the invention of the employee unless there is an express VICTOR J. EVANS & CO., Patent Attorneys contract to assign it to him. In other NEW YORK OFFICES: 189 -191 Broadway PHILADELPHIA OFFICES: 1429 Chestnut St. words, if no contract exists between the Main Offices: 779 9th Street, N. W., WASHINGTON, D. C. employee and the employer whereby the GENTLE RES: Please send me FREE OF CHARGE your FIVE Books as described above. former is to assign his patent right to the latter, it will be the property of the orig-

inal inventor. IM1 !Ne.me ee.aa..aa.a.a.a.a.=DR=55=1 OM MN a. !MI IM1 !MI !MI .a....a.

www.americanradiohistory.com 296 THE ELECTRICAL EXPERIMENTER October, 1915

subject for registration. long it will take for a patent to issue ónce THE Briefly, a trade -mark is a particular or applied for. It depends entirely upon how distinctive design by which the goods of much work is at hand in the particular de- the owner are distinguished from other partment of the patent office, also how goods of a similar class. No geographical fast the applicant's attorney will do the names or insignia of the United States, work. It happens not infrequently that a municipality, foreign nations or marks patent takes from six to eight years to which are descriptive of the goods upon issue for the reason that changes of claims, SQUARE which they are used can be trade -marked. amendments, etc., have been made after No emblem of a fraternal society can be the application has been made. Some used. The meaning of "descriptive of the patents have issued as soon as two months, goods" is that, for instance, you could not but such cases are extremely rare. HAND LANTERN obtain a trade -mark if you were a manu- We would say that the average patent HAS AN ADDED ADVANTAGE facturer of electrical lamps, and you takes from eight months to a year to issue Solidly built with double handles and wanted to trade -mark a picture of the after the application. equipped with the 3 -volt Nitrogen Radio lamp. This would be held as a trade -mark battery that produces the perfect range of light and gives three times the upkeep of descriptive of the goods. You might ob- SCIENTISTS WILL STUDY STRAY any other standard six -inch battery that tain a trade -mark of your own name if ELECTRIC CURRENT IN THE this lantern is made for. presented in a distinctive manner provid- ATMOSPHERE. ing it did not conflict with any already Wireless experts are congratulating existing similar name. themselves on the increased facilities now In other words, a trade -mark is nothing afforded for studying the by- products of but a seal which is used in order to brand nature's laboratory, namely, "strays" or or distinguish your goods from other "x's." The completion of the new and goods. It is also necessary that once a powerful radio station at Yokohama, trade -mark has been obtained, it cannot Japan, not only facilitates wireless com- be changed in any way. This is an im- munication across the Pacific but likewise portant thing to consider and should be opens a broader field for investigation of very carefully weighed before application atmospheric electricity. is made, for no change can be made with- Long -distance stations, due to their high out effecting the validity of the mark. power receiving apparatus, are best equip- ped to give data on etheric disturbances. Scientists located at San Francisco, Hawaii IS RADIO SCHEME PATENTABLE? and Yokohama will collaborate to reach a (25) S. Beecher, Campbell, Tex., sends definite understanding of these stray cur- in a sketch of a device to control ma- rents. chinery on a small boat by radio, and Dr. W. Eccles is at the head of the in- wants to know if it is patentable. vestigation, having been appointed by the (A.) Nothing new is contained in the British Association to carry on the work. idea; as a matter of fact, similar schemes Very little is known about the origin of have been shown repeatedly in this maga- Note the feature contact switch. Highly "strays" or "x's." They were given these finished nickel or black enamel. Carried by zine, and any text book containing some names for brevity, about 1887 or 1888, and all first-class dealers or write direct. chapters on radio tele- mechanics will show were more recently called "static." They a variety of such devices. are familiar to everyone who has worn INTERSTATE ELECTRIC NOVELTY CO. We do not think it is possible to obtain wireless réceivers in one or more of their 29-31 PARK PLACE, NEW YORK a patent that is worth while on this device. various forms. Chicago. San Francisco. Toronto, Can. It is natural that we should jump at the AN INGENIOUS LAND TORPEDO. conclusion that "strays" or static is due (26) William E. Egan, Troy, N. Y., to lightning, but this theory ignores the Special Dynamos submits an ingenious which is fact that they may be due to forces ex- for Arc Lamp in torpedo Moving Picture supposed to move under its own power terior to the earth. There is nothing un- Shows. Special Dy- from one trench to another. When arriv- reasonable in supposing that the sun may namos for Charging ing at the enemy's trench hundred send us occasional electric waves. S t o r e ge Batteries. several Special Dynamos for pounds of gun powder are supposed to The formation of spots on the sun or Incandescent Light- be exploded at any desired time by means the constant colossal changes of relative ing. We sell upon a flexible cable position of the various heavenly bodies payments of $5 and of electrical attached to the $10 per month. machine. may give rise to electric waves that reach Hobart Bros. Co.,Troy, 0 (A.) The idea is certainly novel and to the earth and cause these disturbances. It our knowledge nothing like this has ever is questions such as these that the British in Association is to solve, if possible. Experimental Work at Reasonable appeared print so far. While there are Prices several objections to a scheme of this kind, Another subject under observation is the TOOLS AND DIES it might prove of real use to countries at part played by the atmosphere in the varia- Light Machinery Designed and Built. Auto- tions of signal strength, these variations in matic Machines. Cams Cut Exactly to Templet war if all the details were worked out fully. One of the main objections of the relation to weather conditions, the time of GEO. SCHWARZ & CO. invention in its present shape is that it is day and with the position of such freak 123 Liberty Street NEW YORK too vulnerable, in other words, even a disturbances on the face of the globe. Send sketch or blue print for estimate small shell when shot at the machine would not only wreck it but blow it up, and if RECEIVING WIRELESS MESSAGES this happened near the trench from which WITH ODD AERIALS. Armature Discs it had been sent it would prove as deadly (Continued front page 274.) AT FACTORY PRICES to the sender as to the enemy. We think Any size from 234 inches to 14 inches in diameter. the invention is patentable, but we would odd aerials are used inside of a house no Best grade material with suggest to cover the machine with an in- results can be had unless the house is con- japanned insulation on verted "bath-tub" shape armor protector structed of stone or wood. A house con- one side. Send stamp for circular. in order that a shell fired from the enemy taining steel beams or a mass of other iron FRED. R. HEILMAN will not wreck and destroy the machine work will make the use of such indoor 444 Niagara St. Bet tala. N. Y. before it reaches its destination. We aerials out of the question. would advise our correspondent to get in We publish these suggestions not as a touch with one of the patent attorneys to mere curiosity, but it is thought that any Experimental and Model Work see what has been done in this art before. one of these schemes might prove of in- ELECTRICAL INSTRUMENTS AND HOW LONG DOES IT TAKE TO valuable benefit in case of emergency. FINE MACHINERY GET PATENT? Storms, a fire, sleet, etc., might put the Inventions developed. Special Tools. Dies, (27) Hamilton Brown, Springfield, Ill., regular aerial out of commission ; in that Gear Cutting, Etc. claims he has invented a new electrical bell case some of the above- suggested freak HENRY ZUHR on which he feels sure that a patent will aerials could be used to possibly good ad- 32 -34 Frankfort Street New York City be granted. He wants to know how long vantage. Note that most of these odd it will take him to obtain a patent once he aerials can be used for sending as well as the Classified Advertisements In this issue. They are small but contain has made application. receiving. For sending purposes they READ big bargains and opportunities. (A.) It is impossible to prophesy how should, of course, be well insulated. You benefit by mentioning "The Electrical Experimenter" when writing to advertisers. www.americanradiohistory.com October. 1915 THE ELECTRICAL EXPERIMENTER 297

