EE Mar 1928 .Pdf

BROADCA ST

EXPERIMENTER PUBLISHING, COMPANY, NEW YORK, PUBLISHERS OF RADIO NEWS - RADIO LISTENERS' GUIDE - - FRENCH HUMOR - AMAZING STORIES

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Formerly ELECTRICAL EXPERIMENTER COMBINED WITH "THE EXPERIMENTER" Member Audit Bureau of Circulations EDITORIAL, ADVERTISING AND GENERAL OFFICES: 230 Fifth Avenue, New York City Published by Experimenter Publishing Company, Inc. (H. Gernsback, Pres.; S. Gernsback, Vice -Tres. and Treas.; C. E. Rosenfelt, Sec'y. Publishers of SCIENCE AND INVENTION, RADIO NEWS, RADIO LISTENERS' GUIDE, AMAZING STORIES and FRENCH HUMOR

Editorial Staff Contributing Editors HUGO GERN SBA( K, Editor -in -Chief. Astronomy- Automotive Sub George A. Lures IL WIN FIELD SEcoR, Managing Editor Dr. Donald H, Menzel, Ph.D., Lick Observatory; W. J. Luyten, of the Harvard College Observatory. Radio- A. P. Perk, Herbert Hayden. T. O'CON OR SLOANE, PH. D., Entomology and Allied Subjects- Magic and Psychic Phenomena- Associate Editor. Dr. Ernest Bade, Ph.D. .toseph Dunninger, Joseph F. Rinn, Edward Merlin. JOSEPH H. KRAUS, Field Editor. Physics- Foreign Correspondents- PAUL WELKER, Radio Editor. Dr. Harold F. Richards, Ph.D., Ernest K. Chapin. Dr. Alterai Gnadenwitz, Germany; Dr. H. Becher, SI.A., Dr. Donald H. Menzel, Ph.D. Germany; C. A. Oldroyd, England; S. Leonard Bas- S. GERN SPACE. Wrinkles Editor. tin, England; Count A. N. 311 rzaoff, France; Hubert Chemistry- Slouka, Czecho-Slovakia; P. C. van Petegem, Hol- W, J. ROMAINE, Art Director. Raymond it. Wailes, Dr. Ernest Rade, Ph.D. land; Richard Neumann, Austria. IN APRIL ISSUE CONTENTS OF THIS NUMBER Real Spirits? GENERAL SCIENCE S. & I. Three -Tube A.C.-D.C. Set 1020 in- Editorial 977 By Paul Welker The very latest European By Hugo Gernsback ,Radio Oracle .. 1021 vestigations on the production The Case of the S-4 978 ASTRONOMY of spirits or materializations at By H, 11'infield Secor Largest Associate :Member, American Insti- Reflecting Telescope in Europe 994 spiritualistic séances will be \ i.siting Other Planets 998 tute of Electrical Engineers By James Nevin published in picture and story. 'thought Konzentrator-latest Swindle 981 Miller By Hugo Gernsback AUTOMOTIVE Do Animals Grow New Limbs? Member, American Physical Society What Makes an Automotive Mechanic? 991 Longest Concrete Bridge at New Orleans 983 By Henry Townsend One of the greatest questions New Boat Propelled Like Fish 983 Motor Hints 1004 of all time is-why can't a man Fish Harvester 987 Conducted by George A. Liters Scientific Progress 988 HOW grow a new limb, if he should Strange Hobbies and Crafts of Successful Men 992 -TO-MARE -IT lose one in an accident? How By George H. Doer Miniature Cities-Clow Built 997 respond under such con- The Month's Scientific News Illustrated 99( By Lee Black, the Man Who Builds Them animals By George 14'all Model Department-Prize Cup Each Month 1006 ditions will he explained by an The Metal Emperor-Sixth Installment 1000 HIow to Make a Barometer 1009 expert. By A. Merritt By Raymond B. Wailes Can Y'ou Answer These Scientific Questions? 1002 Magazine Mysteries 1010 Sea Serpents? Magic-a Monthly Feature 1003 By Bert Douglas By Dunninger Howo-Make-It-t Department .. 1012 Do you believe the stories told Everyday Chemistry 1005 Wrinkles. Recipes and Formulas ...... _. 1014 for generations regarding im- By Raymond B. Wailes Edited by S. Gernsback Experimental Chemistry and Electrics 1007 MEDICAL mense sea serpents? The latest Readers' Forum 1013 appear Can Siamese Twins Be Separated? 984 scientific explanation will Scientific humor 1022 By Joseph Latest Patents 1023 II. Kraus in the next issue. Water asid Its Impurities 1008 Oracle ..... 1024 By Dr. E, Bade Patent Advice - 1034 Moving the Tower of Pisa AERONAUTICS RADIO The greatest engineering feat Eliminating Fatal "l'ail Spin" 990 imaginable - necessitated by Radio Guides Torpedo Boat 1015 By C. A, Oldroyd foundation New Radio Devices 1017 Air Currents Now Photographed 994 water undermining The Laboratory Shielded Super 1018 Flying Blind 982 of leaning structure. By Philip Radteelsky By G. K. Spencer

HOW TO SI-IiSCRIBE FOR "SCIENCE AND INVENTION." Send your name, address and remittance to Experimenter Publishing Co., 230 Fifth Ave., Ness York City. Checks and rummy orders should be made payable to Experimenter Publishing Co., Irae. Mention magazine desired, inasmuch as we also Publish RADIO NEWS, A31.5ZING STORIES, RADIO LISTENERS' GUIDE; and FRENCH HUMOR, a weekly. Subscriptions may he made in combination with the other publications just mentioned at special reduced club rates. Send postal for club rate card. Subscriptions start wit h the current issue unless otherwise ordered. ON EXPIRATION of your subscription the enclose a renewal blank in our last number to you, and notify you by mall. 'Then, unless ive receisr your order and remittance of a renewal, delivery of the magazine is stopped. SCIENCE AND INVENTION is published on the 10th of each month. There are i2 numbers per year. Sub- scription price is $2.50 a year in U. S. and possessions. Canada and foreign countries, $3.00 a year. U. S. coin as well as U. S. stamps accepted (no foreign coin or stamps). Single copies, 25e each. All communications and contributions to this journal should he addressed to Editor, SCIENCE ANI) INVEN- TION, 230 Fifth Ave., New York City, N. Y. Unaccepted contributions cannot be returned unless full postage has been included. ALL accepted contributions are paid for on publication. SCIENCE AND INVENTION Monthly. Entered as second-class matter May 10, 1924, at the Post Office at New York, N. Y., under the act of March 3. 1879. Additional entry at Dunellen, N. J. Title Registered at the Patent Office. Copyright, 1928, by E. P. Co., Inc., New York. The Contents of this Magazine are copyrighted and must not be reproduced without giving full credit to the publication. SCIENCE AND INVENTION is for sale at all newsstands in the United States and Canada. European Agents, S. J. Wise Et Cie, 40 ,Place Verte, Antwerp, Belgium. ADVERTISING REPRESENTATIVES-L. F. McCLI7RE, 720 Cass St., Chicago, Ill.; DAVIES, DILLON & KELLY, 15 West 10th St., Kansas City, Mo.; T. F. MAG1tANE, Park Square Bldg., Boston, Mass.; HARRY E. HYDE, 548 Drexel Bldg., Philadelphia, l'a.; A. J. NORRIS HI7.1. l'Os, 5 Third St., San Francisco, Calif., 412 West Gth St., Los Angeles, Calif.; Leary Bldg., Seattle, W) eh

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INDEX TO ADVERTISERS

PAGE CAGE :t+ PAGE F L P A Parks Woodworking Machine American Chime Clock Company 1058 Fairbanks Tailoring Company .. 1046 Laboratory Materials Company 1044 Co., The 1061 American Detective System 1046 Farmer Burns School 1054 Lacey & Lacey 1036 Perfect Penmanship Institute 1052 American School 969, 1058 Fawcett Publications. Inc. 974 Lancaster & Allwine 1036 Petroleum Enginee-ing Univer- American School of Aviation .. 1053 Federal School of Illustrating 1037 LaSalle Extension University, sity 1046 American School of Music 1041, 1050 First Hawaiian Conservatory of 1036, 1050 Plymouth Rock Squab Company 1050 American School of Photog- Music 1046 Laurel house 1057 Polacleik, Z. IL 1036 raphy 1049 Fisher Mfg. Co., Adam 1036 Leonard, A. O. 1053 Polk & Company, R. 1.. 1050 American Telephone & Telegaph Franklin Institute 1040, 1043 LePage's Craft League 1060 Popular Chemistry 1046 Co. 1039 Franklin Publishing Company .. 1049 Liederman, Earle E 1051 Press Guild, Inc 1047 Anita Company 1050 Eraser, Irving 1051 I.oftis Brothers & Company 1049 Publishers Clas í1,v;1 Service, Applebaum. A. L. 1036 The 1059 Artcraft Studios 1056 G Mc R Audel & Company, Theo., Inside Back Cover Gilson Slide Rule Company 1044 McCathran, Irving i,. 1034 Radio Association of America 976 1018 Given, E. S. 1046 McGraw -I I ill Book Co., Inc 1033 Radio Equipment Company 1054 Automatic Rubber Company Radio Institute of America 1055 Aviation Institute of U. S, .A 1051 Glover, L. 1045 Greer College of Automotive M Radio Producer Company , 1052 B Engineering 1038 Radio Specialty Company 1027 \Iaxson, F. P. 1050 Randolph & Company 1034 Balda Art Service 1051 Metal Arts Company 1055 Rhodes Manufacturing Company, Bathe Manufacturing Company 1051 H Metal Cast Products Co, 1046 1040 Back Cover Bell Perfume Company Iamilton-Carr Radio Corp. I055 Midwest Radio Corporation 1045 Ross -Could Company 1041 Blancke Auto Devices Company 1055 Hamilton Institute, Alexander 1046 Miller, Monroe E. 1036 Bliss Electrical School 1050 Mills, Albert 1050 S Hardin -Lavin Company 1060 School of Engineering Mil- Block Hermanos 1042 I1aywood Tire Equipment Com- Milo Publishing Company, The 1030 of Boeing M. L. 1056 Milwaukee School of watch waukee 1049 pany 1042 Seaside Hotel, The 1046 Brief English Systems, Inc. 1028 iligh School Ilome Study Bu- Repairing 1046 Bryant & Lowry 1036 Miniature Ship Models 1051 Seaver -Williams Company 1044 reau 1056 Sinclair, 1053 Buescher Band Instrument Com- -Hobart Brothers 1054 Movie Operators School 1052 James pany 1032 Munn & Company 1036 Stewart Automotive Trade !foe/tack, Paul 1036 School 1026 Bureau of Inventive Science 1034 Ilolton Company, Frank 1053 Bush, David V. 1051 N Stransky, Mfg. Co., J. A 972 Strongfort Institute 1057 C I National Automotive and Elec- Strout Agency 1051 Cervenec System. .\. S 1049 ideal Aeroplane & Supply Co 1052 trical School 1052 T Chemical Institute of N. Y., Inc 975 Impelerator Corp. 1061 National Carbon Company. Tamblyn, F. W. 1057 Chicago Correspondence School Independent Electric Works 1055 Inside Front Cover Thayer, Jim 1060 of Music, Inc. 1060 -ukograph Company, The 1043 National Radio Institute 971 Titus 1060 Coleman, Watson L. 1036 International Club 1061 National School of Cartooning 1052 Townsend Laboratories 1055 Consrad Company, Inc., International Correspondence National School of Watchmaking 1050 Trilety, M. 1046, 1057 1031, 1040, 1044, 1056, 1064 Schools 1039, 1042, 1045, 1048, 1058 New Age Illustrated 1064 New Method Manufacturing Co. 1041 Cox, S. J. 1056 International Typewriter Ex- U Coyne Electrical School 973 change 1049 New York Electrical School 1041 United I'ortrait Company 1060 Curtan-Quickstart Company 1051 New York Institute of Photog- Universal Plumbing School 1053 J raphy 1048 U. S, Swiss Agents 1058 D North American Finance & De- V Company 1052 Jenkins Corporation 1052 velopment Corp. 1034 Denver Optic North American Institute 1029 Vandeventer, II. 12, 1036 Douglas, Lyle 1050 K Norton Dryer, Prof. J. .\, 1041 Institute 1050 w Kelly, T. W. 1045 Waco Tool Works, Inc. 104.3 E Kelsey Company. The 1056 o Whirlwind Company 1052 Evans & Company, Victor J. .... 1037 Kitthin, Edgar M. 1036 O'Brien, Clarence A. 1035 \Pollensack Optical Co . 1052 66 very 3,000 MilesThis Amazing Little Device Buys Me a NewTire...

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As the driver pitched forward from his seat, a gun crashed from inside the coach.

THE DEVIL'S DOUBLE-CROSS (A Gripping Story of the Rio Grande by Frederick Nebel)

WHEN Sheriff Sid Gade forgot his than had ever been known along the oath of office long enough to Rio Grande. It took the roaring guns listen to the voice of the tempter and of two Senora cow -pokes to make the agreed to rob a stage coach carrying sheriff see the light but he did, and a fortune in gems, he stepped into vindicated himself in one of the more treachery, intrigue and killings greatest gun -fights you've ever read. THE DEVIL'S DOUBLE-CROSS appears in the MARCH issue of

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STER, RAOUL WHITFIELD AND Address OTHERS. -J Science and Invention for March, 1928 9' What These Have Done YOU CAN DO! "Since I have been studying with your school I have been appointed chemist for the Scranton Coal Co., II: } ou are dissatisfied with your present testing all the coal and ash by proximate analysis." money, if -Morlais Couzens. work, if you wish to earn more you want to get into a profession where the "I also have some news for you. 1 have been made demand for trained men is increasing as the assistant chemist for the concern I am working for." -A. G. Delwarte. Chemist plays a more and more important role in the industrial life of this country, let us "1 am now cleaner and dyer for the above named company. My salary is almost double what it teach you Chemistry. was when I started the ourse." -E. H. Lasater.

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DINING the Radio Association enables you to cash Doubled Income in Six Months in on Radio now! Follow its success -proven plans, "I attribute my success entirely to the Radio Associa- and you can earn $3 an hour, in your spare time. tion," writes W. E. Thon, Chicago, who was clerk in a from the very first. Over $600,000,000 is being spent hardware store before joining. We helped him secure yearly for sets, supplies, service. You the managership of a large store at can get your share of this business a 220% increased salary. and, at the same time, fit yourself for the big -pay opportunities in Radio. What a Membership can "In 1922 I was a clerk," writes K. O. Do for You Benzing, McGregor, Ia., "when I enrolled. Founded on a New Idea Since then I have built hundreds of sets- from 1 -tube Regenerative Superhetero - I -Enable you to earn $3 an hour to dynes. I now Members of the Association do not upwards in your spare time. am operating my own store wait for months before make and my income is 200% greater than when they 2-Train you to install, repair and I joined the Association. My entire success money out of Radio. Without quit- build all kinds of sets. is due to the splendid help it gave." ting their jobs, our members are 3-Start you in business without Easiest Way earning $25 to S75 a week spare time capital, or finance an invention. Into Radio radio sets, by building "tailored" 4-Train you for the $3,000 to $10,000 If ambitious to become a Radio Engineer, serving as ''radio doctors," selling big -pay radio positions. to fit yourself for the $3,000 to $10,000 ready built sets and accessories, or opportunities in Radio, join the Association. 5-Help secure a better radio position It gives you a following one of the many profit - at bigger pay for you. comprehensive, practical and making plans of Association. theoretical training and the benefit of our the 6-Give you the backing of the Radio Employment Service. You earn while you Association. learn. You have the privilege of buying Earned $500 in Spare Hours radio supplies at wholesale. You have the A MEMBERSHIP NEED NOT Association behind you in carrying out your Hundreds earn $3 an hour as "radio COST YOU A SINGLE doctors." Lyle Follick, Lansing, CENT ambitions. Mich., has already made $500 in spare ACT NOW-if you wish Special time. Werner Eichler, Rochester, Membership Plan is earning $50 a week for spare time. F. J. N. Y., To a limited number Mo., is in spare of ambitious men, we will give Special Buckley, Sedalia, earning as much Memberships that may not-need not-cost you a cent. To time as he receives from his employer. secure one, write today. We will send you details and also We will start von in business. Our cooperative plan our book, "Your Opportunity in the Radio Industry." It will open your eyes to the money -making possibilities of Radio. gives the ambitious man his opportunity to establish Write today. himself. Many have followed this plan and established radio stores. Membership in the Association has increased the salaries of many. Scores are now connected with big radio organizations. Others have RADIO ASSOCIATION OF AMERICA, prosperous stores. 4513 Ravenswood Avenue, Chicago, Ill. Dept. SN -3 A year ago Claude De Grave knew nothing about Radio. Gentlemen: Today he is on the staff of a famous radio manufac- Please send nie, by return mail, full details of your Special Membership Plan, and also copy of your book, "Your Opportunity turer and an associate member of the Institute of Radio in the Radio Industry." Engineers. He attributes his success to joining the As- sociation. His income now is 350% more than when Name he joined. Address City State MARCH, 1928 Volume XV an 11 Stien et No. Whole No. 179 iffgtti®fl HUGO GERNSBACK, Editor -in -Chief H. WINFIELD SECOR, Managing Editor DR. T. O'CoNoR SLOANE, PH.D., Associate Editor Editorial and General Offices - - 230 Fifth Avenue, New York