BARON MUNCHHAUSEN'S NEW not possibly witness the reappearance of Mars had Income acute. The fertile lands SCIENTIFIC ADVENTURES. the polar snow fields, every Martian year, were fast turning into deserts for rains (Continued front page 248.) as we actually do. Where, then, does the had become more and more infrequent, water go? until they had stopped almost entirely. explored on this dead world. Besides, the "Dr. Lowell solved the problem in a bril- Furthermore, as Mars is flat without meteors had become so alarmingly frequent liant as well as ingenious manner. mountains or elevations of any sort, there that it would be only a matter of time when "His view-and it is shared by most of could not be any natural rivers to convey one of us would be killed. our scientists to- day-is that Mars is in- the water to the plains and valleys as is "Flitternix wanted to return to earth habited by a thinking people, fighting a the case on our world. The Martians, see- at once, for he itched to present a lecture heroic battle for their existence. With- ing utter extermination staring them in to the American Astronomical Society, out water, life, as we know it, cannot exist. the face, proceeded to save their race. whose honorary president he is. 1, how- Now ages ago the shortage of water had They did precisely the same thing as we ever, had more ambitious plans. I once made itself felt on Mars. Long before are already doing in Western America and had looked through the great telescope at the first cave man appeared on earth Mats the Egyptians are doing in Egypt, namely, the Lowell Observatory at Flagstaff, Ariz. had been an old world, where civilized irrigation of deserts or semi -deserts on a If I live to be a thousand years old I will peoples had reigned for centuries. While large scale. Our recent Roosevelt dam in never forget the glorious sight which then our ancestors were still jumping from limb Arizona offers a good example of this. presented itself to my eyes. to limb among the trees in primordial Our engineers on earth have to bring the f "I saw a ball, lighted up dazzlingly at forests and jungles, the water problem on water to the deserts, precisely as the both extremities. I saw great patches of an ochre red scattered over the surface of the sphere and I had seen dark blue areas among the vast ochre patches. Over the This Splendid latter runs a mass of fine lines, nearly all of them connecting with the white caps at each extremity. Moreover, these fine lines cause one to gasp involuntarily, for they are as straight and true as if laid out with LIBRARY of ELECTRICTIY a rule and pencil. More astonishing yet, some of these lines run absolutely parallel Free for Examination with other ones for the whole length of Sent their extent. And more wonderful yet, whenever two or more lines meet in a "WV Per Volume -Pocket Size -Leather Bound junction there is invariably a round black HERE is a set of books that no man in the ELECTRICAL FIELD should point. do without. This is the ELECTRICAL AGE in which we live; ELEC- "The ball I had been looking at trans- TRICITY now controls more trades, directs more men, offers more op- fixed for a long time was Mars, the near- portunities than any other power that man has yet discovered. Do you wish est planet to earth, then 37,000,000 miles dis- to knew the underlying principles of Modern Electrical Practice? tant from the latter. Prof. Percival Lowell, If so, HAWKINS ELECTRICAL GUIDES will give you the greatest living authority on Martian re- the information. In re- search work, has convinced the scientific ality they are a school world that the dazzling white caps at the within themselves, con- poles of this planet are the polar snow fields. taining a complete study The great ochre patches are desert land. course with QUES- while the dark blue areas represent large TIONS, ANSWERS tracts of fertile land and its resulting vege- (PRINCIPLES A N D ILLUSTRA- tation. ;ELECTRICITY - ,...__- . TIONS, written in plain 'Now, according to well -known physical MOTORS: : SYSTEMS everyday language so : MOTAnaORS ' laws, proved beyond discussion, the smaller NpU[T ÓN I.NSTRUMENI' STORAGE that a practical man can ARMATURE a body the quicker it will cool off. Ail !INoRIMENIS `. understand. - ::TESTING :: jBATTERIES planets and their moons once were white : DYNAMO ".: WINDING: The How, When and hot like our sun. The smaller ones cooled off first and the larger ones are not cold Why of Electricity as yet. Thus the earth, which measures Read over the titles 7,912 miles in diameter, is still red -hot in shown on the back of its inte:ior, as is proved by its active vol- each volume, and note canoes. The moon, which is but 2,164 miles ; f.;:...,w!' A.C. .. the scope of each book. across, cooled off ages ago. The oceans :;:, SWITCH' : They are handsomely once filling its beds then filtered down in IITRNATÍfJ : :SYSTEMS BOARDS. bound in flexible black its bowels, there to freeze solid, for there CIRCUIT % WIRING leather with gold CURRENTS :: edges .(fBAN,SF01 BREAKEAS POWER was no heat to keep the water fluid. Its STATIONS.' and will readily go in the ;(ÖNYEATEAS - ` atmosphere, which was formerly as dense MEASpRING ; pocket. They are not ALTERNAIORS INSTALLATION only the as that of our earth, was gradually thrown 'RECTIFIERS . INSTRUMENTS' OPERATION_:` best, but the off into space, till to -day practically no at- cheapest works pub- mosphere remains. Thus the moon to -day lished on Electricity., rolls on through space a dead world. c FILL OUT the "The planet Mars, measuring 4,363 miles Coupon now and /ptó` in diameter, as will be seen, is only twice get this practical ', education 04' as large as our moon and much smaller electricity in ss than the earth. Consequently it must be I WIRELESS' MODERN. "Written so rapidly nearing its extinction, the same as you can un- 4m6 i. ¡APPLIUTIO derstand the moon. Its oceans are already dry, ÉTEIEGRAPH '4 it." G while most of the land is desert. The at- ÈTELEPNONEt... Please 'ELECTRIC' . :. submit me mosphere has nearly all gone too, proved iI.IGNTINGS. fact that we practically never RÉFERENE for examina- by the ob- :; tion HAWKINS serve clouds on .Mars through the telescope. AILWAYS.;. pE il ELECTRICAL But there must be water on the planet as A NUMBER GUIDES. (Price $1 yet, this being proved by each.) irrefutably its Ship at once prepaid polar snow caps, This view is further the first eight numbers; strengthened by the fact that these caps "That's Just What I Need" if satisfactory I agree to seasonal changes. As send you $1 within seven undergo the sun days and to Each book is complete in itself, eight numbers nu, further mail you beats down upon them we see first the $1 each month until paid. ready, and will be supplied $1.00 per number, but we be. one, then the other, grow smaller in size, The lieve that the complete set is the best bargain. Signature till at the end of the Martian mid -summer books can speak for themselves and a careful exam- the northern one has disappeared almost ination, page by page, and illustration by illustra- tion, will convince you of their big value. If Occupation entirely. During the next hot season the coupon all , giving you will fill out the following A, Business same happens to the southern one. Where the information requested, we will submit the Q,Ob Address has this water -the only remaining water first eight volumes for examination on con.' named. p0 Residence on Mars -gone? It cannot have filtered ditions E. EXP. into the interior, for if it had, we could .t Reference You benefit by mentioning "The Electrical Experimenter" when writing to advertisers. www.americanradiohistory.com 298 THE ELECTRICAL EXPERIMENTER October, 1915

'Martian engineers must have been doing it for centuries past. LEARNING TELEGRAPHY YOUR RANCE "On earth, however, this is a compara- DEPENDS ON YOUR tively simple ¡natter, for here we have rivers and lakes- in abundance which can RECEIVERS be tapped with ease. Not so on Mars. The only refraining water there is found around the poles; by sheer necessity, there- fore, the Aartians had to go to the poles for their water supply, and this is exactly what our telescopes reveal that they did. For the long, unswerving straight lines which we sec are part of the canals bring- ing the water down from the poles to the desert land there to irrigate it. So far the Lowell observatory has discovered almost 600 canals, but there are doubtless many more. They criss-cross the entire surface of the planet in every conceivable direction,

most of them, however, running due north . becomes simple wben your instructor is the Or^nirraph and south in the direction of the poles. Automatio Transmitter. Combined with a standard key and sounder or Wireless Burger, it will send you telegraph mes- Ì Not only do the canals cross the desert speed, which can be increased at will to match sageea aslow operator become pro- lands, but we see them carried bodily ficient. i Adopted by U.B. de n 4 styles, from across the dark blue areas which we know 32.50 up. all accurate. Circular free. to be irrigated vegetation tracts. The fact Omnigraph Mfg. Co., 39 L Cortlandt St, New York that the canals run across these areas is Holtzer -Cabot another proof that they are not oceans, as had been thought at one time. HIGH TONE ROTARY R R. P it Gives 600 ycle- "Now the lines which we see running whistling spark like Radio Receivers the et quenched gap. over the planet are really not canals Attains lull speed themselves, but are simply wide strips of in 1 second; atp. have honestly dead inside of 3 vegetation fertilized and kept alive by the seconds. earned their You do ant have water from the canals. The average width to wait for tills reputation of of the canals proper Dr. Lowell estimates Rotary to start nor do you have to to be about six miles. There are some of wait for it to etas. being the them, however, which are thought to be italwaya beats yea to it. much wider than this. The length of these The light revolving "Most Sensitive Receivers Made" discharger arm al- canals, however, is stupendous. There are lows a quick atart Other features are light weight, comfort- some canals which actually measure 3,400 and q ick stop. able shape, durability, perfect finish. Send 2,000 Will w k seta for Booklet 202 D for description. miles. A great many are over miles unto 1 Ìi. W. long. Dozens of them run for 1,000 miles, Used on 60 -cyd. Send 4a. for Bulletin B, contains current. and nearly all of the canals run in abso- many new pieces of apparatus HOLTZER -CABOT ELECTRIC CO. RADIO APPARATUS COMPANY OF AMERICA lutely straight lines. Parkway Building. Philadelphia, Pa. BOSTON, MASS. "The circular black points, mentioned above, which we see almost' invariably at I A NEW CHAMBERS COUPLER the juncture of one or more canals, are e No. PRICE ONLY foonr termed oases. They also represent vast LOOK 744, $6.00 Special Price tracts of vegetation and probably contain Positively un- large cities, farms and so forth. equaled for the money. Is "It must convince the strongest op- 6" high, 6" Receiving Set ponent of Dr. Lowell's theory, when view- `vide, and 14" ing Mars and its canals through a first - over all. Wou nd with class telescope, that these wonderfully E namele d