"Those Who Refuse to Go Beyond Fact Rarely Get as Far as Fact" - - - HUXLEY

TIIE GAIRET INVENTOR

By HUGO GERNSBACK

as to the statement appeared, rather ill-advisedly, that no boss to dictate to him, and he is responsible only to himself ECENTLY it is no the day of the "garret inventor" was gone. It was pointed the results. If the invention proves to he a disappointment, it is success, he may out, in all sincerity, that no great inventions could possibly one's business except the inventor's; while if a of examples from the small inventor in the future, because inven- or may not reap the full reward of his labors. Dozens come the garret inventor is today, so the story ran, is organized in the big industrial labora- can, of course, be given to any doubter that tion be with us. There is no tories, where everything worthwhile is now invented. still with us, and undoubtedly will always reason for supposing that he will be exterminated by the professional The story sounded plausible enough, because in all of the labora- corporation inventor. Quite the contrary. industrial companies, research scientists are busy, tories of our large inventions upon which day and night, in inventing and perfecting new devices. It is also Take, for instance, one of the recent great the research scientists and inven- men are just now working feverishly; namely, television. There quite true that in such laboratories with very little tors have every necessary tool, all apparatus, and, what is far more was Baird, of London, who, single-handed and all of which are used in the money, actually did invent television before it was demonstrated in important, practically unlimited funds, and Tele- of science and invention. So it would seem, offhand, this country by the engineers of the American Telephone furtherance C. Francis Jen- that such being the case the small inventor is doomed. graph Company. Likewise, even before television, kins, of Washington, had also achieved certain results in its direc- Actually it does not work out that way in practice, for very tion. And neither Baird nor Jenkins were employed by any cor- paid inventor in the labora- indi- simple reasons. In the first place, the poration ; but they were, and still retain the status of private tory, as well as his brother, the scientific investigator, usually works viduals. Then, of course, there was Armstrong, who was credited along certain lines, on certain specific problems. They are usually with the invention of regeneration, a most important radio develop- working for a company whose interests lie only in a narrow and ment. Recently a large syndicate paid a million dollars for the inven- restricted field. Such laboratories seldom, if ever, allow their tion of the Photomaton, which takes photographs of you automatic- workers to turn loose in any direction that their fa:Lcy dictates. ally while you wait. Here, again, is the garret inventor, plodding Ninety-nine times out of one hundred, the research and invention along in the unbeaten path. staff will have its hands full with problems bearing directly on or another. It is quite true Very recently, Dr. Theremin, a young Russian physicist, discov- the business of the company, one way of his many new and useful inventions are developed, ered his new process of creating music simply by the waving that in this way was behind him to perfect but most of these pertain directly to the product or products of the hands. No huge and expensive laboratory particular corporation. Once in a while a by-product invention this idea. It was all done in his own spare time. comes along, which by-product may become the big thing later on, But of course these are all exceptions, being mostly inventions of a because, in the very nature of things, a new invention sometimes gives spectacular nature. What about the small garret inventor, the fellow rise to dozens of others which spread out, fan -wise, from the who invents a new can opener, the fellow who tinkers around until original invention. But this does not happen every day, nor is it he perfects a new door stop, the man who makes a new cigar lighter, the usual run of things. the inventor who creates a new radio dial, the man who makes a ice pick, a research scientist of a large cor- new bottle cap, the man who makes a new self -striking It is comparatively rare that the spectacular inven- will tell his superiors that he wants to develop a certain idea and dozens of other inventions? It isn't always poration Indeed, it is usually the small a new invention, which may be entirely foreign to the corporation that "brings home the bacon." on is likely to make its owner tion's business. It would mean, immediately, that the man who had invention, which, if it finds a market, an rich. And usually the big corporations, with their research labora- the idea would have to he kept on the pay roll, working on such They would have to expend funds in a tories, do not waste much time on these small inventions. invention, while the corporation and there are thousands and direction in which it was not necessarily interested. If the head, or leave that to the garret inventors, interested in such a thousands of them in this country, who reap their yearly rewards manager, of the corporation is sufficiently inventions. procedure, it may come about that the inventor will finally work out with their small, but practical and necessary his idea, but such a case is not often heard of, and is decidedly the And let no one think that these inventors are decreasing in num- exception. ber Quite the contrary. They are busier than ever, and their suc- as years go by. The in the garret has no such limitations. Like as cesses are getting more and more pronounced But the inventor hundreds of such inventions are not, he invents for the pure fun of it in his spare time, and if he is weekly Patent Gazette, where week to week, bears glowing testimony a real dyed-in-the-wool inventor, he is not at all interested in whether described and recorded from there is any immediate monetary reward in the invention. He has to this.

meters) on various scientific subjects Mr. Hugo Gernsback speaks every Tuesday at 9.30 P. M. from Stations W RNY (326 meters) and 2RAL (30.90 077 978 Science and Invention for March, 1928 PRESENT AIR SUd'PLY SYSTEM The Case CENTRAL AIRLINE! PRESENT EMER- OPENING FOR The Present Article Deals with GENCY AIR LINE DIVERS Buoys, and Other Devices- Opinion of Them

By H. WINFIELD MEN HERE AIR SUPPLY VALVE P editors have been flooded with IN E AC H COM PARTMENT -THE DAMAGED SECTION all kinds of ideas submitted by readers fur rescuing the crew of the sunken submarine S-4, as well as raising the PROPOSED EMERGENCY AIR SUPPLY vessel itself. Some of the best ideas submitted are here discussed, with the Navy De- partment's objections to most of them. In , lÍ EACH COMPARTMENT i a recent interview with one of the U. S. y HAS OWN AIR VALVES ONd Navy Department's officers stationed at New /C OUTSIDE OF HULL York, a great many of the Submarine salvage ideas and crew rescue methods here illustrated were discussed. This officer stated that out of several thousand ideas submitted by various civilian inventors, only two of the suggestions proved to be new and really FRESH worthwhile. These ideas had been for- AIR SUPPLY. ISOLATING VALVES warded to the naval officers in charge of 1 the salvaging of the S-4 off Provincetown. FAIR HOSE FROM WHY NO TENDER BOAT WAS USED TENDER ON SURFACE TRAPPED CREW THE public press has been very caustic UNSCREW PLUG on the point that the submarine S-4 fEszPEEn rsavmzs 1==u1:1 ON SIGNAL »a `0 should never have undertaken a prac- DIVER CONCENTRATEDTH tice dive off Provincetown, R. I., THREADS RODED ship on the scene, to warn SLEEVE FOOD AND OXYGEN without a tender INTO HOLE other vessels off the course. Other criticisms OXYGEN THREE EXTERNAL have been to the point that the Coast Guard TANK AIR VALVES AC- Destroyer Paulding, which rammed the S-4 THREADED CESSIBLE TO and caused it to sink within a few moments, PLUG TO BE DIVERS REMOVED had no busiruess in that vicinity at the time. BY DIVER. As was pointed out by the naval officer w-- whom the writer interviewed, the Navy De- partment does not usually operate in con- GASKET -GASKET junction with the Coast Guard, which may or may not be a partial excuse for the sink- 4-- OUTER 3 VALVES ARE USED ing of the S-4; and further, it was stated SHELL AS SUBMARINE MAY LIE that in the regular peace -time maneuvers of DOUBLE HULL NOT ON KEEL submarines, such as will take place off Cuba A simple scheme is shown above by which and Panama shortly, the sub -sea craft make divers could pass concentrated food and oxygen into the trapped submarine. Diver practically all their dives and maneuvers unscrews the outside plug and connects without a tender vessel to warn other ships the special cylinder shown; on signal the off the course. As this officer put it-a crew unscrews the inside plug, when air and food are supplied to them. HOLE WOULD BE CUT HERE,..''' ;;;o

tPATH THROUGH

, ¡MUD BLOWN BY ;STREAM OF WATER Ii GERMAN METHOD t A COM PRESSED AIR BLOWING WATER OUT OF COMPARTMENTS

German method of using a twin -bull submarine salvage craft is shown in circle. If sufficient water could have been blown out of S-4, bow would have come an, as shown. 979 Science amid Iuvrcntiou for March, 1928

of the S-4 . PIERCING NEON K.3 HT BEAMS FROM

- BUOY Lifting E) i - Compartment Valves, and the 1\ßt\ y Department's Is Also Given

SLCOR WARNING Biitsy (CAN 8E REl EA4F-D submarine which cannot take care of itself AT 'SEA E3OT T v Iv1 FOR in wartime without a tender standing by, is t7t`'iríîESS SIGNALS a pretty useless weapon. But m peace time I t*t CODE) it is not apparent just wily the boats course should not he patrolled. In view of the fact that there is apparently no positive form of signal now in use /TOW LINE - on U. S. submarines, which indicate when / (TELEPHONE CABLE TO a sub -sea vessel is about to conic up and ì SUBMARINE break the surface of the water, this argu- INCLUDED) ment does not sound so good. The Navy spokesman stated that even though Prof. Vessenden stressed the use of the sub --i oscillator for sending sound wave signals under water, as well as the -fact that submarines are supposed to har,.1 sensitive listening devices for hearing the propellers on SUBMARINE ships a mile or mmi re away, that owing to the noise of the submarine's own propeller, CHECK and other extraneous noises such as sur face VALVE AIR HOSE' or wave action, that a man stationed at a One inventor's scheme of a marker buoy, \1I//, which could also be released as a warning listening post on the S-4 for example, prob- signal when rising. ably could not have heard the churn of the propellers on the rapidly approaching destroyer Paulding. As all of the crew were MAGNET CABLE lost, it will probably never be known ap- AIR SUPPLY whether a man was listening for an FOR CREW proaching vessel. It is usually necessary to in ELECTRICAL stop the propeller on the listenhig ship SUPPLY order that the sounds from another ship's //lI\\ screws can be clearly heard. It is of course CHECK VALVE PUMP TO not feasible to stop all the machinery on a RUBBER FORCE FOOD the sur- WATER TELL- THROUGH submarine when it is rising toward TALE LIGHTS TUBE face, as the screws have to be kept going. FOR DIVER / A submarine does not normally rise straight OXYGEN m (C up or down, but is kept in motion by means

of the screw -s as it is coming up or THERMOS FLASKCONTAI N' NG NOT going down, the angle at which the LIQUID FOOD bow is pointed being determined by the position of the steering vanes fore and aft. (Continued on nest page) The author's suggestion for a special water -tight drilling bell, which would enable air, liquid food and oxygen to be passed to trapped crew. The method of operation is obvious. SA LVAG E SH1P

COMPRESSED AIR PUMPED TO CREW

AIRDIVER TO'

/SAILOR IN HELMET BEING ECIAiFe E HOISTED TO SURFACE C,OMPRESSE D AIR HOLDS WATER BAÇK HOLE THROUGH DOUBLE HULL FOR PASSAGE OF CREW IN HELMETS S3MON AK E'S ME i ^©

411,

Simon Lake's method of rescuing the trapped men on the S-4 is shown in the circle; this is a good method where compressed air can be pumped into the occupied compartment. 980 Science and Invention for March, 1928

marines, that these additional salvage air out to the writer, however, that the com- SALVAGE SHIPS OR WINCHES DERRICKS valves in every section of the submarine mon salvage air line on the S-4, had more would cause still more trouble from leaks than one external opening to which divers whenever a submarine dives, or even under could connect air supply lines ; in spite of ERIPARATE normal conditions when running awash. this, however, nothing could be done for the EYES BUILT ARLES. INTO STEEL As our drawings clearly indicate, the S-4 men in the torpedo room of the S-4, owing FRAME had a salvage air line running to all the to the rupture of the vital part of the emer- compartments in the vessel, this common air gency air system, as was aforementioned. line communicating with an external valve A valve in each compartment would have on the conning tower, which was available saved the six men in the torpedo room; that STRAIN ON EACH EYE to divers descending to the wreck. seems certain. ANO CABLE ONLY MUD\ UCTION If a submarine accidentally sinks ordi- FRACT ON OF TO- BROKEN BY SUPPLYING AIR THROUGH SIGNAL TUBES TAL LOAD COMPRESSED AIR narily, without badly being damaged in the J mid -section, as was the S-4, due to being ABOUT four and one half days after rammed by the destroyer Paulding, then this the S-4 went doze'n off Provincetowu, common air relief line, running to all the and at a time when no further signals were compartments, is a fine idea. heard from the trapped men, the divers were In the case of the S-4, as will be remem- able to pump air into the torpedo room bered, this salvage air line was ruptured through the S -C signal tubes. The diaphragm on the hull was removed for this; purpose and air forced in through the small metal tube leading into the torpedo compartment. The great, question now arises of course, as to why this was not done during the first twenty -f our hours after the submarine went down, when divers were sent down. Not OPTIONAL LIFTING METHOD WITH POWERFUL CRANES only was air finally pumped into the torpedo room through the small signal tube, but Two optional methods suggested for raising samples of the air were periodically trapped submarines by means of cables attached to and analyzed, in eyes or rings securely fastened to the frame- order to determine the work of the vessel. The principal point is to amount of poisonous carbon dioxide in the have a sufficient number of rings. air coming; from this chamber. The testimony of Lieut. Commander Ellsberg before LIFTING EYES-PRO AND CON SUBMARINE ON SURFACE the Naval Court of Inquiry, showed that SEVERAL thousand civilian inventors HEARS HAM- MER SIGNALS signs of life (taps) from the torpedo room have sent to the editors of this magazine, had been obtained by the diver on the day newspapers and to the Navy Department, THROUGH OS C I LLATOR after the S-4 sunk. Commander Ellsberg the idea that suitable lifting eyes or hooks ONEOF CREW DIAFRAMS. HAMMERING blamed rough weather for the delay in pass- should be placed on all submarines, so that in ON STEE L SHELL ing air through the signal tube. the event that one of these craft becomes crippled and lies on the bottom, divers can v--- SOUND WAVES RAISING THE S-4 quickly descend and hook on cables and the AS the illustration at the start of this submarine lifted. article shows, the first idea uppermost The Navy Department's emphatic reply to e-ANCHORED in the naval officers' minds was to try and this proposition is to the effect that eye- GUIDE LINE raise the bow end of the sunken submarine bolts were fitted into the frame of sub- by attaching several air lines, so as to blow marines some years ago, on the smaller size DIVER CAN HEAR out any water in the compartments; and craft; but in actual tests they did not prove SIGNALS thus by making the submarine sufficiently successful. Several years ago one of the buoyant, enable it to rise, at least one end submarines so fitted with eye -bolts sunk, of it; all or most of its normal buoyancy and when the cables were attached to the thus reestablished. lifting eyes, some of the bolts pulled out; After pumping air into the submarine for and further, the submarine broke up, drown- some time, it was decided that owing to ing all the crew. The naval experts point the damage to the S-4, this condition would out that this submarine was a much smaller not occur, and the next plan was to use the craft than the modern type, and they are not, pontoon meth od of raising the submarine. therefore, at all desirous about trying eye- \ \ \` ` \ \5 (Col tinned on page 1055) bolts or hooks for attaching cables to the I extremely heavy modern submarine craft. I I I I I II DIVER`r It is the idea expressed by many civilian k INSIDE AOORSHUT engineers however, that if a sufficient num- FOUR TORPEDO TU BES. ber of eye -bolts were placed on the sub- TWO"BLIND"SUBMARINES CAN nY._ ABOUT 2X20 FEET Vie TALK BY SOUND WAVES SENT jj;&4 c marine, these bolts being properly anchored THROUGH THE WATER FROM Loki in a well designed frame; that a sufficient OSCILLATOR DIAFRAM IN SIDE i., ' OF HULL t number of cables could be attached to sub- J FOOD AND OXYGEN äóöß divide the strain, and thus safely lift the How hammer knocks on the hull of the S-4 submarine. It probably would be necessary were picked up by the oscillator diaphragms, mounted in the hull of the submarine S-8, INSIDE DOOR OPEN in many cases, to break the mud suction by floating on the surface. Lower diagram shows means of high pressure water streams, when how one "sub" communicates with another OUTER DOOR the lift was to be made. by under water sound waves. SHUT TORPEDOTUBE ki VALVES IN EACH COMPARTMENT when the Paulding struck the unfortunate THERE probably never were so many peo- craft, and it was discovered after several WATER FROM TUBE J ple imbued with the same idea, as in hours that the air being pumped into this the case of the S-4 disaster, when one out common pipe line was not reaching the men of every three people we met, strongly sug- entrapped in the torpedo room in the for- gested that the men trapped in the torpedo ward part of the submarine. An unsuccess- LISTENING room of the S-4 could have been saved, if ful effort was made to repair the damaged DEVICE line by a piece of hose. each of the separate compartments in the air means of RAIRSUPPLY submarine had been fitted with a valve com- It is the firm belief of the editors that in municating spite of all the arguments against the com- with the external shell. DIVERS PASS- The idea of these separate compartment partment air valves by the Navy Depart- ING FOOD, OX- valves is of course, that the diver simply has ment, and to which divers could connect air YGEN AND to unscrew a plug, for example, and connect lines in case of an accident ;that these could AIR THROUGH LISTENING an air hose from a salvage boat above. be properly designed and provided with suit- TUBE in is that able tell -tale signals, so that the commanding Another idea this direction 1 liquid food could be sent down the hose at officer on the submarine would know at all intervals, and the then thus kept alive in- times, whether these valves were fully closed definitely, or until it was possible to raise or not. The naval officer whom the writer the submarine and rescue them. interviewed at New York, agreed that this 1111111111111111) Navy Department to idea of the individual compartment valves Two schemes which might have saved the The objection of the lives of the S -4's crew. First-d ver supp es placing valves in every compartment is that was a good one, and he could not see why food through torpedo tube; second-oxygen there are so many valves on modern sub- this should not be employed. He pointed and liquid food fed through S -C signal tube. Science and Invention for March, 1928 981 Thought "Konzentrator" Latest Swindle German Device Supposed to Stimulate Thoughts, Actually Does So-But Not the Way One Expects

By HUGO GERNSBACK Member American Physical Society

THAT Barnum was right, and will be Actually, only the two German sil- right for generations to come, is best ver wires touch the temples. There proven by the scientific fakes and can be no electrical action, because swindles that seem to be on the in- there is no electrical circuit; sim- crease, rather than on the decrease. As ply because the metal discs have Barnum said, "The public likes to be hum- no connection with each other, be- bugged," seems to hold just as good in this ing very nicely insulated by the day, except that more fools seem to he born cheap leather strap that goes now than ever before. If there were not, against the forehead. A piece of all of the fake devices that seem to abound mercerized tape holds the device to could not exist. We have exposed many the temples. scientific swindles in the past, but the one that we present to the unenlightened world opening the discs, one finds today possibly takes the prize. that the piece of German silver wire which goes around the IN some of the other devices we exposed, cork is not designed to make con- at least there may always be some re- tact with the metal discs them- mote question in someone's mind that "there selves ; so whatever the action of may be something to it after all." In some the German silver wires is, it cer- of those which we have described and ex- tainly is not electrical, it is not posed in SCIENCE AND INVENTION, there was magnetic, it certainly is not chemi- at least some force, such as electricity or mag- cal-in short, it is nothing that netism-always the ever mysterious-that was anyone knows anything about or likely G. C. B. Rowe demonstra-itg how the lurking behind some shiny knob or that could ever will. "Konzentrator" is wo -n. TLi: s_mple de- be attached to a light socket, and at least The capsule that is placed on the vice is claimed to stimulate thought and give a physical demonstration that some- center of the forehead and which, perform the other seven vor-cers. thing actually happened in the device. But as we said before, contains the col- The Thought Konzentrator, a German de- ored glycero-gelatine, does not make direct Do not loan your apparatus to ethers. Keep it for your own self. Head the enclosed Directions vice, which is now being imported into this contact with the forehead itself. Instead, carefully and you will have the power to seek. country, is without doubt the most prepos- the gelatine is contained in a shallow metal Use it in study. We all need n-nre and better piece of bunk that ever carne to these capsule, as shown in our illustration. Over brains. Study without concentration is useless. terous Konzentrator makes the btair, receptive and the shores. For the Konzentrator actually does this goes a cover, which is perforated. What memory retentive. Its electro -magnetic action nothing, neither electrically, nor any other mystic or cabalistic effect this glycerine is upon the brain mass and the pituitary gland it is to ascertain in a supposed to produce, is a deep secret. create vibrations, which will allow you in the way, that possible silence to swing into the cosmic in finite. physical laboratory. No one is to know anything about it. The Please spread the good news and help us to action of this glycerine certainly is neither serve others as we had the honor of serving you. THE KONZENTRATOR'S "INSIDES" electrical or chemical, nor has it any other Most sincerely yours, action that manifests itself in any labora- NOVOM CHEMICAI. COMPANY, T11E Konzentrator is composed of a neat tests, by (s) J.. E. Acker, tory as performed us. Owner. leather strap, two nice gilt discs, about Yet, harken to what the famous Konzen- 2 inches in diameter, and a small capsule, trator will do for you. When the device The following "directions," too, carne from which upon analysis proved to be colored was first advertised, we promptly sent for the Novom Chemical Co.: glycero-gelatine, a well-known substance. one, paying $10.00 for it. The device is for The two side discs are supposed to be worn sale by the Novom Chemical Company, 131 THE KONZENTRATOR metal does not over the temples, but the \Vest 41st Street, New York City, whose An invention of one of the most prominent Ger- touch the temple itself, for there is a cork letterhead states that they are importers and man Scientists in the fold of PsyehoTechnical disc face, over which runs a piece of Ger- makers of Psycho-Physico Accessories. (Continued on page 1060) man silver wire, as shown in the illustration.