straight lines cannot by any possible chance wire, and has - $345 be the work of Nature. Its counterpart is a very unique slider. Wood- found nowhere on earth nor in the work mahog- heavens. And if by any chance, for argu any finished. Try one, you wilt not be disap- ment's sake, these lines should be of is pointed. many of them could not 5c. in stamps brings our 64 -page illustrated cata- natural origin, so logue, B.B -24. None otherwise. for any conceivable cause join and meet Street as they do and form these exact circulai F. B. Chambers & C areas. Their artificial origin is too ap hild; parent and cannot be otherwise considered With One 1000 OHM Receiver to -day. Dr. Lowell's theory has so far withstood the onslaughts of all opponents, This fine Receiving Set comprising three-slide Tuner, KNOW US Variable Loading Coil, Fixed Condenser, Silicon Detec- as a matter of fact, his explanation is to- tor and Head Set is self- contained and well adapted for either portable or stationary use. day accepted almost universally. You, too, should learn is of radical design. aking it possible to the move place point on any side of mineral. "But how do Martians the tre- of our large stocks of Loading Coil is enclosed within tuner cylinder and its mendous masses of water through their Electrical and Wire inductance is controlled by instrument switch on end of tuner. canals? For, as explained already, Mars lees Apparatus and in- tuner inductance controlled by sliders of improved lesr.n. is entirely level, and water does not flow telligent service. As THIS OFFER GOOD FOR on a level surface without a "head." More- agents for The Electro ONLY THIRTY DAYS over, during one season it must needs flow Importing Co. and J. H, from the north towards the equator, when Bunnell & Co. we as- We will send this complete receiving set with one snow cap melts 1.000 ohm re er bead band and cord on receipt of the northern polar under sure you of qual- 43.45 for 30 days only. This is an unus ual offer. the influence of the sun's heat. During the merchandise lend us your check today. if not entirely satisfactory ity money refunded if goods are returned within 10 days next season, however, this flow must be re- at lowest prices. versed for now the south polar snow cap St. melts, Ìa., 'iniversal Wire!ess Co., New Yorkk City with a resulting flow of the water Quaker Light & Supply Co., ph Pa. from the south to the north. "But how do the Martians succeed in OSTON WIRELESS moving the water? We don't know. Even Professor Lowell is silent on this point. Boston Receiving Transformer, 57.50 Terrestrial science simply has as yet not 1 Microfarad Condenser Variable Cond , Plates. 52.75 cast in metal 2 BBoston Detectors, advanced enough to offer an explanation.t box with binding posts. Insula- 51.00, 51.25, 5175, 52.25, 54.00 tion good for 800 volts A. to make a Agent for Electro Importing Co. and W. Bow- "Well, long story short. Flit Regular Price, 57.00 Special Price. $2 OO man Co., Manhattan and Adams Morgan Spark ternix and I decided to voyage to for cash with order eG Coils, Ever -ready Hash lights and batteries. Planet Catalog for stamp only. Mars. My little astronomical lecture was Rosenthal Laboratories, Camden, N.J. M. MUELLER, IS Devonshire Street. BOSTON. Mass. given solely for the purpose of refreshing 3'ou b,.ne;it by ntenticniag "The Electrical Experimenter" when writing to advertisers. www.americanradiohistory.com 299 October, 1915 THE.. ,ELECTRIÇA1.. , EXPERIMENTER future ! your mind as to Mars in order that Here It Is At Last reports which I shall make to ÿdù from the planet will be better understood by you This 1/6 K. W. Closed and your friends. Core Transformer "If our 'Interstellar' was able to suc- $685 ceed in reaching the moon without mishap, to Mars would After months of er- I felt sure that the trip peri mooting. and after not be an unduly difficult undertaking. making dosens of de- signe and model. we Flitternix was of the saute opinion. We have finally produced the intervening 50 million thoroughly pmatleal calculated that closed core wireless miles separating the moon from Mars trans rmer to retail at $8.85,! the price that should be negotiated by our space flyer formerly you had to pay for spark coil and batteries. 30 days, barring no accidents. While We have crificed nothing in quality or manufacture. within The sise is smaller -that's all. this may seem like a short time to cover This transformer will send message. f...au (20) miles, our speed of with a good aerial, instead of the 2 and 3 miles obtain. such an immense distance, able on spark coil.. Best silicon iron is used in its con. 1,600,000 miles a day, or 66,666 miles an struetion; the best enamel and cotton covered wire: mica eulation; sectionally built. hour, is only a trifle greater than the lt will throw a heavy. crackling spark that with prop - (65,533 miles an hour) ondenseers will fill a gap with a ball of fire almost speed of thc earth 1- 4 i n. in diameter. as it travels in its orbit around the suss.t send six (6) times as Tor ae in. Big Money This heavy epark will l spark soli. "We immediately made our preparations Send money order today for this new, marveloue little hours after I had emerged transformer. Shipping weight 10 lbs. and within six from the crater, the 'Interstellar' had left in Big Catalog of Newest Experimental the moon. And now for a little surprise! No Goods, 4 cents in stamps. doubt you noted that my voice does not Electricity Write today for our different kind of catalog. New sound the same as usual. You will have things in wireless and eleclricalgoods. New prices. observed, furthermore, that I did not stop The electrical industries offer won- I news talking since started. To break the for boys with THE ELECTRO -SET CO. Dept. E. gently to you, I am not talking at all! derful opportunities 1960 EAST 6th ST., CLEVELAND. O. While you are listening to my voice at a liking for electricity. The sala- this minute, I will be some 1,100,000 miles ries paid to trained men are large distant from the moon heading towards -promotion comes rapidly, and, BOY ELECTRICS Mars I best of all, the profession is not "The explanation? Simplicity as usual! overcrowded. Knapp Marvelectric "Before leaving in our 'Interstellar' we THE GREATEST stretched an immense aerial inside of the The opening of new lines, from canyon, the one of which I spoke to you to (such as -. several days ago. As you will remember, time time, wireless tel I told you then that it was open but a few egraphy and telephony), promise feet across its opening at the top. It thus attractive and paying fields to those formed a long, narrow slit at the top into who wish to specialize. The will which there was little likelihood of meteors to do and Special Training will dropping, which could destroy the aerial. We stretched four wires in all along the bring success to you, inside of the canyon, spacing thc strands six feet apart. Each strand is 6,000 feet The International Correspondence EVERY BOY SHOULD HAVE ONE long in order to give the required long Schools of Scranton can help to More fun, more Information than a hundred books. wave length in transmitting as well as re- make you an expert in 'electrical Finished as shown. Demonstrates Magnetism. Sole - noids, Resistance. Motors, Dynamos. ceiving impulses between Mars and the work. Hundreds of boys have Price $3.73 Moon, as well as between the latter and the already won success through Live dealers everywhere. Order direct, or ask your Earth. dealer to show you the Knapp Line and ineist on I. C. S. help. You can do the getting Knapp Goods. "To this aerial I connec:ed my latest in- Dealers not already handling the Knapp Line should same. Everything is made so clear ask for prices. vention, by Interplanetarian Radiotonsatic. Catalogue illustrating many epeoialtiea on request. It is nothing but an ingenious adaptation that you can learn in your spare KNAPP ELECTRIC & NOVELTY CO. of modern tele- mechanics and works as time, regardless of where you live 523 West 51st St. N. Y. CITY follows : or what you do. No books to "When the aerial receives a certain num- buy. ber of equally spaced dashes an ultra- sensi- BOY SCOUTS & JEWELERS tive detector is actuated upon which in Special Wireless Receiving Outfit turn operates a gas -valve relay. This relay There's big money in electricity. Get TUNES TO 3,500 METERS then closes its contacts, which sets in mo- after it by marking and mailing the Made For Long Distance Work tion the well-known telegraphone, invented attached coupon today. Finding out by Poulsen. A second ultra -sensitive de- costs you nothing. tector, also connected to the aerial, is in series with the registering electro- magnets Mark the Coupon -NOW of the telegraphone; in front of these mag- nets runs the moving steel wire, on which are then recorded the impulses coming in INTERNATIONAL CORRESPONDENCE SCHOOLS over the aerial. You will observe that no Box 1071 SCRANTON. PA. message can thus be recorded unless the B, IExplain, without obligation to me. how I can I original key dashes unlock the telegraphone qualify for the position before which I mark X. mechanism. At the end of the message the same number of equally spaced dashes tomobile Running Stenog. &Typewrit'g Embodies latest advances in radio engineering and will lock the Motor Boat Running Bookkeeping research. PRICE, 510.85. Complete catalog for 2c. stamp telegraphone mechanism. The Electrical Engin'er'g R. R. Accounting IRVING RADIO LABORATORY recorded message is now ready for re- Electric Lighting Good English tot Ev'yone 30 Irving Plate BROOKLYN, N. Y. transmission at any time desired. This, is Electric Railways Civil Service accomplished in Dynamo Running Architecture a simple manner too. ]AuTelep. & Teleg. Eng. Contracting & Build. I THE IMPORTANT SUBSCRIP- "I took our 300 -day clock and fastened Mechanical Eng'r'g Structural Engiu'g TION OFFER ON PACE 301 upon it a Mechanical Drafting Plumb'g & Heat'g SEE contact which would be closed Shop Practice Civil Engineering at exactly lI p.m. every night and would Steam Engineering Salesmanship TYPEWRITER PRICES SMASHED he opened again at 12 o'clock midnight. Mine Fore. & Supt. Advertising Yes have typewritertyeor prices light UChemistry Agriculture and left. and sell This contact closes a circuit in which is leaemaney than anyone else. lam the !largest rebuilt typewriter buyer in the United State.. I included the telegraphone mechanism. As Name 500 MACHINES AT SIO TO S15 Do not pays to ere per cent more whip yep rep soon as it starts the steel wire with its prices advanced Ir mená ßiÿ`. `but I séil to the 1 recorded message begins to reel off in front Street and No name pit of ehlnea G d For 3 Years of the two reproducing electro magnets, When you buy from me. you get a guarantee to 1 City State keep the een!ne in repair for 3 years. Write for which in turn are connected FREE deaeripttva cireuler. with a special tips! Cash" Carne. telephone receiver. Thus the telephone re- Dearborn Typewriter Each Drpt.. f f Camr.FM Present Occupation MI IN El MI IN IN In MIMI ceiver will begin to talk its message (if Yon benefit by ment'oning "The Electrical Experimenter" when writing to advertisers. www.americanradiohistory.com 300 THE ELECTRICAL EXPERIMENTER October, 1915

one was sent during that day) every eve- THE AURORA BOREALIS OR THE ning at 11 o'clock. NORTHERN LIGHTS. For Just "But connected to the telephone receiver (Continued front Page 245.) are several amplifiers, arranged in cascade. The last amplifier is attached to the mouth- It is possible to produce an artificial Such Jobs piece of the transmitter of my wireless Auroral effect in the laboratory, as Fig. telephone. Thus the weakest recorded talk 3 shows. Between the poles of a power- as This- on the telegraphone wire will cause the ful electro- magnet is placed an exhausted telephone of the last amplifier to talk into glass bulb. When a high -voltage electric the wireless transmitter louder than my- current is connected with such an ex- you can get the self. hausted globe in the manner shown and results you want "Now my 300 -day clock every night at also when the magnetic flux in the mag- is 11 o'clock also closes the contacts of a nets caused to pass through the bulb, only with an Ex- a remarkable change takes place, which tensionBit Hold- powerful relay, which in turn operates the generating plant of my wireless telephone, has considerable bearing on the apparent er. This tool is disconnecting it at midnight. Therefore action occurring in the Aurora Borealis collapsible -fits when the amplifier with its telephone be- as seen in nature. The artificial Auroras any And gins to talk into the transmitter of the produced in the exhausted bulb, as here kit. described, take a spiral form, the spirals that's only one wireless telephone, there will always be enough power to transmit it to you on tending to point toward the magnetic poles. pleasing feature Earth. This seems to confirm the theory that the streamers in na- of 'As soon as we arrive on Mars we will of the Aurora Borealis in probability find necessary ma- ture are composed of electrons, descending all all the to gaseous terials to erect a giant Radio telephone the outer envelope of the earth sometimes from a height as great as 300 plant, and if we succeed we will send daily miles. MILLER5 FALLS messages to the Moon, while my radioto- These spiral down, following the EXTENSION lines of magnetic force, toward the poles; matic relaying plant will transmit the mes- the spiral at the same time gradually clos- sages to you every night. I might also BIT HOLDER Nab ing up and decreasing in diameter as the Outer sleeve telescopes over Inner spindle mention that my ultra- sensitive detector field strength increases. The luminous globe and engages ut intervals of every 114". contains two radio -active substances, mak- Total length, extended, 24 "; collapsed, becomes brighter, due to this concentra- 18t". Chuck follows bits of " di- ing the detector such a marvelously sensi- tion and the improved conductivity which ameter and over Into bore. Is extremely tive instrument that it will work a set of strong -jawed and grips like n vise. results; a combined effect of the magnetic amplifiers in cascade when an electric and electric fields which are strongest at Will Help You Do Better Work pocket buzzer is operated one hundred and the poles, also helping to increase the con- Ask your dealer to show you this tool fifty tniles away from it, connected to the ductivity. In the proximity or neighbor- and also Millers Falls Bit Brace 772, using no Hand Drill 1980 and Acme Mitre Box. ground only and aerial! hood of the conducting layer the Auroral Send for catalog showing complete line. "You might say: Why use the relaying Moon streamers or rays come to an end, as the MILLERS FALLS CO., Millers Falls, Mass. plant on the at all? Why not trans- electrons or electrically charged particles Mars ?' New York Office: 28 Warren St. mit from to the Earth directly then return upon their paths and spiral up Visit our Exhibit "The reason is that when the weak im- again. in Block 28, Ave- pulses arrive from Mars, after having trav- nue D, Manufac- Regarding the state of the electrical turers' Building, eled from 50 to 60 million miles, they can- charge in the atmosphere surrounding the while at the Pan- not be sufficiently strong to pass through ama - Pacific Ex- earth at the periods when the Aurora position. the Earth's thick atmosphere. always Borealis occurs it was found by Andree, charged with electricity and 'static.' It is who made careful measurements with a BUILD YOUR OWN far better that the weak impulses should sensitive electrometer, that before the ap- operate the relaying plant first and send pearance of an Aurora, the positive elec- GRANDFATHER'S out from there very strong impulses which tric potential of the atmosphere diminished have but to travel some 238,000 miles to abruptly and in some cases it even became CLOCK Earth. "negative." WITH This also usually occurs when OUR HELP "We tested the plant thoroughly and it rains, but after a rain storm the positive We furnish blue prints. fin- after we had satisfied ourselves that it ishing material and inst ruc- charge in the atmosphere generally returns tions. Buy the works, dial, would work for at least 300 days I opened promptly. When the place, weights and pendulum from Aurora takes us at surprisingly low the telegraphone circuit and began to reg- the atmospheric potential takes up as be- prices. You make fine ister his message to you. It will be the profit building artistic fore and quite rapidly a high-positive elec- clocks for your friends last one which you will receive for 30 tro- static value. Thus we see that the Complete orks. 55 00. As it must needs take us Others with w chimes at all days or more. Aurora Borealis does affect directly the Prices. from five to 10 days to build a transmit- Ask for attractive free Mier. electrical equilibrium of our globe, and ting plant on Mars, you need not expect therefore it is perceived how it can affect Clock Company to hear from us for from 35 to 40 days. without any question the electrical tele- 1661 Ruffner St. You might, therefore, commence to 'listen graph lines and wireless systems built by PHILADELPHIA, PA. in' beginning with the 35th day from to- man, and which use, of course, in any case night. No message can ever be repeated, a power which is but an infinitesimal frac- for the 'wiping' electro- magnets of the tion of the vast amount of energy involved Hot Wire Ammeters telegraphone wipe out the magnetic im- in such effects as the Aurora Borealis. pulses from the steel wire as quickly as Bell Ringing Transformers they pass the transmitting magnets. Neither THE GRAVITATION NULLIFIER. Toy Transformers can you transmit a message to me, for no provisions were made to relay your mes- (Continued from page 251.) Sign Transformers sages to us when on Mars. Socket Transformes "I will now bid you adieu, my boy. ing together, drifting as aimlessly as thistle- for Night Light Think of us during the next 30 days! down and all shrieking in terror. Guns Good -bye-good -bye !" and wagons were overturned or wafted Vibrating Rectifiers There was a silence for some seconds, away by maddened, frantic teams. The Electrolytic Rectifiers and as I was still listening awestruck, 1 whole line as that gyroplane passed over it was suddenly startled by another voice went into such confusion as only a terrific Fire Alarm Switch breaking in : tornado could have caused. Boards Approved by Hallo there Allier, this is Professor .Cawthorn swept ahead, his orders be- the Dept. of Labor Flitternix. How's Yankton? Beastly old ing to block the railroad. As he passed town! Was once forced to sleep on a bil- over the yards at Caliente and put the liard table in the Palace Hotel, as all the nullifier into action switching engines lost rooms were full. The robbers charged me their traction and either spun their driving "Construction of the $2.50 for the "room" plus the regulation wheels uselessly or wobbled off the tracks, rate of 50 cents an hour for the use of the piling great loaded cars against each other Audion Amplifier" billiard table! Mean town, that Yankton! like bales of cotton -batten. G.N.2 was less with working drawings, particularly de- Well, good -bye than half a minute gliding back and forth scribing the transformer. Price, 50 cts. There was a snapping noise and the over that yard, and it took the enemy four rhythmic low sizzling sound stopped days to restore working conditions. 