CORRUGATED GERMAN DISC. :: SILVER WIRE Here is a photograph of the "Kon- Upon receipt of our $10.00, we zentrator" partly dissected for with following letter : closer inspection. Note capsule received the perforations. Dear Sir: Your favor with $10.00 for one Konzentrator has been thankfully received, and the apparatus shipped to you under separate cover. We hope that you will receive it in the condition it left us, which is excellent, and that it will bring you the enormous power it conveys to The details of the "Konzentrator." A cor- those who are earnest seekers after their rugated metal disk lined with a cork stopper, divine right of sons and daughters of the around which there is a piece of German sil- great Creator whom we call God. ver wire. It is held in a head -band, in the You can only derive the greatest benefit center of which we find a capsule containing from the use of the Konzentrator, and we colored gelatine. wish von the maximum of success. 982 Science and Inveniion for March, 1928 FLYING BLIND For First Time and Aviator Lands in a Complete Fog, Guided Only by Instruments, Thanks to New Ocker -Myers Flying System By G. K. SPENCER THE threshold has been crossed! A tions. Civil pilots everywhere recognize the human flyer has successfully and peril of flying through fog, with all land safely landed a flying machine entirely and sky marks obliterated, with the natural blind in a dense fog by the guidance horizon clouded from view. They know of instruments, instruments on which further that no human being can fly more than a experiment is already being pushed so that few minutes in such a fog, without losing all sense of position; without encountering vertigo, which causes the vestibular canals of the inner ear to deliberately lie to the brain; to tell the brain it is flying RIGHT when in reality the flight is LEFT, to tell it that ascension is being made, when in truth the air machine is diving dangerously to the surface below Until the experiments brilliantly conducted at the Presidio of San Francisco by Cap- tain William Ocker, oldest flying officer of the Army Air Corps, and Captain D. A. Myers, Flight Surgeon of the same Com- mand, it has not been realized that even the birds of the air suffer the same limitations as human beings in attempting to fly through dense fogs, that even sea -gulls and pelicans are found dead along the beaches after every great fog, killed as they flew in apparent security, downward, only to he crushed as they met the earth while their flight sense informed them they were flying The pilot coming out of the fog, was so com- safely. pletely fooled by his "flying senses," that he New revolving chair in which airplane pilots thought he was about to land the plane at the are tested. As long as the pilot concentrates spot marked X; instead, he finally discovered on the navigation instruments, all is well. that he was flying "vertically," and almost wrecked the plane on a cliff. NO "INHERITED" FLIGHT FIRST TAILSPIN( ' SENSE man In truth, there is no inherited flight sense. every or woman who flies, may with . t perfect safety enter and pass through fogs This from Captain Ocker, who has been without interruption to the aerial journeys. SECOND TAILSPIN with the United States Army since 1898, s (DELUSION) one of the first Army pilots, who learned EAR CANALS FOOL FLYER'S BRAIN CORRECT PATH the elements of flying in the first Curtiss The significance of this statement may flight school, and who was General William not be of as great import to the average e Mitchell's personal pilot (though the Gen- citizen, as it is to all the military and com- jj.'"FATAL PATH eral himself was one of the good ones) while mercial flying personnel, who today must i that officer was assistant chief of the Air suspend their flights the moment fog becomes Service at Washington. No instinctive flight thicker and more extensive than may be sense exists-even birds lack it. They fly flown through in a few minutes. mechanically, and every human who flies BIRD'S FLYING SENSE NOT PERFECT must do likewise, relegating what feel of the air he may have to a secondary but valuable Flying at all Military fields is suspended position. when fog descends ; the intrepid pilots who carry the air mail, upon encountering ex- Relying on "flying sense," one of the Pacific fliers undoubtedly flew into the ocean, instead "FLYING BLIND" BY THE NEW OCKER- tensive fog always land and await an oppor- of upward; due to the delusion of having been MYERS SYSTEM tunity to break through to their destina - in a second tail spin. After experimenting with more than 600 individual pilots, the first commercial tests of the Ocker -Myers system of flying were made with the pilots of the Pacific Air Transport, a company conducting the Air Mail lines between Los Angeles and Seattle, Washington, over the most extensive fog belt in the United States. The pilots of this company had been taking off in fogs, when telephonic reports from further along the coasts gave assurance that after a reasonable distance there Kvas a lift in the great Pacific fog fields. Even such take -offs possessed their element of danger, but the mails had to go through, and the persistence of fog during certain hours of the Pacific day, told us that if the planes did not take off many times while fog covered the Pacific slope, there would he no effectual air -mail service for the western coast cities. Accordingly, the Pacific Air Transport, which by permission of the Army Air Corps has its San Francisco terminal on Crissy Field, Presidio of San Francisco, was chosen for the first commercial experiments, and all the pilots of the company were instructed personally by Captain Ocker in the me- This picture, corresponding chanics of to that on the front cover, shows how a city appears when a pilot is what he wished accomplished, flying upside down. Due to the tricky action of the human senses, the pilot may and by Surgeon is flying upside only "think" he Myers in the principal in - down, and meet with disaster in consequence. (Continued on page 1031) Science and Invention for March, 1928 9S3 Longest Concrete Bridge at New Orleans The photo at the left shows one of the stages in the construction of the world's longest concrete highway bridge across Lake Pontchartrain, in New Orleans. At the left we have a view of the: world's largest pile-driver at work on the new bridge. This machine drives four of the eighty -foot concrete piles at one time, driving two alternately. -Illustration.,- courtesy New Orleans Assoc. of Commerce

: , 6 ::, <,tlllEid(#Ilt' 1111111 '

Above we have a view of the An illustration showing how the world's longest bridge, showing bridge will look when completed it in comparison to the Brook- appears at the left. There are lyn B r i d g e. The Brooklyn two bascule draw -bridges to allow Bridge is one and one -eighth ships to pass. The total cost of miles long, while the new bridge the bridge will be $5,000,000.00. extends five and one-half miles over water.

The world's longest highway The bridge is five and one- bridge is now being erected half miles long, thirty-five and will bridge Lake Pont- feet above the water. The chartrain, extending from the major portion of it rests on New Orleans shore of the lake huge concrete piles, weighing to Pointe Aux Herbes, on the twenty-five tons each, which northern shore of the lake. go down about seventy feet. New Boat Propelled Like Fish

ANEW, yet remarkably effi- The economical importance of the cient system of propelling Boerner effect is shown by the boats has recently been invented saving of seventy to eighty per by A. Boerner, of Germany. Tak- cent of the power or the attain- ing his observations directly from ment of higher speed. This in- fishes, the inventor was con- vention may be regarded as mark- vinced that the gills of the fish ing the birth of a revolutionary serve for propulsion, the expelled step in the line of boat propulsion, water flowing along the sides of which may be of great practical the body, thus driving the fish importance. It is marked by great ahead. The fins serve for the ingenuity in its simplicity and its maintenance of equilibrium and foundation is not one of mathe- the tail as a starter and rudder. matics, but of nature. Taking his The fish draws water, not only observations directly from the for breathing, but also for swim- fish, the inventor has thus been and drives it out through Above is a photograph of the new boat, with the inventor, A. Boerner, who able to build a boat, which is pro- ming of fast swim- the gills with increased velocity. built it. He conceived his idea by observing the movements pelled through the water in much ming fishes. The boat has a screw propeller located in the bow, in a as is the fish. On The fish therefore interposes a funnel -shaped opening beneath the water line. the same way medium between his body and the either side are gill -like openings. resistance of the water. Following out this test ship, which is entirely different from all line of thought, the inventor constructed his other boats. A screw propeller is located in the bow, in a funnel -shaped opening beneath the water. This specially constructed turbine, with a high speed of rotation, repro- duces the mouth and gill action of a fish. WATER the and SUCKED IN The water is sucked in by turbine driven out again. By passing through the . BOAT \\\\ NU - _ openings on the side of the ship, the water - creates a sort of whirlpool, which breaks against the corrugated side of the boat and produces effect of two streams of water ENG/NE DR/VEN an PROPELLER passing along the sides. By this operation, WATER PUMPED the bow resistance, which is created by the OUT HERE rapid movement through the water, is greatly AT X -X reduced. It is interesting to note that in the The above diagram shows the action of the pro- eighteenth century Bernoulli, and later the peller placed in the bow of the boat. It is identi- Englishman, Rumsey, organized experiments Above we have a view of the boat from the front, cal with that of the fish. On either side of the shattered by showing the location of the propeller and the gill boat are openings corresponding to the of the same kind, which were r-echanism. The whole arrangement works like a gills of a fish. the highly developed pessimism of the clay. pulsometer. 984 Science and Invention for March, 1928 Can Siamese Is Life for One

By JOSEPH H.

Fig. 1. Here is a photo- other; if one graph of the Hilton eats or drinks food which twins as they appear on does not agree with his constitution, the t h e vaudeville circuit. effect on the other is negligible. There is, Even though joined to- of course, some inconvenience, gether by nature, by an because if inseparable bond which one is too ill to remain out of bed, the other can only be severed in must lie down with the ill person; or if one event that one of the twin develops an infection, twins should happen to the infection may die before the other, they be carried to the other through the bond of do not look exactly alike. flesh (through the intermediary of the blood An X-ray photograph of vessels and capillaries), these twins would dis- which holds the two close that they both had bodies in the position of their birth. distinct pelvises, but that One cannot always be assured that even the connection which those twins joined together by a bond holds them linked to- of gether is a union of the flesh and with no bony junction whatever, bones at the lower part can be separated without danger to each of the spine, specifically other. For instance, there the sacrum and coccyx. are the Hindu Speedy surgical inter- Twins, Rodica and Doodica, who were vention in case of the joined in a fashion similar to the original sudden depart- ure from this life of one of the twins, is the only means Fig. 6. Whatever c a n of saving the happen in the animal other. No one kingdom can likewise can prognosti- occur in man. It is quite possible to have a two - cate the end headed human being. The results. photograph at the left shows a pig with three eyes, two mouths, two noses, and two tongues. THE name, Siamese Twins, is given to refer to twins like the Phil- practically every form of double - lipino Twins, again the answer growth in the human race, regardless is "Yes"; but when we apply of how the twins may be joined to- the term to the Hilton Twins, gether. The name dates back from the two the Blazek Sisters, or to the youths, Eng and Chang, who were born of Indianapolis Twins, the answer Chinese parents in Siam, in the year 1811. is emphatically "No." The lat- They traveled with circuses for many years, ter group cannot be separated and lived to the ripe old age of sixty-three. because of the eminent danger They popularized the term Siamese Twins, to either of the two parties. and now every congenitally joined twin is The only possibility of separa- popularly called a Siamese Twin, regardless tion is if one 'twin should die of whether the twins are joined back to before the other and the sur- back or side to side. geons were prepared to oper- In the original Siamese Twins, there was ate immediately. a band of flesh stretching from the end of Ordinarily, Siamese Twins one breast -bone to the same place on the are two distinct characters. If opposite twin. Otherwise the twins were one pricks himself with a nee- two distinct normal individuals. dle, it has no effect on the

Fig. 2. Dia- gram indicates an ovum d i s - Siamese Twins, and were divided by turbed so as an to separate operation in Paris, France, in February, the body 1902. Rodica survived the operation; her into two por- sister succumbed to tions. This tuberculosis. may or may PERCENTAGE not be the OF SIAMESE TWINS BORN cause of Before proceeding further, let us try to Siamese determine exactly what twins. takes place in the case of conjoined twins. There are many DIFFERENT STRUCTURE OF DOUBLE -TWINS other malformations and many different Having seen the reason for calling all types of monstrosities which develop, but their proportion is not very great. Mal- conjoined beings Siamese Twins, and ac- formations cepting the popular version of the term, we occur in from 1.55% to 2.83% births. The question as to the cause of must, therefore, ask the question-which these malformations Siamese Twins does one desire to separate? is still a disputed one, but it may be mentioned here that maternal If we are referring to the original, then the (mental) impressions answer is "Yes, they can be parted." If we as such a cause, can be definitely dismissed as a relic of those

Fig. 3. The Fig. 5. Twins diagram here Joined at the illustrates sacrum and an X- ray coccyx a r e view of the not unusual. Phillipino The diagram twins w h o indicates show no such a union. bony connec- Separation tion. They quite impos- could be Fig. 4. Two cherries, side by side, finally become sible. separated. but one. This is a possible cause of Siamese births. Second row shows cherry mutilated by outside injury; third indicates growth of a birthmark. Science and Invention for March, 1928 985 Twins Be Separated? Possible Without the Other?

KRAUS

Fig. 7. An X-ray photo- Fig. 9. This graph of the diagramme d Blazek X-ray gives a twins which view of the shows them Indianapolis joined to- twins. Here gether in the the bones are manner here fused in the indicated, manner indi- with the ilia cated. It is fused. They impossible to cannot be separate separated. these twins.

and to the lungs, but this two -headed pig days when fantastic grounds were looked has only three eyes and the center eye does upon as being explanatory of all things not seem to be double. In the case of the unusual. snake and also in the case of the human monstrosity, both heads are complete. The HOW TWIN GROWTHS FORM calf, on the other hand, can eat with either It has been thought since earliest times mouth, but cannot use both mouths at the that double or multiple monsters are the same time. Unfortunately, this animal is result of fusion of what were primarily two blind in two eyes, but can see with the or more individual embryos. This view is other two. explained in Fig. 4, showing the two cherries Conversely, instead of having two or more Fig. 8. It is unusual to ilnd a two -headed hanging from the twig of a tree. In the human child with two complete spinal col- heads on one or more spinal columns, at- first view, and when the cherries are quite umns and but one pelvis, yet the diagrammed tached to but one pelvis and with one com- small, they are seen as distinctly separate X-ray photo shows such an existence. plete set of extremities, we can have a single - fruits. As they grow, they touch each other, headed, double -bodied human being. An ex- and from this point on, they become joined, column. We find several examples of this ample of this is illustrated in the diagram on producing a cherry with two pits and two on the accompanying pages. We see in Fig. 6 the third page, Fig. 13, where there are two stems, yet as far as the fruit is concerned, a two -headed pig, a constitute merely one single cherry. The two -headed snake, in same course may take place in the kingdom Fig. 11, and a two - of the mammals in which, of course, man is headed cal f, in Fig. 16.

Fig. 10. The photograph at the right shows Mary and Margaret Gibb, very popular Siamese twins, and their mother in the background. Mrs. Gibb is probably the only American mother to survive the birth of Siamese twins. It is very questionable if these sisters can be separated without danger to each other.

Fig. 11. The two -headed snake here shown differs from the two - headed baby, diagonally above, only by the fact that the one is human and has a double spinal column, while the other has only a double head. included. On the other hand, the twins may We can see a diagram be what is known as unioval ; that is, they tracing from an X-ray are produced from one ovum. While com- photograph of a two - monly they become two separate entities and headed human infant, two individual personalities ; due to some which is also double arrest in development, or due to some dis- for the entire length turbance resulting in an abnormality of posi- of the spinal column, tion, the two bodies may be fused. Thus but which has but one there is on record a case in which there were pair of arms and two spinal columns, distinct to the pelvis ; which has one pair of one column sustained two heads, whereas legs, in Fig._ 8. Ana- the other supported one head, giving us a tomically, me find that typical three -headed monster. Triple mon- some organs are dou- sters are quite rare. bled in this infant. It is interesting to TWO -HEADED PIGS AND SNAKES note that in the case Then there are those cases of double - of the pig, there are headed monsters, some of which are double two complete mouths only, insofar as the head and neck is con- and noses, each with cerned; others which are double for a its own tubal connec- greater or a lesser portion of the spinal tion to the stomach Science and Invention for March, 1928 Siamese Twins-Their Separation

Fig. 12. Luido and Simplico Godino, Siamese twins from the Island of Samar, here pictured entering a car they are about to learn to drive. complete individual bodies joined to but one coccyx (end of spinal column), as illustrated distorted head, and also joined at the sternum in Fig. 15. The lower portion of the intes- or breast -bone. tines join together in one common duct. In this particular discussion we are pri- While it is quite possible to separate them, marily concerned with duplicities and triplic it could only be done in event of the acci- ities rather than with those monstrosities of dental demise of one of the sisters. What a parasitic nature, wherein a more or less the outcome of such surgical interference perfectly formed body is attached to a well - would be, cannot be even hinted at. formed individual, but has no separate ex- Barring a possible surgical shock, the istence and receives its nourishment wholly Phillipino Twins, who are joined together as from the well -formed body. indicated in the X-ray view in Fig. 3, could It is quite obvious by what has just been be parted from each other. said that it would be impossible to separate A very unusual case is presented by the one of the heads from a double -headed indi- Indianapolis Twins, indicated in Fig. 9. vidual. It also would be impossible to divide Here the inferior portions of the pelvis are the double head of either the calf or the pig fused with each other, so that one pair of or to remove one of the bodies in the legs of one twin lie beside the body of the double -bodied animal indicated in Fig. 13. other. It is extremely doubtful that either could survive, if surgical intervention was There are limits to modern surgery. Fig. 13. It is possible to have a single -headed, Again we return to the question-which double -bodied human being, just as it is pos- necessary. A similar state exists in the be separated? The answer is, sible to have a double -bodied single -headed case of the Blazek Twins, indicated in Fig. twins can animal, as the diagrammed X-ray shows. primarily, those in which there is no bony 7, where they are joined together by fusion between the iliac (hip bone) bones. connection and, secondly, those where there is absolutely the life of danger that the separation is a bony connection, but where of the healthy one. one or the other of the twins is in such necessary for the welfare One must remember, though, that practically every freak condition found in animals may find a counterpart in man. Those very pretty and popular sisters known as the Hilton Twins are joined together at the sacrum and

14. The old circus crowds probably remember the Fig. Fig. 15. An X-ray diagram of the con- two -headed, double -bodied calf which was exhibited by twins. P. T. Barnum. There is no record that an X-ray of this necting link between the Hilton calf had ever been taken, nor is there any indication as Fig 16 (right). A two -headed calf to whether the calf was not a built-up freak. Neverthe- which can eat with either mouth but less, it is quite possible to have an animal or a human not with both at the same time. It has being born in the form depicted in the above photo. four eyes, two of which are blind. Science and Invention for March, 1928 't7 Fish Harvester Modern Scientific Method of Wholesale Fishing

The illustration shows the proposed arrangement of equipment to be employed in a new method of wholesale fishing. It will be seen that there is nothing intricate about the construction of the apparatus, for it works upon the well-known principle that ':sh are attracted by light. It is estimated that a ship constructed as shown here will cost about $45,000.00.