17 Board THE MISCELLANY KANSAS CITY, rMO. abruptly. All was quiet once more. On again, down the line, stalling the first (To be continued.) train but allowing the hundreds of tons You benefit by mentioning "The Electrical Experimenter" when writing to advertisers. www.americanradiohistory.com October, 1915 THE ELECTRICAL EXPERIMENTER weight of the following train to crash into the first. On again, through the Vegas Binder Canyon, where a half -gale of wind dis- Handy tributed feather -weight moguls and freight cars up along the jagged, precipitous rocky for THE ELECTRICAL EXPERIMENTER sides of the mountains. Another train of Holds and preserves 13 issues, each of which can be 17 coaches loaded with troops fluttered inserted or removed at will, without tools. Will keep away -all coupled -across the St. Piedras HE your magazines perfectly for all time or just preserve divide, where it straddled the summit, lying T them like new till you bind them permanently. Made of on its side. But, except for some wrenches heavy material, extra strongly reinforced and sprains, not a man was hurt, for there 'I ELECTRICAL at the back and covered with handsome C was not an ounce of weight in the entire green cloth, suitably lettered in gold outfit, men or cars. EXPERIMENTER Shipping weight 2 lbs. Add sufficient postage, other- On again, across the wild, arid Tepe- wise we will have to send binder by express. guaras plains, where they sent 3,000 of Cabellero's Mexican warriors and horses Order a BinderTo -day and Preserve Your Magazines. fluttering in the air like dead leaves. and Experimenter Pub. Co., Inc., 233 Fulton St., N. Y. howling to every saint in the calendar - and many who are not there -to save '1 Book Dep't. them. On again, over the Allies' head- quarters, where the Jap general, Kioki, and his Chinese ally, Lu Kien, were wafted A BOUND VOLUME ELECTR CAL EXPERIMENTER FOR 75e. Bound from a In aubstantiat green cloth; lettered in gold. Poetate on 3 Ike. le extra. Book Department. A council of war, clinging tenaciously REAL BARGAIN. EXPERIMENTER PUBLISHING COMPANY, Inc.. 233 Fulton Street, New York. to their camp seats, the Jap settling with sadly ruffled dignity on the flat roof of a 'dobe ranch house, the Chinese drifting against the gyroplane, which had circled down to 400 feet, and where welcoming If You Are Willing To Pay hands stowed him in the frame -a prisoner for General Illington. A FAIR PRICE FOR THE BFST_IN ITS LINE In advance of the G.N.2 flew two aero- "MARSBRIGHT" BUY planes, from which were dropped the at- ".fate. tractor pellets whenever they came in ad- vance of a train or passed an occupied MARS -BRIGHT siding. Then, as Cawthorne followed, his THH BE GUARANTEED BEST i nullifier threw those trains into most ap- THE FLASHLIGHT BATTERIES palling confusion. At Mirau Nuevas the BATTERY MADE OUR PRICE IS FAIR- OUR BATTERY THE BEST operation of this influence, helped by a BRIGHT STAR BATTERY CO. strong breeze, lifted and deposited an NEW YORK. N.Y. enormous ore bin and the terminal ma- BRIGHT STAR BATTERY CO., New York MONTREAL chinery of a great aerial cableway along the main line tracks. In four hours the G.N.2 had blocked 300 miles of railroad at over 40 points. They turned back, following a direct air line over the mountains to Illington's head- BOOK quarters. Cawthorne reported amid deep ACCEPT THIS FREE and fervid congratulations, and then laid IT'S off for a rest. For nearly 60 hours his INVALUABLE YE head had not touched a pillow. CAN'T BE BOUGHT Six . hours later-it seemed but six minutes to him -Capt. Berger came to the Will you take lesson tent and aroused him, with the news that a 20 Wireless Course ab- the general had received an important dis- solutely FREE -even postage charge prepaid ? patch from Washington and wished to see Just as you A course that tells you everything you can possibly him. will receive it, want to know about "Wireless " starting off in Lesion No. 1 by explaining the Principles of Electricity. The Second "Captain!" exclaimed the general as cloth bound, and Third Lessons are devoted to magnetism. motors: Cawthorn half staggered into the room, "I generators and wiring. And then. by simple easy stage. size 7 x 10% this wonderful Course takes you into "Wireless." The felt it necessary to inform you of this at ins., 160 pages, mysteries of "Wireleoe" are unfolded to you by the use of once." yueb simple language so ekilRully used, that of necessity He held out a dispatch: 20 lessons, 350 ou must understand every word. The subject is not "To Brig. Gen. N. C. in tables, treated superheislly, however, for there le a whole lesson Illington, com- illus., 30 devoted to the Theory and Mathematics of this epoch mand of the Fifth Division at Montoya: with every bit of marking subject. To lend charm to the Course, the last "Your Lesson (No. 20) Is devoted to history of Wireless and the report on the work of the Caw - information on men who developed it. The wireless course positively thorne nullifiers received. Hearty con- Wireless you can fcannot be bought, but will he sent absolutely free with a ull year's subscription (12 numbers) of the Electrical gratulations. It is advisable that immedi- possibly want, be- Experimenter at 51.00. It's the biggest dollar's worth ate action be taken you can ever any it against the enemy's sides valuable in- to-day enclosing $1.00. Send new before you forget. transports and battleships now in the Gulf formation on Elec- The coupon below is s convenient way. But de It of Mexico. You will detail Capt. Caw - tricity, Magnetism "n. thorne and his party, with ample escort, and Theory of them THE EXPERIMENTER PUB. CO., Inc. to proceed to the Gulf and report to Ad- -and it's FREE as Publisher miral Young for operation against those explained. "The Electrical Eaperl,nnt.r Mafa,lns." ships. "By order of the President. "JOHN J. SMITH, Secretary of War." Cawthorne stared blankly and muttered: EXPERIMENTER PUB. CO., 233 Fulton St., New York "Impossible, general! The nullifier can Gentlemen: operate only on land. We have not dis- On your absolute covered why, but guarantee that your 20 Lesson Wireless Course is just as we know that water is described by you, you may a perfect insulator against send me same FREE. You are to send me this Course the electric at once, all charges paid, enter zone which counteracts the gravitation. and my name for a full year's subscription to the Electrical Experimenter, 12 numbers, The attempt would be useless! The Navy for which I enclose *$1.00, the price of the Electrical Experimenter alone. will have to be depended on to clean out the Gulf- unless-" (If a 2 -year subscription is desired, enclose $2.00.) "Unless what, captain ?" My name is "Unless I can at once go North to my experimental shops. Did you ever hear My address is of the Poniatowski Arc, sir ?" -"Neverl"...... _ _. _ _ *Canada and Foreign Countries, $1.25-2 years, $2.50. Cawthorne smiled grimly. "I think that You benefit by mentioning "The Electrical Experimenter" when writing to advertisers.

www.americanradiohistory.com 302 THE ELECTRICAL EXPERIMENTER October, 1915

I will send my 25c Book For not one man In a thousand has, although it was discovered several years ago, but sus- Strong Arms MEN, pected only of capabilities for long- distance "PORCELAIN for 10c in st'nips or coin signaling. "But" -his voice sank into, very "THAT'S OUR BUSINESS" low, earnest tones know that with the Illustrated with twenty full - WOMEN -"I half -tone cuts showing apparatus we have completed in our shops Standard and Special Shapes, Regardless exercises that will quickly and develop, beautify and gain you on land or an admiral at sea would of How Difficult tterms an your have as full control over the firing of the shoulders,it arms á ñ an, We illustrate one hard shape we make. without any apparatus. CHILDREN enemy's guns as the enemy himself has!" A pair of rolls 7h" long and 1y4" in PROF. ANTHONY BARKER The general dropped back in his chair. diameter with 8 holes on ends and middle. 560 "What! Another ghastly invention ?" They must be perfectly straight and we Barker Bldg., 110 W. 42nd St., New York make them so. It's hard but not for us. "Exactly! If I can have leave of ab- We can make your difficult designs also. sence for ten days -perhaps a little longer, Send us blue print for quotations. America Must and take Kilroth with me, I think that I BUILD Rely on Her BOYS can you the power to not only coun- Union Electrical Porcelain Works Formerly first, we a now last inn bring aviation. You boys must make termand every order of the enemy's com- I first again. Study aeronautics, build TRENTON, N. J. I a model man -carrying machine. manders, but to issue the orders yourself - We will send you plane. with the certainty that they will be obeyed. /OIIIJ,t\e-, Nieuporl Monoplane 25e. Wripla B OV Best Boys Maaazlne In the world allhe pries ,, Biplane 25e. Curless Hydroplane The gyroplanes and nullifiers will be here 1 JS I DO YOU LIKE RATTLING GOOD STORIES t 35e. Bleriol Monoplane 15e. Cur- Are you interested in baseball and Whim ties Flying Boot 25e. Cecil to use if needed again, and Capt. Berger -- - 3FLta1RTI53 Peali Racer 25e. tics, electricity ,mechaoics,photography, memoem Complete Set of Sis - $1.25 postpaid. -is fully capable of handling them." f1/1467161101 carpentry, stamps and coin collecting, 48 pase Catalog of "Ideal" Mode The general grunted hoarsely: "I've got amateurjoorualism,gardening and pets? BOATaGCowpfeteA,eoplanea one J'aapdet, se. If you are sit down right now and send a to believe you, Cawthorne! I've got to! quarter y lI: EAL AEROPLANE & SUPPLY CO.. 76.62 W. Broadway. N. Y. once !" Companion' a large 32 page Illustratedlutst ated hoy e Your passports shall be made out at monthly magazine. It is chock -fall of the (The End.) very beet boys' stories. clean and whole- some, full of life and action, and bas reg. MORE MONEY FOR YOU alar departments every month on all the Increase your income riting show above subjects besides special articles of cards. Big opportunity for ambitious A POWERFUL ELECTRO MAGNET qIf will men and women. Experience unnec- FOR BATTERIES. send 85 cents atonce for a essary. Our practical coulee teaches year su ubecription we will mail you a you quickly and captains the remarka- (Continued from page 272.) copy o(Connle Mack's new Booklet, ble results obtained with Litholia "The Secret el Success In II" FREE Colors. Whatever your position. One year 25 cents, R I year 15 Bents, Three months for 10 rents. write for FREE BOOKLET now. Boys Companion, 1114 Mouth La Salle street, Chicago, III. Don't bother about. the money. It N. and S. poles. When the current passes you are ambitious and want to become around the coil in a clockwise direction expert show LTHOIAIL.10 COLOR (i.e., right- hand), the magnetic póle pro- raiNY PROFITotsti C O., 02 Flatiron Bldg.. New York. duced is a South one in a direction toward by reading the reader. Every magnet has two poles of opposite polarity, no matter how small THE it may be. Unlike magnetic poles attract each other and, conjointly, like poles repel I ELECTRICAL each other, as indicated at Fig. 3 B, where the S. pole of a magnet is attracting the EXPERIMENTER N. pole of the magnetized steel compass Why needle. The end of the compass needle not help your that points toward the north magnetic pole friend by giving him of the earth is. strictly speaking, the "north this magazine when seeking pole,' or the actual "south" pole f of the magnetic needle, as only unlike poles Iyou have finished 1:400;+ Throw Away attract each other. reading it? WITH THE "AD MAN." YOUR FRIEND WILL THANK ')/1 r Worn `Tires Along You about the time when as a boy I YOU HEARTILY can get 5,000 miles more first became a reader of magazines I can service from them. remember how people looked upon the ads. ilowoonoommommoonommlit For over three years European Motorists bave found in them. My dad used to tear the been getting front '10.000 to 15.000 miles ont of advertising pages out and their tires by "half occasionally use September,Morn -soling" them with Steel `hem for shaving paper, WATCH FOB. Exactly like Illustration. Studded Treads, Just as WO half -sole our shoes but most times The latest fob out. Has bewitching little when the first sole gets thin. the stove would get them. Those days figureof Mlss"September Morn" handsome- In the past S months over 5),0110 American when mother saw a ly embossed on heavy metal plate. Beautiful Motorists have followed their example and are department store "ad." oxidized silver finish. Size of medal sy. x saving $50.00 to $200.00 a 3-ear in expense. she always.' remarked, 'Well they say it's IX. Genuine blackleatber strap. Boys. a tire real work of art. Classy, alluring. Bakes Guaranteed 5,000 Miles without Puncture worth $2.50, but I'll bet it isn't worth even all take notice. Agents wanted every. as much as they ask, and knows the where. Dandy sample fob and our great Absolute freedom from tire worry-blowouts, Lord easy money proposition to hustlers seat punctures. riincuts and rutwear eliminated -no price is low enough." Those were the Postpaid 25 cents. matter whether your tires are old or new you views, and the result was that advertising NOVEL JEWELRY CO. should put on Durable Treads at once-they 707 Lewis Block Buffalo, N.Y. cover your tires from rim to rim- nothing can didn't pay as well as to -day, for the con- work In between -that's why we guarantee them fidence of people was lacking, due, of $1 PER MAN PER COUNTY as we do, course, to the belief held by many adver- Strange invention startles the WE SHIP ON APPROVAL -prepay the express world-agents000 amazed. Ten inexperienced men and allow you to he the judge. Durable tisers that people wouldn't believe all they divide $40.000. Korstad, a farmer, did $2.W0in Treads 12 are cagily applied In your own garage in 30 said. on paper anyhow, so they had better 14 days. Schleicher. a minister, $195 hat minutes without extra tools. hours. 51.200 cold cash made, paid, banked exaggerate a bit. Well, they did exaggerate by Stoneman in 30 days; $15,1100 to date. A SPECIAL DISCOUNT to motorists in new terri- hot or cold musing water bath equipment tory on first shipment direct form the factory. all right, but most of them forgot when to for any home at only $6.50. Selt- heating. Mail the coupon today and we'll send full No plumbing or water -works required. In- you qu't. Exclusive sale. Credit given. Send information, - sample, and copy of signed guar- vestigate. antee without any obligation to you. It's different to -day. When Ma sees an DO money. Write letter or postal today. ad. now in a good magazine and it looks as ALLEN MFG. CO., 4170 Allen Bldg., Toledo, O. COLORADO TIRE & LEATHER CO. though a real bargain is advertised, she 109 Tread Bldg., Denver, Colo, off And Draw for Dept. 19. Box 228, Chicago, Ill. sends right for it, because she realizes Magazines. 910 Woolworth Bldg, New York. that no good magazine would think of Newspapers, carrying the advertisement of a non -re- etc. This Today - - -- Earn Dig j liable concern. Therefore when you see Money Colorado Tire & Leather Co., an in 109 Tread Bldg.. Denver, Colo. advertisement The Electrical Ex- All Branches of Art Tough BY MAIL or Loosl Dept. 19, Box 225. Chicago, perimenter you need have no compunction Classes. Write for illustrated booklet, terms and list of Ill. successful pupila. 910 Woolworth Bldg.. New York. about sending an advertiser your money, Associated Art Studios. 2110 Flatiron Bldg., N. Y. Gentlemen: for the publishers of The Electrical Ex- Please send me. without any obligation, full in- perimenter absolutely and unquestionably Show Card Writers Earn $80.00 to $200 formation, sample and copy of signed guarantee for 5,000 miles. guarantee the integrity of every advertiser a Month -LEARN FREE Name in his dealings with their subscribers. we will furnish a thorough course Read this last paragraph twice in Show Card Writing and Lettering Address -it's absolutely free to introduce our worth while, and above all, it means that colors, if you will purchase an assort ant of Alpha Colors to use while you, can absolutely rely on the advertise - practicing. Particulars for stamp. I My Tire Sizes are ment of every advertiser in The Electrical ALPHA COLOR COMPANY, Inc. Experimenter. MILTON HYMES. Dept. T, 81 E. 125th St., New York You benefit by mentioning "The Electrical Experimenter" when writing to advertisers. www.americanradiohistory.com -w Scientific Exchange Columns UNDOUBTEDLY you have at the present time some things for which you have no further use. Do you wish to sell these things or exchange them for something. for which you have immediate use? There is no surer 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 30.000 interested people will see your ad. It is further- more the cheapest advertising medium for you in the country. Dealers' advertising accepted in Opportunity Exchange Columns only. The rates are: One cent per word (name and address to be counted) minimum space 3 lines. Count about 7 words to the line. Remittance must accompany all orders. We reserve to ourselves the right to refuse any advertisement which we consider misleading or objectionable. Advertisements for the November issue should reach us not later than October 5th. The Classified Columns of "The Electrical Experimenter" Bring Positive Results.

TO SELL - One telescope, 3 feet long, special FOR SALE - $15.00 Murdock loose coupler, pri- READERS-1 want the following magazines: lens, good condition. Premo camera, pictures 254x mary rewound with 140 turns and tapped to two Popular Electric,., 115)8, from beginning to Septem- 3 In.; guaranteed; cost $1.50. Both for $1.55 pre- tau -polut switches on hard rubber plate. Worth ber, 1909; January !Udders Nat. Electrician, 10,x0: paid. Richard Gaillard, 1719 Pendleton St., Colum- $20; will sell for $10. Murdock tuning coil rewound June Eloc. & Meche,, 1908; January, 1909; April, bia, S. C. as 2,000 meter loader with nine -point switch, slid- 1911; October, 1912; August Elec. Experimenter; ers removed; $2.50; $18 case of Dietagen drafting 1913, January to April; 1914, January and April. I WILL TRADE a complete wireless set, con- Instruments; good as mew; $7.50. Edwin L. Powell, For these will give 40 Elec. Mag., 2,000 -ohm head- sisting of the following articles for an Indian or 1206 E. Capitol, Washington, D. C. set, or cash. Harold E. Hickey, 1435 IIoward St., Harley Davison motorcycle of late model and in Philadelphia, t'a. good condition: Loading coil, receiving transform- EXCHANGE -Du complete wireless receiving out- er, 3 detectors, potentiometer fixed condenser, 2 va- fit. Want canoe or gasoline engine; prefer motor- NAVY Type Loose Coupler; new; $s. Also com- riable condensers, spark colt, gap key, magneto, cycle engine, or what have you? All letters an- plete portable set. What have you to exchange? Holtzer -Cabot receivers, telegraph key and sounder swered. Randall O'Brien, Louisiana, Mo. Hathaway, 856 Fulton St., Brooklyn, N. Y. Ewing, and a 32 -cal. revolver. Address Ilerbert outfit instru- Point Marion, Pa. Box No. 62. FOR SALE - Brand new wireless FOR SALE OR EXCHANGE-Westinghouse