New Flomecralt THIS fish harvester here illustrated and The illustrations at the described will remove the last trace of left show the type of small castings in grey romance connected with the ancient art Of iron, which may be ob- fishing. This revolutionary fishing apparatus tained without the usual is essentially the invention of Elwood sharp edges, which gives a desirable appearance Blecker. of antiquity. Fig. 1 is On the way to the fishing grounds, the a book -end, 2 is a door chain and windlass hold the fishing equip- stop, 3 shows a pair of andirons, 4 is an iron ment above the surface of the water. When mail box and 5 is a sun a suitable site has been reached, the ship t-- E dial. is anchored. or if the tide is not sufficiently strong, the ship is moved slowly forward The illustration below wt4Mwl rsuäÌl:!re.4t.. j,...a.e shows a girl engaged in with the metal net just below the surface. the pleasant work of The fish in their attempts to get near the decorating one of the light, soon find themselves crowded into the Mit.%.';. small castings which are supplied in many forms. conveyors by the forward motion of the Illustration courtesy of boat or action of the tide and the guiding .Ilhauy Foundry Co. effect of the metal mesh. After leaving the conveyor at the deck, they simply fall into the hold; and the dangerous and disagree- able work of hauling and emptying the old- fashioned nets is eliminated. The rate at which fish are being caught is known at all times by simply watching the conveyors THE castings should be decorated with and no time is lost by dragging nets through ordinary oil colors sold in tubes., or with fishing grounds which contain little or no the various shades of bronze, enamel or fish. liquid sealing wax. A coating of white paint This machine will be especially useful for is applied and allowed to dry before the catching fish which move in schools, at or decorating medium is applied. The surface near the surface, such as the herring. The of the castings is smooth and hard, sharp use of this latest type of machinery for the lines are omitted to imitate the antique. wholesale harvesting of fish must be accom- Castings may be obtained in the form of panied by corresponding intelligent activi- andirons, door knockers, candlesticks, candle ties to prevent the depletion of the present sconces, hook -ends, door stops, and many abundant supply of fish. other decorative forms. -lila.<. courtesy of Scientific Fishing Association. 988 Science and Invention for March, 1928 Scientific

A Photographic Picturizatiou

-1t is almost impossible to keep up with ence. This is truly a scientific age, and directly or indirectly, will he of lasting can portray but a made in many

TUG -O -WAR BETWEEN AIRPLANE AND AUTO-The photo shows a 1915 Ford in an engagement with a Waco plane, powered with a 220 -horsepower motor. The Ford develops but 22 horsepower. The latter machine gained an advantage over the plane in the early part of the contest, but when the Wright Whirlwind motor was opened wide, the little car was overcome. The contest tools place at Chandler Field, near Atlanta, Georgia.

¡ SNOW PLOW-One of the hundreds of tractor snow plows employed in Switz- erland to clear the roads during winter months. They are used every day during winter season.

MANICURING MA- CHINE - Miss Mary Chandler demonstrating how the new nickel -in - the -slot manicuring device is manipulated. Two fingers are placed on the polishing surface at the same time.

CATERPILLAR TRACTOR BARROW- The photograph shows the application of the caterpillar tractor idea to a wheel barrow. It is the inventor's claim, and it seems to be borne out in practice, that the wheel barrow designed as the photograph indicates, is capable of being operated more easily over very rough or rocky ground. An ordinary wheel -barrow stalls in front of larger obstacles.

IarlÉ" 14 ea; u ® p uutliti

AUTOMATIC VENDING MACHINES-The above photograph shows the automatic merchandising devices recently placed into service in a United Cigar Store in New York City, where the customer can secure his package of cigarettes without waiting in line. Three machines make change, and then one drops the proper currency into the slot of the machine which distributes the cigarettes or cigars designated on the front of the panel. YOUR PHOTO IN LINDBERGH PLANE. The Lindbergh influence has certainly had its effect on the enterprising photographers in Mexico City. Sensing to Mexico might bring, several the business possibility that Lindbergh's visit as enterprising photographers rigged up contrivances to enable anybody to pose The photograph at the right shows the an aviator In the "Spirit of St. Louis." side and view of the canvas. Place your fingers over the spectators on either observe the effect produced by the finished photo. Science and Invention for March, 1928 989 Progress of Modern Scientific Ads aiices the rapid strides taken in the field of sci - the knowledge which we daily obtain, benefit to the race. On these pages we few of the advances different fields.

BREATH - TAKIIG LANDING- With ins parachute tangled :i the plane, Miss Jest West vas dragged ove? the ground as the aL plane tarried to a stop.

SPIRAL - VANED VESSEL. This type of construction has been used on land, on snow, and now we see it in the water, traveling at a speed of 12 miles per hour.

BANK VAULT OXYGEN TANK-It is not unusual for a teller at a bank to find himself locked up in the bank vault with little or no possibility of escape.. This photograph shows the new system for supplying life-giving oxygen and was taken at the conclusion of a successful test.-W. L Gaston.

THE SWORD 01' LIGHT-Interesting photographic records of the recent eclipse of the moon were made in Berlin with ordinary equipment. The photograph above shows the unique two-blade sword of light in the heavens obtained by a continuous exposure on a photographic plate. The picturization shows how the light of the moon diminished as the shadow 01 the earth crept across its face and its return again to normalcy from the point of totality.

THE DAWN AND ITS LANDING GEAR-The photograph shows the ill-fated Dawn shortly before its last take-off. This was considered by airplane designers to be the last word in safety. The insert shows the way the wheels fold into the body of the plane when not in use. CAMERA + PAINTING = AVIATOR-The photograph here shows an "on location" scene. The picture of the "Spirit of St. Louis" is painted on the canvas, and the "terra firma" aviator pokes his head up through the hole in the canvas prop. Note photographer surrounded by spectators and compare this picture with the one on opposite page. Science and Invention for March, 1928 Eliminating Fatal "Tail Spin" "Tail Spins" Have Accounted for the Deaths. of Many Famous Aviators-New Device Eliminates Them By C. A. OLDROYD AERONAUTICAL ENGINEER (English Correspondent) fully adjust the various factors to get the (Excerpt from letter written to author by AUXILIARY Handley Page Company.) HINGED best possible results with a given wing PLANES THE object of the device is to provide profile. complete lateral stability when stalled. As we increase the angle of inclination The main characteristics of an aircraft when of our airplane wing, the air pressure at a automatic slots to given speed does not increase continually, stalled, and fitted with point "X" the extremities of the wing, are that the but only up to a certain critical center portion of the wing is stalled, but by (Fig. 2) ; at a still greater inclination, the virtue of the slot, the wing tips are not air pressure drops suddenly. automatic lateral If an airplane rears up to such an angle, stalled, which thus provides support stability. From the pilot's point of view, there will not be sufficient "lift" to when flying in a stalled state it appears as if the machine; it will be "stalled," as the pilot are attached to the wing tips; terms it. It loses flying speed, and tends to "sky -hooks" one wing tip nearing because whatever happens, the nose of the roll over to one side, and never the the ground, the other pointing upwards- machine always drops first OF AUXILIARY in aircraft which are not FOR CROSS-SECTION in other words, the machine drifts into a wing tips, whereas to counteract on fitted with the automatic slot, a wing invari- PLANES SEE FIGURES 8 TO /0 spin, which is most difficult the part of the pilot. ably drops on the aircraft being stalled, and Above we have a view of a plant equipped notinfrequently is followed by an incipient with the new wing slots which eliminate the SMOKE SHOWS HOW WING ACTS considerable deadly tail spin. Fig. 7. spin, a maneuver which requires this sudden loss of lift height and prompt action on the part of the Experimentally, can be shown in the wind tunnel (Fig. 3) ; pilot to counteract. With our invention the The answer is this : Up to the present here a wing model is suspended at the angle INCIPIENT SPIN IS ENTIRELY ELIMINATED. We time, airplanes have not proved sufficiently saying that stable for general use. If you have ever under test. Smoke threads are injected at have no hesitation, therefore, in threads with our device are different points; these aircraft fitted appear as dark lines in the photo, 85 cent safer than those not per and with their aid we can trace so fitted. the air flow and visualize its A special feature of this device speed of the effects. is that the maximum The wing section shown in aircraft is in no way reduced, as photo Fig. 3 is set at a steep at high speeds the slot is hinged condition. In- the plane, and forms a angle, a stalling back into stead of an even flow of air past natural leading edge. the underside and upper surface much AVIATION is one of the of the wing, we get a very world's youngest indus- disturbed flow. Eddies appear tries, and slowly but in the regions marked, and as surely its many dangers they do not help to support the they only waste power. and difficulties are being over- machine, to the ceaseless ef- Mr. Handley Page, a well- come, thanks known English airplane designer forts on the part of aeronautical the designers and research workers. and constructor, discovered flying called "slotted" wing, which has a nar- Up to the present, near edge of for a great deal of skill, and for row slot the front capable the wing. Applied to the case men of quick perception, from the of acting instantly in an emer- under discussion, we see photo, Fig. 4, how the current of gency. re- is it that flying is still air passing through this slot "How flow of air such a tricky business ?" the read- establishes an orderly past the wing. The greater part may ask. "We have strong a Handley Page plane equipped with an er The above photo shows eddies and the airplanes, high - power engines automatic wing slot, which makes a plane fitted with this device of the disappears, 85 safer than an ordinary one. more in a normal capable of running hundreds of per cent wing lifts once hours on end, and under full fashion. load, too. And yet-flying does not appear amused yourself with flying small glider THE HANDLEY PAGE WING SLOT to become any safer." models cut from stiff paper, to resemble more or less an airplane in appearance, you For some years past, Mr. Handley Page will recall how difficult it is to get such a (Continued on page 1028) (i) NORMAL FLYING ANGLE model to fly straight and without "wobbling" for even a short distance. REGIO FORCES ACTING ON PLANES WING Briefly, the working principle of an air- SECTION EDGE Fig 8 \LEADING plane may be explained as follows: (Fig. 1) The rapidly rotating propeller pulls the air- SMOKE ON OF STALLING -(THREADS (ii) POINT plane through the air ; the machine is supported aloft by the air pressure on the wing surface. -ANGLE { The various forces acting on the wing are OF 1. At a certain point, called shown in Fig. INCLINATION the "center of pressure," the total air pressure may be assumed to be concentrated, as SLOT far as its effect is concerned. `-)SMOKE This total air pressure, PT, acts at right THREADS angles to the wing section. Resolving the IN AIR vertical and horizontal forces, we obtain Pv, the vertical lifting forces, and the drag, CURRENT PD, the resistance the wing offers to progress through the air. AUXILIARY PLANE In Fig. 1, the wing is shown inclined at SLOT OPEN Fig (STABILIZER) SHOWN a certain angle to the horizontal; the greater IN become Pv and BLACK this angle, the greater also threads, injected in of forces is linked to- Smoke a wind tunnel, wing PD. This family provided means for studying the air flow The action of the auxiliary planes or must care - using the slotted slots are illustrated in the above drawing. gether, and the airplane designer when wing, as shown above. Science and Invention for March, 1928 001

Before a generator is installed, it is thoroughly tested out on the test Here we have a view of a group of students acquiring skill on bench block. In modern automobile schools, the students learn both the mechani- lathes, and at the same time learning how to true up commutators, arma- cal and electrical features of the game. Even theory is not omitted. tures, and how to test them electrically. what Makes an Automotive Mechanic? The Great Question of To -day ---Auto School o r Garage Apprenticeship ?-Is Here Discussed By HENRY TOWNSEND

AST year the number of motor This brings to mind a very interesting From the writer's experience and that of vehicles registered in this country problem which daily confronts the parents many of those engaged in the automotive showed that over twenty-two million of our bright young men, who are about to industry, it would seem that on the average were in actual use; or in other leave school and learn a trade or profession. the young man graduating as a certified words, practically every family was sup- Shall they endeavor to place their son in a student mechanic from a modern trade plied with one of these modern vehicles of local garage, where he may serve three to school, at the end of three to six months as transportation, either for pleasure or busi- four years in order to become a finished previously outlined, can start at the same ness. One of the old adages in the auto- mechanic; or should they send him to an wages per week as his brother mechanic, mobile field has been that "it costs more to up-to-date and properly equipped automotive who has spent three years and possibly much keep the average motor car in repair-than trade school. longer, working eight to nine hours a day it does to build it." Many of us without a "Well, that is a very difficult question," in a public garage as an apprentice. Then doubt have done some tall cussing when the you will answer, no doubt. What is the com- think of the rapid promotions enjoyed by monthly garage bill arrived. parison in wages and the time required for the ambitious graduates of the high grade As was recently pointed out by the Na- a person to learn the automotive trade thor- trade school. tional Automobile Chamber of Commerce, oughly, in the public garage as an appren- The writer wishes to stress a point or there is a veritable army of over three mil- tice ; as compared to taking one of the com- two in a purely unbiased way, with regard lion people employed in the automotive in- bination, practical work-theory automotive to the salient features of the modern auto- dustry. A great part of this vast army is courses in a first-class school. The answer motive trade school, which teaches both employed in giving service to the motoring is that considering three years as the mini- practice and theory to their students, in public through eighty-six thousand public mum time in which an automotive mechanic comparison to the training received by the garages spread across the country in town can be classed as a skilled mechanic, the average apprentice in a garage, whether the and city. student taking a course at an automotive latter is located in a city or small town. Some of the excessive automotive repair school can be taught the equivalent amount It cannot be gainsaid that the average hills that you and I have received from time of practice, and also the very necessary garage mechanic is frequently found woe- to time are, frankly, due to the fact that theory and technical part ; in the remarkably fully weak on the theory of the gasoline this great industry has grown so rapidly that short period of three months, working six engine, not to mention the ignition and light- a suitable number of properly trained auto- hours a day ; in six months time if he only ing system of automobiles. Unless the motive mechanics could not be supplied. works three hours a day in the trade school. (Continued on page 1026)

This photograph shows a few of the mechanical departments of a modern The proper amount of heat is very important. Overheating spoils metal, automobile trade school, where the various types of chassis are overhauled. hence these students are being instructed in the proper amount of heat Observe the very thorough equipment. to use in straightening an auto frame. 9), ) Science and Invention for March, 192ó Strange Hobbies and Crafts of A National Scientist Makes Experimental Locomotives, a a Lumber Dealer Carves Wood While a Famous Football

By GEORGE H. DACY

The hobbies of this college professor, L. J. Ingersoll, are indicated in the photograph above, which shows some of the toys he makes during spare hours.

the time capitalists" is an ap- as most of the locomotive's are run by elec- leaves the tunnel at the opposite end, C C propriate name for a group of trical power. This rail consists of a copper lights are switched off. The rails are sanded devote their wire which is soldered to wood screws. to keep the locomotive wheels from slipping. friends of mine who runs by leisure to the pastimes of riding \Vhen Mr. Boutell wishes to start one The above type of locomotive designing, toy mak- of his model trains, he turns a control switch means of tiny electric motors concealed in strange hobbies-model Mr. Boutell has harnessed the ing, wood carving and making golf clubs. which sets the engine in motion. It backs the tenders. become so expert at into a train of passenger coaches until they same electrical current which illuminates These gentlemen have run the locomotives and their recreative specialties that they could are all coupled together. Then the train his home to also from their sidelines rolls down the track, up -grade and down, rolling stock. The turntable is operated by earn attractive incomes A ferry boat which links if until finally, it comes to a tunnel through thread controls. necessary. is also run by thread Hugh Boutell, a prominent mechanical the hills. The electric lights in the cars into the railroad system Uncle Sam, spends and the engine headlight flash up . just as controls. The boat is provided with electric engineer, who works for while the pas- evenings at home where he designs and the train enters the tunnel. \Vhen the train lights which burn brightly his is motion. makes tiny models of railroad locomotives. senger craft in are accurate in every The accompanying pictures will give a These midget engines description can, of respect and can be operated under their "Pop" War- better idea, than a what ner, the fa- the railroading exhibit in the Boutell attic own power. mous football looks like. You will notice that the system coach, tells ENGINEER PLAYS WITH MODEL TRAINS all about seems to be located in a region of hills and home in Wash- the features valleys. This effect is secured by small can- In the attic of the Boutell of his home- is of the most extraor-, vas scenes which the scientist has painted ington, D. C., one made golf borders railroad systems in the world. The clubs. Insert and placed along the of the track. dinary The scenes and form a garret floor is covered with a network of shows the dovetail together tracks. Diminutive locomotives improved picture of a rolling landscape. railroad club. Boutell is in haul Liliputian freight and passenger trains Mr. greatly interested the here, there and everywhere. A railroad history of American railroading. On his in miniature has even been curious attic system, he-has tested out home- junction town made cars and locomotives similar to the devised as a part of this astonishing dis- power commercial equipment in use at different play. Clever models of railroad shops, the plants, turntables, houses, schools, stores and periods during development of the complete the industrial picture. United States. The railroading exhibit al- churches though a pastime hobby has enabled him to The exhibit is one of the best and most com- kind ever assembled. gain familiarity with all the difficult prob- plete of its lems c,f American railroading during the This engineering expert during the last made more than 40 little different stages of growth. Mr. Boutell seven years has has devoted all his spare time for seven years locomotives, all of which run and are accu- The engines are made to this unusual recreation. He told me that rate in every detail. it took more than six months of his idle of tin, iron and steel. One of them runs steam being generated hours to put together the railroad village and by steam power, the system which you see in the illustrations. ill the tiny boiler of this "Tom Thumb" locomotive. The cars are made of card- PROFESSOR MAKES TOYS AS A HOBBY as are also the buildings, board and plywood L. J. Ingersoll, a professor at one of the houses and shops. the railroad track is a leading state universities of the Middle West In every aspect, makes toys as hobby, in fact, he dedicates perfect copy of a commercial line. The a wooden crossties which the week before Christmas to the novel brass rails rest upon occupation of making playthings for his are anchored securely in ballast of crushed rock and cinders. There is also a third rail four children. The collection of toys which Science and Invention for March, 1928 993 Successful Men College Professor Plays Toymaker, Coach Makes Golf Clubs

this professor has made during the last eight years is better than any which Santa Claus ever distributed. Many of these valuable playthings took several weeks of painstaking and skilful work. Professor Ingersoll usually devotes his idle hours throughout the entire year to his extraordinary pastime. The week before Yuletide season, he completes and perfects all his homespun carpentry. The Ingersoll toys are made from white pine, yellow pine, oak, poplar and cedar. First of all the professor draws accurate designs and plans of the toys which he purposes to manufacture for that particular season. His designs are always original.