step- ments; never used. For particulars, write L. J. down transformer, type A, 10 -volt amperes, 60 to HAVE complete wireless set, racing bicycle, mis- Becker, P. O. Box 339, Galveston, Tex. 133 cycles; In Al condition. Will exchange for cellaneous electrical good., two revolvers. Waut Type O Crystaloi, or 2 -inch coil. W. Beattie, 51754 motorcycle, or make offer. Will also sell separate- WANTED-E. I. Co.'s 54 11.W. transformer coil Cliestlnut St., Lebanon, Pa. ly. All correspondence answered. Maurice Gelb, No. 8060. Must be in good condition. Write. Lloyd 74 East 116th St., New York City. Copp, Center, Ind. FOit SALE -Two good electric motors in first- class e 1 -12 horsepower, $5; 1 FOR SALE -Wireless outfit. Has single slide tun- HAVE $9 worth of American model builder. Would litio.; -6 horsepower, like good loose coupler, or what have you? William $S; MOO feet of goal comedy moving picture film, er, electrolytic detector, peroxide detector, con- $4. David. denser, two -point detector switch, potentiometer. Collins, Gran Ville, Mich. ll. 711 S. Kedzic Ave., Chicago, Ill. Mounted and connected. Price, $6, or will sell Mass. FOR SALE -X -Ray tube in good condition; die., I WILL EXCHANGE a high -grade cornet for a parts separately. Box 84, Newbaport, 4 inches; will sell for $2.75 prepaid; also step -down half or quarter N.W. wireless transformer. Have WILL EXCHANGE -$5 Seneca plate camera for transformer, $3 prepaid. Write C. A. Barley, 708 a lot of copper ribbon for sending transformers. spark coil or dynamo. Write to Elmer Dries, 205 S. Dolphin St., Baltimore, Did, WIIl sell it out at 3 cents per foot. Henry Graves, Jr., Geneva, N. Y. Market St., Shamokin, Pa. FOR SALE-Name plates, battery, shunt, phones, OLD jump spark coil, telephone generator and re- aerial, ground, on, off; 2c. a piece. Henry G. Asch- SALE OR EXCHANGE -One Weeden toy motor; ceiver, home -made tuning coil, . Popular Mechanics brenner, 7617 Carpenter St., Chicago, Ill. 1 -20 ohm sounder; 2 -50 ohm relays; 1 small Leyden 1913, lithograph locomotive model. Will sell or WOULD Ilke to purchase, second -hand, a Ritchie jar; 1 D.P,S.T. switch; 1 voltmeter; 1 telephone exchange for wireless goods. Ralph L. Kunau, Sa transmitter. Alexander V. Bollerer, 77 Linwood bula, Iowa. induction coil; 4 in. or 5 in. spark; good condition. Apt. 9, 2103 N St., N. W., Washington, D. C. St., New Britain, Conn. FOR SALE Oft EXCHANGE -New electric mi- $7 FOR SALE -1,200 meter, loose coupler, $2.25; hooks on croscope, projector; guaranteed; 3s -inch coil, wire- '/- WILL SWAP electrical chemistry and less key, loading coil with switches; $3 Murdock inch coil, $1.50; fixed condenser, 25e.; plate con- physics for anything useful. Henry Priebe, Kent, variable, spark gaps, powerful battery motor, ex- denser, 35e.; upright detector, 60e.; Simplex ty1'e- Ohio. -cellent portable receiving set, stamp collection 1,000 writer, 60e. C. Stanley, 405 Jersey St., Buffalo, rare varieties. Want Brandes Transatlantic phones N. Y. WANTED - One -Inch spark coil and gap; good condition. Have electric engine and car, 80 feet and wireless apparatus. Write D. Goodman, 118 FIRST REMITTANCE of $1 gets a coherer and Seventh Ave., McKeesport, Pa. track; one railway switch: same as new: value, $9. decoberer complete; never used; postpaid. Instru- L. D. Smith, 28 Newark, N. J, new. D. Pointer St., WILL EXCHANGE -A 1 -K.W. closed -core, bigb ment worth $2 when Wm. Wagner, 123 W. voltage transformer and casb for a Type "D" re- 4tb St., Duluth, Minn. . EXCHANGE -A Gem adding machine in good ceiving transformer, De Luxe or Blitzen tuner. All WILL EXCHANGE-A 6 -volt, SO -ampere Williard working condition; cost $10. Want a pair Brandes correspondence or propositions answered immediate - storage battery for polarised relay or phonograph, Transatlantic phones or a good 110-volt Universal ly. John B. Hawley, Jr., 912 College Ave., Fort or what have you? Samuel Cohen, 1938 Pitkln motor speed range from 3,000 to 8,000 r.p.m. with Worth, Tea. Ave., Brooklyn, N. Y. load. O. W. Nelson, 4333 Elm St., Calumet, Mich. WILL SELL -3,000 -meter mahogany, factory - FOR SALE electric first FOR SALE -Two one -inch coils, $2.50 each; two made loose coupler, new type S Dynamo -Motor -A Baker coupe in -class small motors, 50e. each; quarter-inch coil, 75e. cheap; Gravity cells, variable condenser printing condition with new batteries; three passenger. On Moershfelder, 34 Ketchum Pl., Buffalo, N. Y. press motors; can use spark coil Write anyway. account of Illness of owner, will sell at bargain Carl Barnckol, 2317 Milwaukee- Ave.i Chicago, Ill. price of $500; cost new, $3,200. S. Gerushack, 817 Excelsior motor cycle en- West End Ave., New York City. FOR SALE -Four H.P. gine With earb., 4 H.P. 2 cycle, 3 port en- FOR SALE 011 EXCHANGE E. I. wireless $15; -$45 gine; use as stationary, marine or portahle, with goods, shotgun, 8 -volt dynamo, 400 exposure kodak, WANTED -One Bulldog 1 inch or.1' -Incb Spark Coil. i. Wiley, 1214 E. Madison St., Portland, Ore. carh. coil -less oil cups; used very little; $25; one Oliver typewriter, Electric vacuum cleaner, 8-ineb of fan, Moving picture camera and outfit. Verner FOR SALE -Resonator, 75e.; Potentiometer, set cycle car wheels, axles, tires and tubes, set Hicks, Marion, Ill. 75e.; Helix, 75e.; Variable Fixed Condenser, 75e.; steel castings for four cantilever Krupp springs, Fixed Condenser, 25e.; Galena Detector, 50e, $60. For further description, E. W. Jenny, 3821 W. FOR SALE -$17 takes Blitzen receiving set in Leighton Gilbert, Bristol, N. Y. 34th St., Cleveland, Ohio. perfect condition, without phones. If interested FOR SALE complete wireless sending and FOR SALE -Complete Wireless Outfit_ Consists write Chester Fuss, Little Valley, N. Y. . -A receiving outfit. Cnst me.$40. Will send for $20. of double slide tuner, condenser, potentiometer, FOR SALE -Fleming valve detector, new, $3, For complete list. of .instruments send to following detector, buzzer, 1,000 -obm receiver, 154 -inch coil, coat $6; 1 -inch Bulldog coil, with extra large address: Horace-Hinz, 327 Old Bergen Road, Jer- fluted zinc gaps. helix, condenser and key. All platinum points, $2.50; No. 9260 Sending condenser, sey City, N. J. mounted on suitable base. No home -made instru- ohms, set, consists of $1.50; Polarized relay, 50 $2.50. Every- FOR TRADE OR SALE -Good D. C. Fan, fourth ments. $6. Portahle receiving thing good as new. Max Kuhne, 94 River St., K. W. Transformer, fine Alto Saxophone, Revolver, loose coupler. galena detector, condenser; all in Hoboken, N. J. etc. Will trade some of these for a good Micro- good case, $2.50. Motors, telephones, cameras, aerial and magnet wire. Write for particulars or FOR SALE- y -incb Spark Coil, $1.35, postpaid; scope. Also want Camera, Storage Battery Motor, X -Ray Outfit, etc: Send your and make send money. Everything guaranteed. Paul Wood- Spaniding single end punching hag cover. 50e. ;; list ward, Rodney. Iowa. both good condition, Paul. S. Potter, Riceville, offers. L. Smith, Oak St., Ashland, Ore. Iowa. BARGAIN -Daily Life of a Railway Mail Clerk, WANTED -2,000 -ohm headset, or one good loose . coupler. Have relay marked 2111 ohms and sounder WILL Modern Business Penmanship, New Commercial EXCHANGE -New three slider Tuning Arithmetic, Civil Service Manuals 1. 2 and 3. marked 2n ,,lems, Will trade for any of the shove, CoI1, 8 a 12 inches, tested for Arlington, for serv- $3 takes entire lot. Mark Kistler, Centreport, Pa. or will sell cheap. Wilber E. Dittemnre, Redmond, Icea any live boy can render. For Sale, slightly Ore. used 54- kilowatt "Blitzen" transformer. Lloyd FOR SALE -1 De Forest Audion Detector (with dress, Pitman. N. J. new hnlh and batteries), $15; an E. I. Co. 5,000 - SALE OR EXCHANGE -Complete wireless set, meter loading coil, $1.50: Fixed variable condenser, consisting of 1 -inch coil, helix, gap, condenser. WHAT have you to trade? Join my Bureau of $1: oscillation transformer. $5: a pair of 3.000 - key, aerial switch, double slide tuner, galena de- Trades. Have over 500 members; trades arranged ohm "Government" phones, $5; Variable condenser, tector, receiving condenser. single headset, Brandes anywhere. Send for full particulars. 3820 Lee $2; a Bunnell Mascot Rotary variable condenser, 1,000 -ohm receivers, binding posts. Will either Ave., St. Louis, Mo. $8; a 5.000 -meter navy type loose Coupler. $5. sell or exchange for .Ludion or Variable condensera. These instruments are in first -class condition. TYPEWRITER -Cost $100. Good as new. Will Jeter. Pinkston, Valdosta, Gu. exchange Other apparatus on application. If Interested for $18 Camera, Electrical goods, Books, write George D. Todd, Jr., New Albany, Ind. EXCHANGE- Murdock Tuner, variable, cash for Mall -order Goods, Musical Instruments, Athletic K. W. condenser; also other apparatus to ex- goods, Bicycle, Automobile Accessories; $18 Cash, HAVE one 110 -volt D. C. Fan Motor. one A. C. change for good transformer. Give description to or Offer. What have you? Write. Particulars 110 -volt, 125 -cycle "Emerson" Fan Motor, oue Vol- Arthur Sackn, 2670 E. 40th St., Cleveland, Ohio. FREE. H. Victor Itmg, Box 3461, Boston, Mass, ume of "Practical Electricity and Engineering" and four volumes "Electrical Review and Western FOR SALE -Large Electro tuner, $1.75; variom- FOR SALE-Clapp Eastham Ferron Detector, $5; Electrician" and sane cash.. Will exchange for eter, 50e.; 11 -plate variable condenser. 75e.; 9 -volt Manhattan tubular condenser, $3.50; Brownie No. any first -class wireless apparatus; want phones and rotary gap (8 electrodes). $222.50. All instruments 2 Camera, $2; or what am I offered? -Win. Mat- Andine Detector. What have yon? John Kidd, in excellent condition. Stuart W. Pierson, Car- thews, care Walbridge & Co.. Buffalo, N. Y. 121 Leslie Ave., Niles, Ohio. - rollton, Ill.