In the attic of Mr. Boutell's home, we find every mechanical appliance used in modern railroading. Highway gates are raised and lowered automatically, signals operate, and the trains move around the tracks as if controlled by individual operators.

A merry-go-round is one of the finest blocks are twice as long as they are thick and of the Ingersoll mechanical toys. It is twice as long as they are wide. They can be worth at least $150 and is probably the finest used as geometrical blocks in all sorts of con- specimen of it kind ever produced in struction work by. the juvenile builders. America. The amateur toy -maker remod- Altogether, the Ingersoll toys are worth elled a small engine so that it furnishes more than $1500 and represent the spare mechanical engineer, power to operate the merry-go-round which time industry of a fond lather. Mr. Boutell, a prominent The arrangement makes use of his spare time by designing and works on a bicycle gear. WOOD CARVING, A SPARE -TIME JOY building midget locomotives that run. Photo is such that the horses, cars and seats on shows a few of his forty models. the apparatus rock to and fro and whirl L. J. Scheve is a prominent St. Louis lum- about as the main platform turns. A toy ber dealer who by home practice, during his He aims to make toys such as are never piano plays as the device rotates, being ac- leisure time, has developed into one of Amer- found in commercial shops and stores. He tuated by the uniform motion of the merry- ica's most expert wood carvers. Fifteen makes the playthings strong and durable. go-round. It required more than 200 hours years ago, being interested in amateur wood- Some of them have been used for four or of work for the professor to build this working, Mr. Scheve built a large work five years by a quartet of robust, romping mechanical toy. bench in his basement and began to master children and they are still serviceable. An accurate model of an ocean liner is (Continued on page 1029)

Here are but a few of the What is more natural than samples of work done by to have -a prominent lum- Mr. Scheve in the base- ber dealer use his own ment shop in bis home. lumber when building His tabouret, shown at the things. The photographs left, is worth approxi- here show Mr. Scheve at mately $150.00-not so bad his work -bench, where he for an amateur wood- spends many hours carving. carver. And below a hand -carved tabouret he has built.

another masterpiece in the Ingersoll collection. It has been made to scale and is a perfect facsimile of one of the mammoth salt sea greyhounds. A sailboat on the model of one of America's cup defenders is another remarkable nautical toy. A locomotive, tender, and three cars made of wood compose an almost in- destructible railroad train, which has withstood five years of trying service. A toy house modelled after a Swiss chalet is another wonderful example of amateur carpentry skill. The front of the house is removable. The interior is divided into rooms, all of which are completely furnished and lighted by a tiny electric plant. The sitting room is even equipped with a cuckoo clock which works automatically. A set of building blocks made of cedar of Lebanon is another outstanding feature of the homemade toys. These 994 Science and Invention for March, 1928 Largest Reflecting Telescope in Europe

(A Ocular piece mirror ocular mirror

piañc-, mirror convex mirror plane mirror Newtonian Arrangement Cassegrainian Arrangement smmur- Above, the upper end of the fifty -inch The Newtonian and Cassegrainian arrange- The telescope and observing platform are reflector. ments are compared above. shown in the photo.

THE recently erected reflector at the ob- and side levers, the -object of which is to mounted in the revolving portion of the servatory in Neubabelsberg, in Germany, preserve the shape of the mirror in differ- dome. The observing carriage moves on is the largest of its kind in Europe. The ent positions of the tube. After the erection rails on the platform. A system of gears diameter of the large concave mirror is fifty of the reflector was completed, the observing controls the movements of the observing inches, the focal length 27.5 feet. The mir- platform for the Newtonian focus was ad- , carriage by motor or by hand. Hubert ror is mounted on a system of cushion levers justed. This platform is carried on rails Slouka. Air Currents Now Photographed

HOT AIR CURRENTS /ARE VISIBLE AND NEW TEST TRUCK OK WHEELS CAMERA PHOTOGRAPHS AIR CURRENT PATHS r Ja MILE TUNNEL WITH AROUND AERO- TRACKS E FOIL SURFACE

An exceptionally high- speed motion picture The photo at the left camera, adaptable to shows the (hot) air the photography of flow on a model of a high - speed (hot) a i r Thomas Moore airplane flow was recently fuselage which was demonstrated; is is ca- photographed in a wind pable of taking 20,000 tunnel. Shown above is pictures a second. a wind tunnel which is Above is shown the one and one-half miles paths taken by (hot) long and runs in a air currents passing straight line. As the over a wing. With this air in the tunnel is new device it is pos- very still and the sible to study the air tracks are perfectly flow over the body of a smooth, it is expected plane. The camera was to be very efficient. first demonstrated here This tunnel has been at the Daniel Guggen- built at the Toyko heim School of Aero- Imperial University nautics at N. Y. Uni- through the aid of the versity. Photo courtesy "Aviation' Japanese government. Science and Invention for March, 1928 995 New Apparatus for Retinal Examination THE old observer looks apparatus through t h e which was unillumi- used for eye nated half of examina- the pupil into tion was found the interior of to give incor- the eye under rect results examina- due to the re- .,91,18E ET? ftAnE:`1lA,tC: tion and sees flected light the retina. The from the cor- Above we have a drawing which shows the con- diagram nea of the eye. struction of the new device for examining eyes. shows how this is done. Recent- of ly, Prof. The beam Thorner of light emitted Germany suc- by the lamp, ceeded in con- goes through structing a re- the condenser, flecting instru- and after re- ment which flection on the avoids this mirror, gives trouble, an image of whether d u e the source of to the reflec- The above photo shows the eye examiner light on a sec- complete with all other apparatus installed o n d smaller tion by the case. At the left the cornea or to in its carrying mirror which device may be seen in use. Illumination on the lens of the is given by a small lamp which draws its is exactly instrument. In current from a pocket flashlight battery. the line of the Prof. Thorner is the inventor of this screened por- the new appli- device. ance there is tion. The rays no lens. In its then go from place there are the square mirrors which illuminate the retina of the entire area of the pupil of the eye; in the plane mirror, to a convex mirror, and thence eye. These mirrors carry the image to the new instrument it only goes through one- to one-half of the pupil of the patient's eye eye of the observer. Hitherto the light for half. One-half is screened so that no dis- and light up the retina. The rays reflected illuminating the retina went through the turbance due to light can occur. The (Continued on page 1029) World's Largest Gas Tank

Statue of Liberty Gas Tank at Harrison 7 Leviathans needed to equal New Jersey PAtFi Gas Tank capacity -_`-9iW 2 f' 1M`1I eYiKrS-VW WWI 72 Tons of -Tar 702 cuft. Liquid Ammonia .]_s ,2 e. .-. Cars Tons 30 (40 capacity) x/200 Tons 'Qt. -Coal 35 Cars required to remove Coke required to bring coa/ 700 Tons of Coke The largest gas tank in the world has been constructed at Harrison, New Thirty freight cars of 40 tons capacity each would be required to 'bring Jersey by the Public Service Electric and Gas Co. This huge tank is the coal used for making enough gas to fill the tank. Thirty-five cars capable of containing 15,009,300 cubic feet of gas. The tank itself is 345 of the same carrying capacity would be required to move the 700 tons feet high and 240 feet in diameter, and is 40 feet higher than the Statue of coke which would be obtained as a by-product, after burning the of Liberty. Seven Leviathans each 950 feet long would be required to coal. Further by-products of the combustion of the 1,200 tons of coal equal the gas tank capacity. In order to fill this tank to its capacity, would be 72 tons of tar, and 702 cubic feet of liquid ammonia, besides it would necessitate the burning of 1,200 tons of coal. thn 700 tons of coke mentioned above. Courtesy of Technik Fiir Aile. Science and Invention for March, 1928 The Month's Scientific News Illustrated By GEORGE WALL

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On a truck farm in Virginia, irrigation is car- ft,AGHUTE Mr. A. O. H. Perry, of Hasbrouck Heights, N. J., ried out by means of overhead pipes. A large ' part of the farm is wired for electric lights, recently released a toy balloon with a card at- which are used to combat tomato worm moths. tached to it which bore his name and address. The moth traps are placed about ten feet above This balloon travelled to Maracaibo, Venezuela, the ground and six inches under the electric where it was picked up by Antonio Quintero, Who light, attached to the pipes. immediately notified Mr. Perry.

CAMERA

NF LATED GOLLAPS BLE RUBEER RAFT

+ I i Corp. Richard L. Huffman of the Marine WALE Corps inflated a collapsible rubber raft while STICK. falling 3,000 feet from an airplane to the Po- tomac River. When the raft was inflated he dropped it, released himself from his parachute when reaching the water and climbed aboard, rowing to safety.

3 Asserting his right to cross the street in Explosions are symmetrical and are not an safety, a pedestrian appeared in Southampton, erratic splash of fire as they seem to be. England, with a miniature but noisy motor Tests made at the National Bureau of Stand- horn attached to his walking stick. He sounded ards with soap bubbles filled with explosive warning blasts to automobilists when he was gases and fired by a spark, permitted extra- about to cross the street. ordinary photographic records to be made of "blasts."

The Interborough Rapid Transit system of New York City keeps track switches clear of ice and snow with a unique system of electric snow welt- ers. The heating unit is placed under the track switch and is connected to the third rail. About ILLUMIN- twelve heating units are applied to each switch. ATED The thermostat turns on the current automatically BATON whenever the temperature falls very low.

In Kansas City there has been built a bouse said to be tornado - proof. A storm -proof bedroom i has been built in the basement, the concrete walls and ceiling are eight inches thick, reinforced with iron bars. A ten - foot passage leads to a "tornado cellar." The owner intends to take pick and shovel with him, so that he can dig his way to the surface.

t--aeCE .

The majestic white baton of the Parisian traffic gendarme will now be replaced by one having electric lights. A French inventor has devised an illuminated baton which was tested and found practical by the police. This baton has two electric lights in a notch at the top; one light is red and the other white. Electric wires run through the center of the club to a small battery strapped on the officers' belt. The club is the invention of M. Legonas. Science and Invention for March, 1928 997

Above we see one of the completed model farms which has been built to exact scale. Notice the exactness and detail obtained. Miniature Cities ---How Built By LEE BLACK The Man Who Builds Them Increasing Demand for Realism in Replicas for Exhibitional Display-How to Build and Sell Them N insistent of the newly -awakened interest in replica - sional values, is demand for craft. rapidly supplant- the minia- The art may be classified roughly into two ing the conven- ture mod- general divisions-utility and exploitation. tional poster. eller's art is rap- In the former the model serves the purposes The miniature idly invading all of technical observation, research and model is the out- crafts which in- experiment; in the latter advertising, ideali- growth of this volve an intelli- zation, and attention -compelling composition. trend in the di- Above -Moulding a mountain of in- and color presenting pic- rection of real- Using comb to make gent form The art printing furrows. out of clay. dustry. This fas- torial subjects in flat values no longer satisfy istic advertising cinating knowl- the business man and ultra - preci- edge and application of all of the graphic who demands sion in the fields of utility and business. arts, was once confined almost entirely to more and more In either case its mission is to convey a the problems of architectural and engineer- realism in telling truthful and accurate story of an existent ing development. his story to the achievement or of a proposed ideal. And as The scale model, as it is known to archi- consumer -public ; such it expresses a satisfying fidelity which tects, engineers, shipbuilders and scientists, and it will have most certainly cannot he surpassed by any is of necessity a thing of machined precision been observed by other known medium. Its use by moving rather than ethical beauty of line and com- the reader that picture producers is well known and to the position ; and the latter enters the equation the so-called "cut- movies can be ascribed much of its present only when all of the requisites of the former o u t' ' revealing development. have been faithfully executed. depth a n d per- Tile advance of the scale model into the spective, and cre- PRICES PAID FOR MODELS realms of business has been subtle but steady. ating more or Tile prices paid for good models range Sweeping changes which have revolutionized less, the illusion Above - Spraying paint on advertising art over the past decade are hack of dimen- the houses. (Continued 011 pate 1030) 998 Science and Invention for March, 1928 Visiting Other Planets French Scientist Presents Picture of Scenery on Other Planets Than Ours By JAMES NEVIN MILLER something like the condition on earth at 1111111111M11111/11111111 11111/1 night. In this peculiar lunar day -time the stars do not twinkle. Yet a human voyager could At the left we have a see every detail of the landscape, near and conception of the varia- far as his eye could reach, with the same tion in the apparent size dry and constant sharpness. Because of of the sun as seen from the lack of air there would not be the slight- the various planets of est softening of the view; a remarkable the solar system. The contrast to the condition on earth, where sun, as it appears to the the different distances merge harmoniously inhabitants of the earth, in blending vapors. Here our atmosphere is shown in the center. presents a serious obstacle to really good The sun appears largest contemplation of the heavens, for it obstructs from Mercury and the greatly the light coming from the stars, smallest on the planet troubles their images and even limits their Neptune. visibility. In a sense it is a real veil placed before our eyes-a veil which is non- existent on the moon where the heavens

111,,,1111,,,,,11111111,1111,11111111111,1111111111/1w1111,,,11m shine in striking majesty.

be see their whole WONDERFUL VIEW OF HEAVENS IF human beings could voyage throughout traveller would unable to FROM MOON the great solar system what kind of extent at a single glance. "It would be scenery would they discover? Trans- necessary to turn around in order to see Fortunate indeed, therefore, would be the planted in the twinkling of an eye to their circular walls which would appear like lot of the astronomer -visitor to the moon. the various neighboring worlds, the moon a long chain of more or less irregular for- The wonderful richness of the picture would and the other mysterious planets, what won- mations. For some of them, were an earthly provide a facility for observation without drous and strange things might they find? visitor at their center, their ramparts would parallel here on earth. Color schemes would These imagination -holding considerations be so far distant as to be invisible, far put to shame our most magnificent offerings, are discussed by the celebrated French as- below our horizon." so unique and striking would they be. The tronomer, Lucien Rudaux, in a report to the "We must further remember that on the familiar beauties connected with the rising Smithsonian Institution, even more inter- moon, because of the greater curvature of and setting of the sun would be unknown, esting than the seemingly fantastic extrava- its globe, relative to the stature of man, but in their place would be a color mixture ganzas of Jules Verne. Refusing to regard his picture as mere 1111111111111111111111111,11111111111111111111111111111111111111111. phantasy, Professor Rudaux declares that within certain limits he can reply positively to some of the absorbing questions which Sunrise upon the moon, are asked continually concerning growths seen from a place situ- and geological formations in the heavenly ated at the equator. The bodies. Modern science he says, has pre- central regions are illu- cise data which makes possible a visualiza- minated by the earth tion of the general conditions on the celestial situated in the zenith. worlds. The imaginary traveler would view an unfathom- THE MOON'S LANDSCAPE able space riddled with Were an explorer to travel in the land stars which never of the moon, 239,000 miles away, his wonder- twinkle. ing eye would find high, steep mountains, not unlike our own; huge gray plains, entirely devoid of life, divided now and again rurtreummunon..ull ',mum:eo by gigantic fissures whose proportions have no parallel on earth. the horizon is closer, and therefore objects undoubtedly superior. At sunrise might be The great science of geometry enables disappear behind it at a shorter range." viewed above the horizon the radiant glory astronomers to put easily into actual pros- Consequently the visitor 'could see from one of the sun's corona, and in its wake a series pective all the details which the telescope place, only those craters which are very of gigantic rose-colored flames. Far up in allows them to see in relief under an oblique small and numerous and whose diameters the sky a great disk of light would be seen, illumination. So sharply arc the shadows are of the order of a kilometer." 13 times larger than the moon appears from delineated that they may he seen to elongate, Even stranger to the human eye than the earth. This is the earth itself, which is the as the sun rises or sets for different regions grotesque contours of the moon would be moon's moon. It appears to be at rest, of the lunar surface. This fact, Mr. Ru- the atmospheric conditions. In fact, Mr. though it is not actually so, for reasons con- daux explains, enables man to calculate Rudaux points out, the moon has no atmos- nected with the unequal movement of the exactly the heights of the various parts of phere at all, or at least none that science can moon in its own eccentric orbit. Technic-

this surface: - detect. Consequently, since there is no air to ally speaking, the terrestrial globe, the As for the lunar mountains, the great scatter the light coining from the sun, there earth, appears to oscillate about a mean majority are of such gigantic size that the is an eternal black sky, dotted with stars position-or in other words a position whose movement is not readily discernible to the eye.

EARTH'S PHASES VISIBLE ON MOON The landscape on the planet Mars as visualized in Back of the earth, as viewed from the the evening, moon, the sun and the stars would appear the dusk of filing slowly, appears at the right. The to be whereas actually the landscape con- earth is rotating upon its own axis and bleak, level changing phase, like our moon, with the sists mostly of immense the stars varying position of the sun, from which swamps. Note it receives its light. The position in the in a splendor twinkling sky where the earth will seem to be, changes enhanced by the two small with the position of the observer. How- moons. ever, when the earth is "full" it will shine with intense brilliancy. (Continued on page 1032) Science and Inz'cntion for .ìlarch, 1928 999

Self-adju ling Spark Gap THIS sun dial, be- An Unusual Suii Dial sides giving the time for the pl,,ace in which it is located, also gives the time in many other places in all parts of the world. The model shown is located at Baltimore, Md., and has been giving the correct time since 1892. As shown in the photograph, the dial has many faces, each giving the time at a certain place. Among the numerous points which are ac- An automobile supply com- by this pany has recently placed on counted for the market a self-adjusting clock are: Cape Cod, spark gap. The self-adjusting Cape Town, Jerusa- action is caused by the use of lem, Calcutta, London, a heat responsive metal strip as a side electrode.-The Moto - Honolulu, San Fran- Meter Co., Inc. cisco, Sitka, Pitcairns, Polar Regions, etc. The vanes casting the shadows on the vari- The com- ous faces can be plete spark plainly seen and the gap with hour calibrations for its self- The sun dial with its many faces giving the time all over the world can be adjusting the one in the fore- seen above. It certainly is a unique model. metal strip ground are easily noted. Chemical Spray to Catch Wild Animals WHEN William Beebe, naturalist FOR years it has and man of letters, ex- been the dream of plores the jungle floor automotive engineers of Haiti this winter, to produce a spark he will adapt to scien- plug embracing the tific ends an idea principle of the vari- gained while watching able gap. It has been a caretaker spray the long known that a grass on a golf course. short gap was best for With the same chemi- starting and a wide cals that brought a gap for running. Up host of earth worms to to the present, spark the surface of the gaps have been set at links, Dr. Beebe plans a mean average and to ferret out a small consequently the gap army of tropical un- has been too wide for derground animal s. easy starting and too Dr. Beebe declared short for proper run- that he wished to ex- ning. The new spark pose the idea that most plug is arranged so persons had, that it that a gap of fifteen - was an exceedingly thousands of an inch difficult matter to ob- is provided when the serve and collect wild engine is cold and life. He has recently thirty -thousandths as used several other very soon as the engine has ingenious methods of started. The adjust- collecting animals that able electrode is com- would surprise most of a bi -metal posed Beebe, the well-known explorer will use this system to catch many of his specimens people. strip, which is highly Dr, William responsive to heat. Irrigation Aid, Seen in New Water Pump

The propeller arrangement used to obtain the This illustration shows the complete installa - power can be seen here on the beach. tion operating in a swiftly moving stream. AN ingenious arrangement has recently been perfected to irrigate the land surrounding a stream. It is in the form of a double propeller fastened by a chain to a gear and pump which draws the water from the stream into the irrigation ditches. By using this method it is possible to irrigate a large section of the surrounding country without the expenditure be of great importance in the near future. The complete pump is shown here. of any fuel. This device promises to 1000 Science and Invention for March, 1928

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1 // by eA. Merritt 7tuig; THE MOON POOL", "THE FACE IN THE AiY55"e-#c.

INTO THE PIT. (Sixth Installment)

CHAPTER XVIII "Where is Yuruk?" I turned to Drake, THE sun was high when I awakened, and at his wink and warning grimace f ore - or so I supposed, opening my eyes bore to press the button. upon a flood of clear daylight. As I Synopsis "You men pick out the things and I'll get lay, lazily, recollection rushed upon breakfast ready," said Ruth. "Oh!" She Dr. Louis Thornton is traveling through me. It was no sky into which I was gazing ; Tibet with his Chinese servant -cook, Chiu was looking down into the pool. "Some- it was the dome of Norhala's elfin home. Ming, and two ponies that carried the im- body's been in it. We'll have to let it settle." And Drake had not aroused me. Why? pedimenta. They come upon a white man "I couldn't help it," I apologized. who introduces himself as Richard Keene And how long had I slept? Drake. Drake's father had been very "We won't have to wait. There's a spring I jumped to my feet and stared about. friendly with Thornton. The three decide outside," laughed Drake. He picked up the Ruth nor Drake, nor the black eunuch, was to carry on and come upon Martin Vent - tea kettle and motioned me before him. nor, a geologist, and Ruth, his daughter. there. The latter are guarding themselves against "About Yuruk," Ile said, when he had got- "Ruth !" I shouted. "Drake !" hundreds of soldiers who belong to an age ten outside. "I gave him a little object les- There was no answer. I ran to the door- at least twenty centuries back. While es- son. Persuaded him to go down the line a caping they are attacked and would have way. Peering up into the white vault of the been exterminated, were it not for the bit. Showed him my pistol, and then picked heavens I set the time of day as close to timely intervention of Norhala, a tall, off one of Norhala's goats with it. Hated to nine; I had slept then five hours, more or beautiful, metallic -haired woman, whose do it, but I knew it would be good for his control over lightning and over heavy less. metallic blocks was phenomenal. These soul. He gave a screech, and fell on his I heard Ruth laugh. Some hundred yards blocks, at her command, would make a face and groveled. Thought it was a light- to the left, half hidden by a screen of flower- bridge for her to walk on or form them- ning bolt, I figure, and decided I had been selves into battling monsters to protect `Yuruk,' I told him, ing shrubs, I saw a small meadow. Within her or obey her every whim. Chiu Ming stealing-their-stuff. it, a half dozen little white goats nuzzled is killed in the battle, the survivors leav- 'that's what you'll get, and worse, if you lay around her and Drake. She was milking ing with Norhala. Ruth and Norhala get a finger on that girl inside there.' " one on one of the blocks. The others stand "Then what happened?" I asked. of them. upon a second composed of four smaller Reassured, I drew back into the chamber ones joined together by their own peculiar "He beat it back there like an ostrich - and knelt over Ventnor. His condition was super -normal power. The platforms speed legged rooster pursued by a ravenous smoke unchanged. My gaze fell upon the pool that through space at a terrific rate, arriving with automobile feet," he grinned, pointing eventually in the court of the Metal Em- ran the path had been Norhala's bath. Longingly I looked peror. Angered by the influence of Nor - toward the forest through which at it, then satisfying myself that the milking hala over Ruth, Ventnor raises his rifle the eunuch had shown me. process was not finished, I stripped and and fires at the red ruby-like object he Brieflly, as we filled the container at the believes to be the brain of the metal splashed about. I had just time to get back monster. I-Ie is struck down by a lance outer spring, I told him of the revelations, in my clothing when through the doorway of green flame and rendered unconscious. and the offer Yuruk had made to me. came the pair, each carrying a porcelain The metal monster gives Norhala the en- "Whew -w !" he whistled. "In the nut- tire company to serve as her toys. She Li us pannikin full of milk. takes them to her home, where she in- cracker, eh? Trouble behind and trouble "Oh, Louis," cried Ruth. "You should forms Yuruk, her ape -like eunuch at- in front of us." see the goats! The cutest little silky white tendant, they are not to be harmed. Vent - nor talks, then lapses into unconsciousness things-and so tame. There's nothing the again. Ruth, after telling about the matter with this milk, I can tell you-and strange power that holds her enslaved, that awful black thing isn't around to poison goes to sleep. Drake and Thornton dis- course on the metal intelligences, and it . with his eyes. Ugh -h !" she shuddered. come to the conclusion that they are There was no shadow of fear or horror on guided by some sort of group conscious- her face. It was the old Ruth who stood be- ness, and that they move by super -rapid molecular fore me, nor was there effort in the "steps!" Yuruk. because of smile she jealousy, informs Drake of the way back gave me. She had been washed clean in the to the city, which Ventnor, in a semi- waters of sleep. conscious state, told them was their only "Don't worry, Louis," she said. "I know hope. Yuruk claims that though the inhabitants of the city were hostile, it is what you're thinking. But I'm-me again. much safer to escape. It was all quite true. But I'm going to stay

1w. 1 1 1 1 1 3 And im 1,u .nm 1 -me. don't you worry." nc1J11.1 n rn 1 1 6,IJd, m mgtemns11 nn i nmw ununnnnunuununnuuu uw ununnnne.

It was a metal -city, mountainous. Featureless and smooth, the immense wall heaved heavenward. It should have been blind, that vast oblong face-but it was not blind, and therein lay intangible terror. From it radiated alertness, vigilance. It seemed to gaze toward us as though every foot were manned with sentinels; guardians, invisible to the eyes, whose concentration of watchfulness was caught by some hidden sense more subtle than sight. It was a metal city, mountainous and-aware 1

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,\114 [1rt c. t _¡',,?% 4\ Science and Invention for March, 1928 1001

"I think we had scientific curiosity. But I was not cheerful better start for the -no. It was not fear nor cowardice that city right after lay beyond my shrinking from this ordeal, we've eaten," I nor was it with Drake. It was the night- said, turning back mare loneliness, the helplessness and isola- to the blue house. tion of our human selves alone among the "There's no use unhuman, among creatures that knew our putting it off. How helplessness better even than did we; things do you feel about to whom we were but strange and animate it?" toys, to be played with or broken, as the "Frankly, like whim might be. the chief guest at a We ministered to Ventnor, forcing open lynching part y," his set jaws, thrusting a thin rubber tube Drake answered. down past his windpipe into his gullet and Curious," but none dropping through it a few ounces of the goat too cheerful." milk. Our breakfasting was silent enough. Nor was I. I We could not take Ruth with us upon our was filled with journey. She must stay here with her brother. a fever of She would be safer in Norhala's house than where we were going, of course, and yet to leave her was most distressing. After all, 1 wondered, was there any need of both Drake and me taking that journey? Would not one do just as well? Drake could stay- "No use putting all our eggs in one basket," I broached the subject. "I'll go down by myself while you, Dick, remain to help Ruth. You can always follow if I don't turn up in a reasonable time." His indignation at this proposal was matched only by Ruth's own. "You'll go with him, Richard Drake," she cried, "or I'll never look or speak to you again !" "Good Lord! Did you think for a minute I wouldn't !" Pain and wrath struggled on his face. "We go together, or neither of us goes. Ruth will be all right here. The only thing she has any cause to fear is Yuruk- and he's had his lesson. Besides, she'll have the rifles and her pistols, and she knows how to use them. What do you mean by making such a proposition as that ?" I tried to justify myself. "I'll be all right," said Ruth. "I'm not afraid of Yuruk. And none of those things will hurt me-not after-not after-" Her eyes fell, her lips quivered piteously-then she faced us steadily. "Don't ask me how I know that," she went on quietly. "Believe me, I do know it. I am closer to-them that you are. It is for you two that I fear." "No fear for us," Drake burst out hastily. "We're Norhala's little new playthings. We're tabu. Take it from me, Ruth, I'd bet my head there isn't one of these things, great (Continued on page 1038)

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117 1002 Science and Invention for March, 1928

Can You Answer These Scientific Questions ? SCIENCE and INVENTION Magazine readers, especially our thousands of friends in schools and colleges everywhere, have frequently testified in their letters to the editors that they obtain invaluable help from the columns of this magazine, in clearing up technical questions which arise daily. It is a recognized fact that everyone today, including those of both sexes, are expected to have a fairly good general knowledge of the latest scientific developments and discoveries. It is quite impossible to obtain this knowledge of the latest conquests in science from text -books, as they are usually revised but once a year, and in many cases not as often as that. You will find the questions below a good challenge to your knowledge of modern science, and we advise you to form your own answer, before you turn to the page referred to in each case.

1. What simple, quickly applied scheme would you have tail spins. How would you design an improved airplane used ca trying to save the crew of the ill-fated sub- so as to eliminate the possibility of tail spins? (See rarine S-4? What is your best scheme for raising a page 990). submarine? (See page 978). 7. What is a Newtonian telescope? What is a Cassegrain 2. From your scientific knowledge, do you think it possible telescope? How can air currents be photographed? for one to make a small, simple device, to be worn about (See page 994). the head, which will provide better thought concentra- 8. Is tion? (See page 981). it economical and practical to use electrical heaters for keeping railway switches clear of snow ice? 3. From your knowledge of aviation, would you think it and (See page 996). possible that a flyer coming out of a fog, might fly his plane skyward instead of earthward, when he wished to 9. If you suddenly found yourself on the moon and beheld land? Again, if the pilot wished to turn to the left, the stars, would the stars twinkle? Would the sun would he actually turn to the right? (See page 982). appear larger or smaller than on earth, when viewed by 4. When a fish expels water past its gills, does this action a visitor on Mercury? (See page 998). also help to propel the fish's body forward? (See 10. What are the ten most important things to remember page 983). when driving an automobile in the winter -time? (See 5. Thousands of people have argued the question for gen- page 1004). erations as to whether or not Siamese twins can he 11. Many smokers have no doubt noticed that alcohol does separated. Is it your opinion that this is ever possible? not ignite regularly, when used in pocket cigar lighters. Or only feasible in certain classes of Siamese twins? What is the reason for this? (See page 1005). (See page 984). 12. Do you think it is possible for an amateur mechanic to 6. It has been said that the fatalities among the Pacific build an accurate barometer with which to foretell Ocean flyers were probably due to the planes going into weather changes? If so, how? (See page 1009).

Cable Laying Machine Mechanism Buries Cable Under Ground at Terrific Speed

FLECTRICAL engineering concerns in anism. At the front there is a caterpillar follows up in hack of it and fills up the cut. Germany have made a new discovery tractor provided with an endless chain bucket The method of operation is explained in the in the form of a cable -laying machine, arrangement, which cuts a narrow trench in diagram below and is also quite clearly indi- which promises to promote the supply of practically ally kind of soil. The buckets cated in the photographs. The machine was electrical power throughout the land, at con- elevate the soil to a conveyor, which carries invented by the director of a large German siderably cheaper rates, because there is a this elevated soil backward to a chute. power plant, who is considerably enthused much smaller cost in laying cable beneath Meanwhile, a cable is constantly being low- at the results which have been obtained so the soil, than in putting it on poles where ered into the trench from a cable reel trac- far. Operating with but very few men, at a it must constantly be serviced. The photo- tor, towed by the digging mechanism. As speed of from two to three hundred feet graphs below show three views of the mech- the cable drops into the trench, the soil per hour, it both lays and buries the cable. The photo be- This view is -- - excavatinglow shows the toward the buckets, t h e cable reel end, cable, the con showing t h e veyor, and in cable dropping the foreground, into the the refill chute trench in of the trench foreground and digger. the soil refilling the trench.

The photograph above indicates a side view of the cable - laying machine. Note that the cable reel is mounted on a caterpillar treaded truck, which in turn is coupled to the tractor -excavator. The diagram below indicates the principle of operation.

CONVEYO2.. REEL BUCKETS i

CABLE o TRENCH >'..SOIL REFILL Science and Invention for March, 1928 1003 By "DUNNINGER" MAGIC NO. 60 OF A SERIES ENCHANTED SERPENT MAGNETISM MANY of the readers have undoubtedly SKULL witnessed the clever little trick popu- be East THE illusion below purports to of larly known as magnetism. In this illusion, Indian origin and it has been claimed apparently causes a pencil, secs the magician that it is quite common in Ind:a. One ruler, table -knife, or his wand to mysteri- a dark-skinned mystic reach into a woven finger-tips. In the old a ously cling to the wicker basket, from which he extracts version of this trick, the wrist of the hand examination, this is found small skull. Upon is apparently held for support, but actually, to be the genuine bony substance whiéh at finger of that same hand also in the an extended one time constituted the frame -work the close to the palm. In an- skull is holds article head of a serpent. This snake of the trick, a similar effect is in of other form placed upon the ground directly front by holding a pencil beneath the magician. Mystic obtained the seated turban -headed palm of the hand in such a manner that the passes are then made over the skull, the against the palm. mystified pencil presses the object jaw of which is seen to move. The has a slight advantage over the the presence of This trick spectators arc not aware of first one mentioned, in that the spectators a small boy concealed in the hollow of a The disadvantage lies hundred feet away. see all five fingers. tree from one to several in getting rid of the pencil after the trick A tube leading from this tree serves as a Hence in this, the new cord. has been performed. channel for a piece of thread or thin of magnetism effect, the writer hooks to one por- version the The free end of this cord has employed a stick; but the stick itself is tion of the skull, and permits the bony struc- band, terminating at a lower attached to an elastic ture to rock back and forth on the fastened to the sleeve. The meth- must, of course, be safety pin jaw. The lower jaw ods are just as mystifying and it possesses hinged to the upper and a pair of springs permitting the close the additional advantage of should be added to cause the jaws to show his hands empty at any pulled open by a tug performer to after they have been moment. The performer can also command on the string. It is preferable to run a his finger- from the finger-tips whatever it is that adheres to rubber hose beneath the soil several days A wand can be suspended make an attempt to so that by the aid of a stick as indicated in the tips to drop, and can before the trick is to be produced above. The stick slides into the without fear that the packed and will diagrams catch it in the air the earth will be properly sleeve when not in use. gimmick will fall. leave nothing of which to be suspicious. r.á ,7>»-rzeg. 1, ROCKS

ll lIu IIIIII.11 llll9'ilfl'JIJI'IJI'llClll'lJil'l'lJl'JJIITIII'I'l'f l'JI'lll H 11,j'IllfN 119J1II 1111fIJJllll previously from the scene of thedemonstratfon controls the movements of the skull supposedly A boy in a hollow tree several hundred feet away rubber tube, buried two or three inches beneath the soil. mesmerized by a Hindu mystic. The cord connecting with the skull is run through a thin CHAMELEON The wizard displays a four-sided tube, Jpen at both ends. A white billiard ball, about 21/2 inches in diameter is then passed for inspection. It is dropped into the upper end of the cylinder and falls completely through, but the strange feature is that in falling, it mystically changed in color, becoming a polished black sphere. This ball is again immediately passed for inspection, and the cylinder held so as to enable the spectators to see through it. The diagram explains the mystery. A flap on one side of the tube falls down, causing the white ball to remain above it and release of pressure of the hand permits the black ball to fall. In holding up the cylinder for inspection, the flap drops and the ball rolls into the palm, to be gotten rid of in any desired way. FIND THE ACE Three blocks, with cards on their faces, are placed into a three -compartment box. The doors are closed, and the audience is asked to find the ace. On opening the doors again, it will be found that the blocks have changed places. The effect is produced by having two flaps of tin painted to represent the other two cards not in the compartment. handle either way will Two metal flaps hinged to the door of each of By aid of the tube indicated, a white ball can Movement of the ball. The one or both of the tin flaps to the three compartments permit of a multi. be instantly converted into a black permit either plicity of card changes of the card blocks. white ball previously examined is palmed, and remain behind. It is thus possible to control the black one released. the combination of cards. Science and Invention for March, 1928