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"HYTONE " -j¡ K. W. set for sale; condition FOR SALE OR EXCHANGE- Stevens' "Favour- FOR SALE OR EXCHANGE-One Spark Gap excellent, price very reasonable. This apparatus, ite" 22 cal. ride, value $3; will trade for Crystaloi mounted on marble base, 50e.; ene Cat Whisker operating station 111A, now 1ZW, has covered re- or Radioson Detectors. Gartz Windenburgh, La- Detector mounted on slate base, 80e. R. A. Clapp, markable distances. Record, 850 miles. Come and mont, Iowa. Groton, N. Y. inspect apparatus personally if possible; if not write for photo and description without delay. EXCHANGE -Brase upright Microscope, $1.75; FOR SALE OR EXCHANGE -One motor and Have just installed more powerful set. Wm. H. Kodak, Prelim Jr. No. 1, 2y x 354, $1.80. Want bicycle. Write for particulars. Lloyd W. Cam- Allison, Worcester, Mass. Loose Coupler, not home-made. Porter Bennett, eron, West Collingswood, N. J. Mesquite, Tex. A COMBINATION 4 x 5 nr 5 x 8 Plate Camera FOR SALE OR EXCHANGE- Sending and Re- (Tripod, one French and one Morrison Wide Angie FOR SALE-54-H. P., 110 -volt A. C. motor, ceiving set. All in good condition. Write for Lens (each cost $25), Plate Holders, carrying $27.50. Will buy or trade 2 -inch coll. C. P. Kel- information. Auythony G, Jurincic, 9350 Commer- cases, etc.; a bargain. W. E. Day, Pittsfield, ley, Irving, Ill, cial Ave., Chicago, Ill. Mass. , FOR SALE-4 s 5 print washer, used once; two FOR SALE-3A Brownie Camera (post card 1 HAVE 3 transmitters, 2 ringing trees, 2 tele- 8 z 10 trays, dark room lamp, Drake's Multiple size). It is brand new; has never been used. phone receivers, 1 desk telephone, 1 Edison Pri- Picture attachment, size 4 z 5; acetylene bicycle Price $9, if taken at once. E. Haugerud, Scap- mary battery, 1 telephone generator worth $25. lamp; Year 1913 Scientific American, Spauldin$'s poose, Ore. Will swap for wireless set or apparatus. It. C. Note, Speller. Write for description and prices. Bayley, 10 Main St., Plymouth, N. H. Donald L. Zook, Denver, Ind. FOR SALE OR EXCHANGE -Chemical labora- tory outfit. nearly 300 pieces; will sell whole or FOR SALE-Set Ives Electric Train, 3 pieces; FOR SALE -First -class wireless set at mod- in part. 8 Vol. Cyclopedia, I. C. S. Text -books of 8 Curve, 10 Straight, Third Rail Track, practi- erate price. Write for particulars. Gogerty, 210 Chemistry and Electrical Engineering. Also other cally new, worth $0, will sell for $3.50. H. Reid Ave., Brooklyn, N. Y. books and articles. Sell cheap for cash. Will Ananiantz, 700 West Washington, Los Angeles, exchange for suitable articles of equal value. Cal. FIRST MONEY ORDER for $10 takes either pony Complete lists exchanged. M. Wand, 118 Crane WANTED -A 2,000-ohm double headset, each re- 16-V. dynamo or % -H. P., 110 -V. D. C. Motor or St., Schenectady, N. Y. ceiver 2,000 ohms. R. B. Watt, Box 1, Staple- 1 -H. P. Gas Engine. Maurice Lane, Genesee, Ill. ton, N. Y. WANTED -Receiving and sending instruments. FOR SALE-One Electro Loading Coil, $1.75; Transformers from 1 -6 K .W. to 1 K. W., Vari- FOR SALE OR EXCHANGE -Rotary Spark gap one Electro Loose Coupler, $2.25; one No. 2 able condensers, etc. Have one set of sis books to work on dry batteries, Geissler tube, Harper's Brownie Camera, $1.60; all for $5. Merwin Finkel- of the Practical Reference Library (fine), Auto- Aircraft Book. Spark gun, set of Meccano No. 3. stein, 308 Eddy St., Ithaca, N. Y. mobile course, rifle, relay, omnigraph, story books, Carl Seternfeld, 305 Lexington Ave., New York. FOR EXCHANGE -Eastman folding kodak, Med- camera, revolver, home -made voltmeter, ammeter, FOR SALE-Omnigraph Dunduplex transmitter, ical Coll, Stepdown Type "N" transformer, cost galvanometer, Wheatstone Bridge and old maga- sounders, relays, keys, aerial Insulators, small $4; Electro and Delta electric bicycle lamps, Bopk zines. Walter Franseen, Woodhull, Ill. motor, tape transmitter and wireless goods. Write cost two electro mag- for list. John L. Bowman, Reinhold., Pa. "Practical Electricity," $2; WANTED-- Crystoli detector and variable con- nets; all goods new; value $23. Exchange for denser by September 20 for portable set (2- switch FOR SALE -$14 electric railway, $5; $2 omni- good wireless receiving set. Write and tell what navy type tuner, detector and condenser), moving graph, $1; $8 worth Magic, $3.50; two $2 stamp you bave. Ray M. Casper, 821 E. Innis St., picture machine (electric), value $4.50; % -inch albums, $1 each. For particulars write Franklyn Salisbury, N. C. spark coil, in excellent condition. Thomas Stratford, Bentley Ave., Jersey City, N. J. EXCHANGE -Variable Condenser for Telegraph Steringer, 260 Hudson St., New York. FOR SALE -2 Electrolytic Detectors (new), $1 Instrument, Switch Block, Silicon Detector and FOR new 1915 Detector with sili- each; 1 Three Slide Tuner, $2; 1 Toy Motor, 50c. SALE-Duck's Fixed Condenser for Telegraph Instrument; Mur- con, 1 New Rotary Spark Gap; never been need. All in perfect condition. Miles F. Ham, 21 Crosby and Buzzer for ,St., Augusta, Me. dock Spark Gap same. Harold All for $5 cash, M. H. Chapman, Baldwinsville, Bonney, 103 Spruce St., Pana, ill, N. Y. FOR SALE OR EXCHANGE -100 Watt set, value $15; 400 watt impregnated condenser, $8; EXCHANGE -Solar bicycle lamp, cost $2.50, for HAVE '4 -inch Coil, zinc Gap, strap key, 4 -plite Davis battery motor, $4; Stevens single -shot ride, water motor, standard thread faucet. B. Bergman, condenser. Trade for loose coupler or Brandes $7. Write for list. Money or transmitting appa- 120 N. 109th St., Chicago, Ill. receiver and Double headband. Garwood, 84 King ratus wanted. Make offer. II. Smeltzer, Norwood, East. Toronto, Canada. Mass. FOR SALE OR EXCHANGE -Loose Coupler, tuners and other wireless apparatus; have a num- WANTED -To buy a few Geissler or vacuum ELECTRICAL --35 K.W. Westinghouse Alternator. ber of pieces. Make offer. William Leaky, 2800 tubes, also an X -Ray tube. Albin Lundquist, right for a small town plant, $300 in payments of Snyder Ave., Philadelpbia, Pa. Cable, Wis. $20 per month. 18 K.W. 220 volt direct current generator will carry 900 regular 16 candle Tungsten FOR SALE -Entirely new pumping outfit, 1% EXCHANGE -One Companion Lathe and Scroll lamps, $200 in payments of $15 per month. 16 H, P. engine, 10 -foot belt pumpjack, $26; good saw in good shape, price, new, $8.50, for 2-inch cells storage battery in good condition $35. Elec- coaster brake bicycle, $9. Frank Fish, Geary, Spark coil or other electrical apparatus. Leland tric Bath Cabinet $25, Box M, Troy, Ohio. Okla. R 1. Jones, Warrensburg, Mo,

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