sy :77. . anon Q?iamorea Av ID¡ wane /iL1l101s A.p,:^exeaee,,z, 2ezvaz^, 1

- 1 _ ''illll otor Hints

Conducted by GEORGE A. LUERS

CARRYING BRACKETS VERY Chains on wheels arc necessary in snow USEFUL or on ice. Neglect of this carries a risk of injury to car and occupants. DO YOU KNOW-the windshield Many times it is required to haul lengths Do not cleaner will not prevent ice forming of lumber, poles pipes on rush the car through a snow drift or the car. Delays mud hole. on the glass. Gylcerine rubbed on in fixing up around the home or camp, and or There is danger of breaking parts in with a piece of cloth, will keep ice hauling expense, can be avoided, if such the steering gear or even of col- lapsing the front axle. Don't twist the steer- off for an hour or more. Do not, things are brought along on the car. ing wheel if you are putting on glycerine use By means metal quickly on icy streets. This starts of two sheet brackets a front wheel the windshield cleaner or the and straps, as illustrated in the attached skid and a front wheel skid is dangerous. glycerine film will be removed sketch, such unhandy parts can be carried immediately. safely, without loss or mutilation of the car -body or fenders. These clamp carriers can be made up DONT DONT DON'T DON'T DON'T DRIVE NEGLECT OVERWORK YANK CLOSE The automobile dash lamp is a quickly; they detach from the fenders when TO RADIATOR. THE CHOKE. THE WINDOW usually not in use and stow under the seats. Clamp CLOSE. T STEERING SO YOU fixed part, used for lighting up the dash WHEEL CANNOT instruments parts can be bent up cold from strap iron, i 1 only. The method shown in to approximately the shape of the fenders. ON SIGNAL the attached sketch, gives to the lamp an SLIPPERY additional use The slots are cut in, holes are drilled and ROADS. for lighting up the area under the parts are complete. The service of these the hood. clamps will repay the owner many times A simple alteration, to obtain the added for the spare time and effort put into mak- advantage, as shown in the attached sketch. ing them up. Screw holes in the lamp base flange are elongated and enlarged so to make a bayonet joint, readily detached. /POLES, ROD; PIPES OR OTHER MATERIAL A drilled hole and two screws through CAN BE CARRIEp the hood board adjacent to the engine allow BY THESE BRACKETS). for quick transfer of the light to this new position when night repairs under the hood are required. The flexible cord, or conducting wire ob- viously must be long enough to allow for DONT DON'T- DONT DONT DRIVE this change in position. RUSH NEGLECT OVERLOOK IN SLEET OK SNOWDRIFTS. OIL. BATTERY. SNOW WITHOUT CHAINS. HOLDING PARTS FOR FILING DON'T TAKE CHANCES WITH HIGH SPEED DRIVING, IT IS WINTER. A number of "winter don'ts" are shown above. PIECE OF CAR SPRING Avoid driving close behind another car BOLT WORK or a bus, as it takes room to stop the car when icy spots are on the road. If the car slides a bad collision results. Don't keep FENDER the driver's window closed, as signalling is required. Many accidents result from fail- Y5 ßY a" ing to signal. STRAP DETAIL JI Winter driving should be attended by extra I RON OF precaution and care, don't IMPROVISING A VISE CLAMP forget it is Winter. OR HOLDER. FILING A HARD USING DASH LAMP UNDER HOOD TO HOLD SMALL HOLE THROUGH PIECE. FENDER. ELONGATED CONNECTING ROD The details of the carrying brackets are OR STEERING GEAR shown above. A bracket is bolted to each OPENINGS BEARING -CAP. fender and will be handy when carrying lum- FOR QUICKLY - ber, poles --. or pipes. CAR DETACHING le 1461lbA DASH 4°It'e:H, WN WINTER DON'TS Safety in Winter driving is dependent in .: r r.. many respects upon the care used in oper- BENCH ating, maintainance of mechanism and BOLTS WITH use of TWO NUTS. i safeguards required by weather conditions. The most prominent details in connection DASH with winter operation are pointed out in the LIGHT HOLE ANO TWO BOLTS llustraton as "DON'TS." THROUGH To expand on these points : HOOD Two good methods for holding parts for filing It will be understood, if the radiator is BOARD are suggested in the drawing above. not protected by anti -freeze, that a burst SAME system with numerous troubles and expense DASH LIGHT Lack of tool equipment in the repair of USED UNDER the car, can be is certain. HOOD` offset frequently by impro- Oil dilution, with burned -out bearings and vising special holders from odd parts. scored pistons, comes of neglect of engine The sketch illustrates holders which have oil. met the average needs in on This should be changed each 500 miles. II working parts Don't use the choke excessively, as it not of the car. A piece of steel, such as a alone causes oil diluton, but also excessive spring leaf, can be blocked at one end, se- use of starter and consequently a run down it r cured with a bolt at the center and the part battery. Much gasoline is wasted by leav- being worked on is clamped under the oppo- ing the choke out while running. site end by screwing down the bolt. The battery should be kept fully charged, Through means of various heights of to prevent freezing, should have water added ly blocks and a long bolt, this clamp will hold either each two weeks if necessary, to be checked Shown above are the details of dash lamp large or small parts. up with the hydrometer. for the hood. (Continued nn hnnr 1026) Science and Invention for March, 1928 1005 EVERYDAY CHEDIISTRY By RAYMOND B. WAILLS

WHAT INSECT HELPS MAKE THE LIP STICK fume ACOAL SAVER" 'WHAT IT IS? FORMULA IS: 111r1117- SAL-1LN COPPER 15 A RATHER SOFT METAL OXALIC ACID -2-02S WHY USE IT IN BURGLAR PROOF WATER---IGALLON SAFE DOORS? HAS IT ANY MERITS ?

A safe door containing a copper slab twelve inches thick, The red coloring matter in many lipsticks is The above advertised formula has absolutely would conduct the heat from the acetylene torch away due to carmine, a substance excreted by an no merits as a coal saver. There is no ac - from the heated spot so fast that it would require about insect, namely, the cochineal bug. These bugs credited scientific basis for this formula and six hours to pierce the door. Thus copper is better for when killed and dried by heat yield a bril- there is no reason why it should be used. safe doors than steel would be. liant scarlet color.

WHY SHOULDN'T THE VALVES OF FOR EVERY TON OXYGEN CYLINDER BE OILED? OF COAL BURNED IN YOUR FURNACE, HOW MUCH AIR IS USED?

A NEW THEORY AS TO HOW SOLDERING FLUXES ACT HAS BEEN SET FORTH. Most soldering fluids contain chlorides. It has been proven that these decompose into hydrochloric acid gas, which in turn drives out the air between the metals, and thus Oil is inflammable. In contact with corn- enables the solder to run in, making a For every ton of coal which is burnt in a furnace about pressed oxygen, a serious explosion is very tight joint. fourteen tons of air are needed for its combustion. likely to take place.

IS BANANA OIL MADE FROM HOW MANY KINDS BANANAS? OF ALCOHOL ARE WHY DOESN'T THERE? ALCOHOL WORK WELL. IN THE POCKET CIGAR LIGHTERS?

Banana oil is not made from bananas. It is There are some sixty different kinds of alcohols. Alcohol absorbs water from the air, until it con - largely composed of amyl acetate, which is a Among them are the famous ethyl, the deadly tains about five per cent of this non -burnable very good solvent. It is largely used as a methyl, and also amyl, butyl, propyl, allyl, and fluid. This added water makes the cigar lighters vehicle in gold and aluminum paints. cetyl, besides many others. difficult to ignite when using alcohol for fuel. 1006 Science and Invention for March, 1928

, '------. s,i.;iè: G as Range Wins This Month's Cup Model Built by Nathan Klein, of Philadelphia, Pa.

Photograph shows Nathan Klein and his prize-winning model.

Iii

This very remarkable model of a range was built of 12 -gauge iron and 3/3 -inch and 1/2 -inch channel iron, entirely by hand. The panels of the doors were ham- The trophy hered out on a piece of lead, to shape them as the cup is just 1 photograph shows. No bolts show on this model. inch taller It is bolted on the inside as much as than the possible. Only one pattern was used model. for the burners.

The photos on either side show the model. The two long burners were made of a piece of 1/4 -inch pipe, with a 1/8 -inch nipple on one side. The other end of the burner is connected to a 1/2 by 1/2 -inch bushing, and the point of a plug inserted. and cut out for an air mixer cap.

All the enameling on the model was done at 1 a foundry, after each ^` part had been con- The hinges on this model are concealed and the springs structed by hand. The model does everything that a full-sized range are of the invisible type. The handles are of iron filed to will do; it will cook, bake, broil, or fry on a small scale. It uses the shape and then enameled. The knobs are also hand -made regulation illuminating gas. It is 171/2 inches high over all, 141/2 inches with a file, and nickel -plated. The cooking top was made wide, and 81/2 inches deep. of l/2 -inch angle iron and the frame was cut out of 16-gauge iron and welded to it. (Rules for Model Contest appear on page 1)44) Science and Invention for March, 1928 1007

The MacLeod Vacuum. Gauge By ED. V. SUNDT

F you had to measure a pres- barded by the millions of elec- sure one -billionth that of at- trons which constitute the cath- mospheric pressure; how CLAMPS ode rays. The glow disappears would you go about it? Its mag- PADDED again as the tube is evacuated below .005 mm. of mercury. The nitude relative to atmospheric TO VACUUM WITH FELT pressure would be as 18 inches is gas is most effectively driven off, to the 238,000 miles over the dis- LI NE however, by heating the glass to tance from the earth to the moon. about 400° C. The metal parts are heated to a white heat by THE MACLEOD VACUUM GAUGE means of a radio frequency in- BULB TO By means of a glass instru- duction furnace. The heating ment, known in scientific circles PREVENT must' be done, of course, while as the MacLeod Gauge, such in- ACCIDENTAL the tubes are being evacuated. the finitesimal pressures may actually OVERFLOW OF As our pressure decreases efficiency of the gauge increases be "magnified," so to speak, a MERCURY million times or more, and the in a geometrical progression. pressure read directly in terms of Thus at 25 mm. from b -b1 the millimeters of mecury. (760 mm. initial pressure would be multi- of mercury equals 14.7 lbs. per plied 40,000 times, which means sq. inch of atmospheric pressure.) it must have been 25/40,000, equalling .00066 mm. of mercury. The simplicity and accuracy of FINE GAUZ E This is approximately the pres- its calibration make it popular, TO EXCLUDE not only as a calibration standard sure a radio tube is pumped to DUST for other vacuum measuring de - when being manufactured. The 'vices, but in the manufacture of tube "hardens" with use, or in products which make possible other words, the pressures de- tungsten man's greatest achievements. OFT RUBBER crease, on account of the in the filament combining with Radio, television, X-ray surgery VACUUM and other things vital to our the residual gases. present civilization, would be im- TUBING If the mercury comes up to possible without the use of high within one mm. from the top of vacuum. "E" the original pressure would be "magnified" 1,000,000 times OPERATING THE GAUGE and the pressure read would be Referring to the sketch, it will .000,001 mm. of mercury, which be seen, the bulb "A" is a sort of is about the pressure in a good reservoir The mercury is X-ray tube. "sucked" up in the glass tube "B" The instrument described is as a 10,000 to 1 ratio when a vacuum is drawn in the by electricians in known The Macleod gauge has been used for many years is ratio of the gauge, to about the point a -a'. their work on high vacua. The description makes it clear how this gauge, which the Let us assume the gauge has been very wonderful instrument can be constructed so as to determine the capacities of C to E. Small ratios of any vacuum, however slight the pressure is. 1 connected to a vacuum line which amount such as 400 or1,000 to are more has been pumped to .01 mm. of common, being easier to make. mercury, and we will proceed to take a height of the mercury in the tubes E and F, They answer most purposes however, for reading. we find, is 100 mm. In other words the gas while their sensitivity is proportionally less The bulb A is raised, by means of the hand pressure in E just counterbalances the weight it is very seldom a vacuum higher than wheel on the pinion and rack, causing the of a column of mercury 100 mm. high. But .000.01 is obtained. To read higher vacua it mercury to rise into the bulb C and the tubes the pressure in E is 10,000 times the initial is also necessary to cool the mercury in the D and F. When it reaches the height b -b' pressure, which then must have been 100/- gauge to 0° C. or less, to prevent its vapor in the tube F which is level with the inside 10.000, equal to .01 mm. of mercury. pressure from affecting the reading. top of the tube E, the reading is taken. The height the mercury rises in E, of In radio work, especially, the determination Let's see what has happened. course, depends on the degree of vacuum. If of vacua in bulbs is of extreme importance, The mercury in rising up the tube D, im- it rises to 50 mm. from b -b, the volume of because hard bulbs, containing almost a per- prisons the rarified air, or other gas, in the 1,000 cc. would be compressed to .05 cc. or fect vacuum and soft bulbs, containing a cer- bulb C. As it rises higher and higher in C 1/20,000 of its original volume and the origi- tain amount of gases must have their pres- the residual gas is pushed up into a smaller nal pressure will have been 50/20,0000, equal sure accurately determined. There are other and smaller volume until at last all the gas to .0025 mm. of mercury. uses for this gauge in the electric field as in formerly in the large bulb is contained in the X-ray work and neon tubes. It is fair to say mm. in PECULIARITIES OF GASES AT LOW that the exact determination of low vacua is small tube E, which is usually 100 PRESSURES length. It is closed, of course, at its top encl. acquiring more importance as time goes on. The capillary depression offered to mercury At about these pressures a gas behaves It will be seen by reading the article that any by E is balanced by that of the tube F which somwhat like a thick, viscous fluid and degree of sensitiveness may be given to the is of the same inside diameter. flows very slowly. When evacuating a gauge by changing the proportions of its Suppose the capacity of C is 1,000 cubic radio tube, for instance, it clings to the glass parts. It is a question of ratios or relations centimeters, while that of E is .1 cc. One bulb and metal parts somewhat the same as of volumes or rather of cubic contents. thousand cc. of gas is thus compressed into molasses would if being poured out of a dish. NEON LAMPS IN THE DARK -ROOM a space 1/10,000 of its original volume. Ac- Cathode rays, formed by the application cording to Boyle's law in physics, disregard- of a high frequency spark coil to the ter- Neon lamps have been recommended for ing the small temperature changes, the pres- minals at this time, will agitate these layers photographers' use in the dark -room. It is to sure of a quantity of gas varies inversely as of gas violently and the tube will gradually be noted that the lamp should be tested for the volume it occupies. The pressure in E begin to glow with a white light as the gas actinism, as some are unsafe for such use. then must be 10,000 times greater than the begins to get stirred up. What really hap- A noticeable improvement will be obtained lamps. former pressure in C. The difference in the pens is : the adhering gas molecules are bom- when using the right type of 1008 Science and Invention for March, 1928 Water and Its Impurities By DR. ERNEST BADE WATER is taken too much for fested with a tiny plant giving the water a Iron salts, if present, must be detected granted. Although it covers three- cucumber -like taste. Such contaminations of either as ferrous or as ferric salts. The quarters of the earth to an aver- water supplies are extremely rare, except in ferrous salts are present if the test solution age depth of a mile, only a minute waters that are not used by communities for turns light blue when potassium ferro fraction of it is fit for human consumption. drinking purposes. Living plants and ani- cyanide solution is added; a deep blue color Before the water can be piped to the users mals are abundant in some places, as well as and precipitate is formed when potassium in cities and towns, the water in many places dead and decaying organic matter. Then, ferricyanide solution is added. The ferric must be purified, and this may be accom- too, many different kinds of gases are dis- salt is detected by adding a drop or two of plished quite readily by large sand filters, solved in the water, such as oxygen, carbon chemically pure hydrochloric acid to the test chemicals, and settling tanks. Any of these dioxide, nitrogen and, sometimes, hydrogen solution and then adding a few drops of methods, or a combination of them is used, sulphide, as well as other rarer types. ammonium sulphocyanide solution. A deep depending entirely upon the impurities found. One of the commonest constituents in red coloration indicates the presence of ferric Really pure water is never found in nature, water is chlorine in the form of salts. salts. although ice, snow, and rain water are nearly Acidify with a drop or two of nitric acid Salts of aluminum and phosphoric acid so. Even in distilled water certain impuri - and add a few drops of silver nitrate solu- are detected by evaporating about 2 ounces tion. A white precipitate or milky appear- of the concentrated test solution until the ance shows that a chloride is present. Sulphuric acid and sulphuric acid salts, sulphates, are detected by acidifying a small portion of the water with hydrochloric acid and adding barium chloride solution, first heating the water nearly to boiling. A white precipitate indicates the presence of a sulphate. Lime water added to the water (before it is boiled) will show the presence of carbon dioxide dissolved in the water, by giving a white precipitate. Calcium or lime in water is detected by adding a few drops of ammonium carbonate to a small test portion and then adding ammonium oxalate. If calcium is present, a crystalline precipitate, calcium oxalate, is formed which is white in color. Magnesium salts are detected by making a small test portion alkaline with a little ammonium chloride followed by ammonium hydroxide and then adding a few drops of bisodium phosphate solution. A white precipitate, crystalline in nature, appears if magnesium salts are present. mineral matter found is more exten- Acidify a small portion with hydrochloric acid The and then add a few drops of barium chloride. sive and variable. The more ordinary con- The presence of a sulphate is shown by a Heat the precipitate strongly. If it turns stituents are salts of lime, magnesia, soda. white precipitate. dark, too much organic matter is present. If and the latter is also ignited, a characteristic odor may indicate potash and ammonia, nitrogenous matter. This odor may even be found free. Then there may be such acids mixture in the evaporating dish is just moist. putrescent. as hydrochloric, sulphuric, carbonic, nitrous, Add a few drops of nitric acid (dilute) and nitric, and, at times silicic or phosphoric, divide into two parts. To one part add a ties may be found if the water distilled con- even iron and aluminum tained comparatively large present. Sometimes few drops of ammonium chloride. Filter if amounts of such salts make themselves felt, the former in not clear. Then add ammonium volatile substances as ammonia. This am- hydroxide chalybeate springs, hut, usually, the most until the solution smells of it. The presence monia passes over with the first, the later salts of calcium (lime distillate being pure. common are the of aluminum is shown by a white flocculent salts) and sodium. precipitate. The remaining Water usually contains three types of im- half of the solu- The hardness of water is mainly due to tion, which is also filtered purities, that is, waters as found in if not clear, re- wells, carbonate and sulphate of calcium in the ceives an addition of ammonium molybdate water. The former produces temporary hardness because it precipitates out on prolonged boiling. The latter alone or together with chloride of calcium and magnesium produce permanent hardness. Hard water is not only injurious to health because its power as a solvent for food is impaired, but it directly impedes digestion. It is had for washing, because a very large quantity of soap is used, first to neutralize the hardness, and then only for its cleansing use. The quantity of soap required for softening the water depends upon the quantity of salts dissolved in it. The calcium carbonate (carbonate of lime) destroys about ten times its weight of soap. Water affected by temporary hardness may be softened by the addition of sodium carbonate or by boiling for 15 minutes. This removes the hardness. One quart of river water may contain about 8 to 9 grams The presence of a chloride is easily distin- of mineral salts. A quart of ocean water guished by the addition of silver nitrate solu- 40 more than tion to a test portion. The test tube contain- contains about grams, three- ing the precipitate shows the presence of a quarters of which arc common salt. Magnesium salts are detected by making a chloride. Heat the test tube of water, add a The mineral impurities in water may be test portion alkaline with ammonia, and then few drops of nitric acid, and then add the adding a few drops of sodium biphosphate. silver nitrate. found by qualitative analysis, evaporating A white precipitate forms if such salts are the water to dryness and testing the resi- found present. springs, lakes and rivers. These consist of due. For general purposes, it is sufficient organic matter, mineral matter, and gaseous to test for some certain definite substance in solution. Warm the test tube slightly, to constituents. Of the first, that is organic the original water or after it has been con- about 50 C. A yellow precipitate shows the matter, New York City had a taste some centrated by evaporation. The latter method presence of a phosphate. years ago when its water supply was in - is to he preferred. (To be continued) 1009 Science and Invention for Marc/i, 1928

IIow to Make a Barometer at a Cost of Six Dollars A Cheap and Serviceable Instrument Which Can Be Built By RAYMOND B. WAILES

the mercury -filled and stoppered barometer - bottle, AMERCURIAL barometer can easily tube is inverted and thrust into the be made by the handy man from the end of the barometer tube will be under about six dollars worth of materials. the mercury which has been poured into If properly made, it will be of real the bottle. Now by pulling on the wire value to his household, functioning accurately twisted to the leather stopper, the stopper and dependably as all good barometers can be pulled out of the tube. The mercury should. Perhaps past experiences with cat- will begin to come out of the inverted tube gut, hair, gelatin, paper, burned out electric and enter the bottle. If a thirty-six inch light bulb, dripping bottle, and the host of tube is used, there will be about thirty inches other makeshift and so-called barometers of mercury still left in the tube. will deter many a handy man from making The barometer tube should, from now on, a mercurial type of barometer such as be handled as carefully as one would a ladle described here. But this should not be; of molten iron. If the tube is raised quickly, the mercurial type is the standard by which the mercury will rise in the tube and whack others should be judged. the closed end of the tube with such force The essentials for the barometer are a that it might break it, and then again, if it barometer tube which can be bought from is lowered suddenly, the mercury will fall dealers in chemical supplies for about fifty from the tube, and in reentering, will carry cents, a bottle, and about two pounds of air with it, making the barometer worth- mercury. The barometer tube is a thick less. If one bubble of air is seen bubbling walled glass tube, closed at one end and up the column of mercury, the tube should having about an eighth of an inch inside be emptied of mercury, refilled and inverted bore. Lacking a barometer tube, a straight again, i.e., the work must be done all over length of heavy glass tubing of about one again. eighth of an inch or one quarter of an inch The barometer tube can be mounted in inside diameter, about 38 inches long, and an open case built especially for this pur- closed at one end, can he used. The end pose. A block of wood bored out to receive The. above photo shows the well of the can be closed by holding it in a flame, barometer. the well, or bottle -reservoir is to be attached rotating it while it is being heated. to the bottom of the case. A perforated cork The first step in the making of a barom- is filtered through it, can be thrust over the tube and into the neck of the mercury. This cury when it tube up- eter consists in purifying had. this bottle -reservoir will keep the can be most easily done by filtering through The clean filtered mercury should then right. A very small channel should be cut hole in page 1054) chamois, or through a very small be poured into the barometer tube which (Continued on the end of a paper cone. One of the photo- should be first cleaned with a mixture of graphs shows how such a paper cone is sulphuric acid and potassium bichromate. rolled to make then washed with water, followed by a the filtering, or washing with lye water and then several purifying funnel rinsings of water after which it is dried. as it could be The drying is very slow ; it can he hastened called. By pull- by rinsing with alcohol a couple of times. ing up tight, the By drawing out to a fine point, a length of paper seam can be glass tubing and fastening this to the end of closed so snugly the stem of a small funnel, a filtering funnel that no mercury will be had which will enable the mercury will flow f r o ni to be poured into the tube without spilling. the cone, and by Pour in about four inches of mercury. Now allowing the fold with a Bunsen burner, slowly play a flame up to slip a trifle, a and down this part of the filled tube. Soon small hole, which the mercury will conic to a boil, and drive will keep hack the out all the air bubbles between the mercury dross of the mer- and wall of the tube. This operation may be omitted if the tube and the mercury is .ltnnumreismillImmuctgnlurun, clean, but even then, some inaccurracy of the finished instrument will result. After this boiling, drop in more mercury so that an- The photograph at is added. Boil the left shows a other four or five inches front view of the this, and repeat until the tube is filled and completed barom- at room temperature. Do not attempt to eter, which can be at once. Tapping the made at a cost of boil all the mercury about $6. Most of side of the tube will cause the mercury to the supplies can be break up and fall into place in the tube. bought from a chem- The most important part of the barometer ical supply house. The barometer tube construction comes next. This is inverting can be mounted in the tube into a pool of mercury. One way - an open case built of doing this is to thrust a little leather especially for this tube purpose. A block stopper into the end of the barometer of wood to receive so that it is stoppered up, and on inverting the reservoir is at- the tube no mercury will fall out. Fasten tached to the bot- around the leather stopper. tom of the case. a piece of wire Procure a small bottle about three inches high and having a wide, or salt, mouth. Pour The scale s fixed behind the enough mercury in this bottle so that when barometer tube. 1010 Science and Invention for March, 1928 Magazine Mysteries By BERT DOUGLAS

THREAD PARCEL LEDGE A copy of a magazine is shown on both sides EPEE Three magazines are put on the table and a and the pages run through. A rubber band is The parcel of ar- spectator is instructed to insert a card in placed around the same and from the interior ticles is wrapped the center of any of the magazines he wishes a seemingly inexhaustible supply of silk hand- in a large hand- while the performer is out of the room. 'The kerchiefs, ties, pens, bags of gold or rabbits kerchief located on magician returns and instantly tells in which and pigeons are removed. If desired the mag- the ledge behind magazine the card had been inserted. This azine may be opened repeatedly to prove that it the table. A timple stunt may be performed at any is empty, yet the various objects may be re- thread is attached house party and books can be used instead moved immediately thereafter. Solution is given to the parcel and of magazines. The secret lies in a tiny piece at the right. to the bottom of of thread which is laid on the lower right the magazine so hand corner of all the magazines. When that when the the spectator opens one of them to insert Any copy of a magazine is magazine is turned the card the thread is displaced and this taken and the alternate upside down the gives a clue to the performer as to which pages are cut narrower as parcel is lifted into book houses the card. illustrated. Models of cars it. Goods are then are then cut from adver- produced. tisements and inserted between the long and short page. It will thus be seen that in running through the pages the short page will fall behind the long page unseen and on going back through the magazine in the opposite direction the reverse will be true and the automobiles The method of cutting the pages of the magazine will come into view. is illustrated above. 4-0(4(- A page of a newspaper (a) is shown and then doubled (b) and some strips of colored paper put into the bend. It is allowed to open (c) and the strips have disappeared. Words may appear on the open paper. Secret - The lower half is double; the head line on one side and regular matter on the other side of the doubled part. Only one of the duplicate members is dropped; the strips are concealed in the bend.

A cardboard tube iP shown empty. It is covered with two pieces of a magazine page which are secured by rubber bands. Two silk handkerchiefs are shown. One is selected and vanished and is instantly produced from the tube. Secret -Each hanky has a duplicate concealed in a double sheet of paper. When bursting the paper the kerchief is naturally removed. This is an excellent simple trick, and will always fool the spectator. -> 4-(e A sheet of paper is rolled into a cone, a watch or handkerchief dropped inside and when the paper is unrolled and shown on both sides the watch will have vanished. Secret- Two sheets are gummed together with the exception of the corner illustrated. The watch is dropped into the space between the two sheets and thus when the paper is unfolded the watch is gone. Science and Invention for March, 1928 1011 A Few Tricks with Magazines Impromptu Magic Which Can Be Performed by Anyone Without Expensive Apparatus, Using Only Materials Found in the Average Home

this on which we will describe If alternate pages of a magazine are the magician. The magician sets the N the first effect tube and and which is illustrated on the opposite clipped and a photograph or drawing of an table. Now, taking a cardboard both sides. automobile is then inserted between each tearing two pages out of a magazine, he page, a magazine is shown on of inside of the magazine toward long and short page, ruffling through the covers both ends of the tube with a sort With the Vanishing the silk the audience, the issue is ruffled out and the magazine from one direction will make the drum -like diaphragm. illustrations disappear, whereas handkerchief in any of the usual ways, such pages run through rather rapidly, indicating automobile or confined within them, if the pages are run through in an opposite as by the means of a pull, a rubber band that there is nothing and while appar- other than the printed matter. The per- direction, an auto will be seen on every by rolling it into a ball, magazine on the one of them. ently throwing it away, snapping the ball of former leaves the open the van- or two, as is shown, The fourth effect, illustrated on the oppo- silk under his waist -coat, he causes table -top for a moment come out it upsidedown, so as to site page, requires a little imagination to ished handkerchief to apparently and then turns of the cardboard tube. The show the opposite side and prove that empty. make the modus operandi clearer. At A we of the center see newspaper which apparently is doubled effect is very pretty, because the tube is He now proceeds to remove ties, pens, ker- a interference. objects from the up as shown at B, and into this open sleeve, sealed against any external chiefs and various other -head on either side is burst interior of the magazine. The spectators pieces of a paper ribbon are dropped. The When the drum possibly paper ribbon has previously been torn into with the tip of the finger, the kerchief is wonder how this material could indicating clearly that have gotten between the pages. The secret short strips, about an inch or so in length. carefully \vithdrawn, it comes from within the drum. The mode is quite simple. Suspended from a When the newspaper is again unfolded, the itself is quite simple. A handkerchief ledge on the back of the table, the load is strips will have completely disappeared. The of operation is first carefully rolled into as small a pocket tied in a handkerchief and then, by means secret lies in the fact that two newspapers as possible, yet with care so that it does not of a thread, is attached directly to the back arc actually employed. Let us say the first is used. One first page is doubled on make for bulkiness. This is placed be- of the magazine. When the magazine is sheet and empty back itself so that the running head is facing into tween two adjacent pages of a magazine turned to apparently show an Thus when appar- lifts the load behind the the fold. The bottom half is then glued to the pages glued together. cover, the thread one page out of the magazine, pages, after which the load is opened and the complete first sheet, forming a flap, as ently tearing the detailed drawing shows. It is then obvi- the magician actually removes two pages, the material removed as desired. the blue silk is quite self- ous that if the back sheet is held, the other placing the one containing The second effect shown side of the cardboard in placing four or piece pasted to it hangs down in a sort of handkerchief on one explanatory. It consists one with the yellow silk on different periodicals on the table -top inverted V position. The whole paper is tube, and the more the other side. He can now remove either and asking anyone to insert a card within the folded up to apparently house the paper is desired. pages of one of them while the magician is ribbons. Thereafter the lower half silk tell dropped, the V -like pocket concealing the A simple method of vanishing either a out of the room. On his return he can of the has been opened. ribbons. By adding a second V, it is possible watch or a handkerchief is by means at a glance which magazine is removed must be instructed to cause a torn paper ribbon to convert itself cornucopia. Here again a page Of course, the audience magazine ,rolled into a cone and a secrete the card near the center fold. into a whole ribbon again. After the trick from a to a handkerchief dropped in. On this is that a tiny speck of is produced, the entire sheet is crumpled up watch or The reason for it will be found that the on the lower right-hand and thrown away. In this manner the mode opening the cone, thread is placed watch has disappeared. The effect is pro- corner of each cover. Consequently, when of getting rid of the contents is not observed. silk hand- duced by gluing two sheets of paper together a is opened, the thread is accidentally In the next effect, two colored cover so as to form a pocket, as indicated in the off. This thread is the magician's kerchiefs are passed for examination, and brushed handed to diagram on the bottom of the page. cue as to which magazine contains the card. then one of them is chosen and Making Driftwood Furniture Those Articles made of desired pattern. Japanese driftwood portions of it which to can be observed arc always add charm then charred with a the room in which blow torch, to a depth they appear. While illus- sufficient to give them the photographic a fine, even layer of trations on this page charcoal. Now with show only a Japanese or even photo a wire brush, driftwood a stiff scrub brush, frame, and the method nearly all of the in which it was made, charred wood is re- it is entirely possible moved, the amount de- to duplicate the effect pending entirely on the on wood and then use desired color. This that wood for the wire brushing leaves making of small the hard portions of chairs, stools, tables, kind the grain protruding or, in fact, any above the softer and of furniture desired. more easily burned Ordinary relatively wood. A coat of shel- cheap stools can be lac, followed by an converted into drift- application or two of wood stools by follow- furniture or floor wax, ing the method de- completes the job. scribed herewith. Polychrome finishes For the driftwood, can be produced on nearly any kind of áriftwood by painting wood will do, even with one of the new that from ordinary rapid -drying enamels packing boxes. One and then, after this of the best woods is dries, covering with a cypress, with a fine different color, and curly grain. The ma- rubbing down with dry terial is cut to the de- cloth, while the second thickness and sired The driftwood frame surrounding the photographs was made in the manner described coat is still wet. shaped to and 2 shows the width, or in the accompanying article. Photo 1 shows charring the wood, -f1'al(,r E. Burton. conform with its final wood being wire brushed. 1012 Science and Invention for March, 1928

F . :I . P./'°../'f f_l. fl'J711Y'.J'.ISSiYi^J''rY'1'.Y'.r./'J'J'.l.PlJ'J s._"...... ^Y/'J'J°/'.FT-P .....:.

ARTICLES OF INTEREST TO EVERYONE ti NOVEL LAMP HOLDER DOUBLE MUSIC IMPROVISED WORM DRIVE Many unique effects can be obtained by playing two or more grooves in REDUCTION DRIVE FOR a phono- SMALL MOTOR graph record, at the same time. Take a soft piece of wood and drive it into the phonograph needle as shown. Next, take two other needles and drive them into the stick, one at each end, with their points projecting. These should be parallel to the first needle. An ar- IMDROVISED rangement of this nature will give what is WORM known as an "echo effect."-Ellis L. Roney, Reporter No. 28403.

REPRODUCER TOOTHÁRED

/WIRE WOUND TO PITCH OF STICK GEAR TEETH

NEEDLES I

The above illustration shows some of the uses of the lamp holder described below. WIRE ATTACHED RECORD TO SHAFT BY BENDING ENDS OF INTO DRILLED HOLES A combination electric light bulb pro- One of the simplest forms of making a worm tector and holder can he made from a wire drive is through the use of a toothed wheel spiral and a small wooden knob. The lamp The details of the double reproducer for the and a worm made by coiling and fixing a is top phonograph are shown above. piece of wire to the shaft. The wire should cord brought out through the portion be wound to the same pitch as the gear teeth. of the knob and the wire is fastened to the The ends of the wire are fitted into holes bottom of this knob. The lamp may be drilled in the shaft and is thus kept in place. hung in any position or placed on the floor The body of the worm can be made from a GREASE CUP KINK piece of brass, drilled to fit the motor shaft. and should prove to be exceedingly useful The simplicity of this idea should appeal to in the cellar and in the garage. Heavy wire, mechanics doing experimental work.-G. A. which will hold its shape well, should be used Luers. for the spiral. A chair spring would supply the wire. REMOVABLE WINDOW BARS

IMPROVED MOTOR BASE TOP VIEW

CHAIN STRETCH PIPE SPACERS BRACHET3I IS TAKEN UP í1J WITH MOTOR f ADJUSTING CHAIN SCREW Small grease cups, inconveniently located, DRIVE can be easily removed by soldering a long cotter key to the cap. The two halves of this key will have to be bent at right angles as shown. The other key forms a handle and ADJUSTABLE s is placed through the eye of the upright key. BASE l/i -Frank W. Bentley, Jr.

-111

MOTOR- FCON DATION PROTECTING THE IGNITION

SMALL HOLES. DISC OF SHEET FOR DISTRIBUTOR RUBBER TO FORM WIRES WATER SHIELD FOR EYE BOLT LOCK STEEL PLATE FORMING DISTRI BU TO THE BASE FLANGE Removable bars for The above drawing shows the construction of the window may be made the adjustable motor base for keeping the as shown above. drive tight. Many shops and factories have the win- For maintaining a drive chain under the dows barred with iron or steel. In the case proper tension, one of the most practical 'of fire this may prove to be disastrous, and means is to mount the motor on a base the illustration shows a means of allowing similar to that shown in the illustration. A these bars to be removed. The bars are steel base plate is made with holes for secur- spaced by pieces of metal tubing. Instead of ing the motor and slots for the bolts to allow The distributor on the automobile may be the lock, as shown, an ordinary pin or bolt for end adjustment. A section of the plate protected against water as shown. A disc of with a nut at one end may be used. When it sheet rubber forms a water shield. Small is bent and fitted with an adjusting screw. holes will have to be cut in the rubber to is necessary to use the window as an exit, the It is possible to use this adjusting base with- allow for the passage of the distributor wires. flange is removed and the bottom bar slid out change in the installation.-G. A. Luers. out.-Herman R. Wallin. 1013 Science and Invention for March, 1928 Readers Forum anything to say, this is the place to say it. desires to hear from its readers. It solicits caustic or not. So if you have to SCIENCE AND INVENTION limit your letters to 500 words or less, and address your letters comments of general scientific interest, and will appreciate opinions on Please Magazine, 230 Fifth pro and con will be aired on this page. Editor-The Readers Forum, c/o Science and Invention science subjects. The arguments York City. This magazine also relishes criticisms, and will present them, whether Avenue, New

After the phenomenon or prin- a mirror, i.e., heliograph and Bell and 'fainter's TRUE rank of science. photophone down to present day ciple is discovered he finds a use or a second use experiments on an Lditor, SCIENCE AND INVENTION: for his work on phonofilms. Now why not; if given not enter your for it. Science text books do not cater waves, modulate Though an astrologist, I did needs. He wants a list of phenomena and prin- unvarying source of (short) radio contest, as I considered it a waste of time and to. IIe same at and by the reflector? If feasible, this ciples and of the uses they have been put of the trans- effort. has to and is quite willing to grant that the sci- would allow the heavy machinery Nevertheless, I want to make a prediction and or principles mitter to be fixed, while the modulator was moving a prize in your entists who discovered the phenomena easily see only very that is that you will never award knew their business and, therefore, is only slightly round. At present I can astrology contest. Your articles have been so dis- short waves could be used and for short signal dis- to award interested ín the scientific and mathematical improvement may unjust, so bitter and so prejudiced, that cussion that the specialized expert revels in. For tances, but experimentation and a prize would mean that you must acknowledge effect"-find produce something practical. in astrology and this you example: (a) granted the "Edison A. MASON, that there is something a use for it-answer (by Fleming) the two elec- would not have the courage to do. So you will Victoria, B. C., Canada a lot of trode vacuum tube. (b) Expansion of gas under quibble, hedge and equivocate, and find and gas engines. (c) no prize should be awarded, just as heat-use for it-steam excuses why "Hall effect"-uses-what are they? THE EDITOR REPLIES you have done in other matters. 2. Inversely he needs a list of known means to This is a prediction that is going to come true, (We thank you both for your bouquet and even yet. produce a result e.g. detection of radio waves- the which the poor contestants have not realized as crystal-audion-mercury carbon-electrolytic-mag- felt a pleasurable sensation as you wielded E. T. JOHNSON, has knife. N. Y. netic detector, etc.-in order to see if his idea Magazine has Pleasantville, heretofore used. SCIENCE AND INVENTION (More than a year ago, SCIENCE AND IN- been always tried to explain the way things work. VENTION Magazine predicted that the astrolo- We have not entered into the very heavy con- gers could not give a correct horoscope. At this structional articles, because the construction of late date you have finally come to the conclu- a bridge or a building is that type of engineering sion, perhaps through astrology, that no prize in which most of our readers are not interested. will be awarded. We certainly would not con- It is only the outstanding marvels in this field sider this an example of a forecast. smr'm that are covered, but we daresay that there is we did not hedge, or tic has covered the But we did not quibble; no publication in the world that equivocate; the only reason we gave as to why IN THE subject of television as completely as SCIENCE no prize was awarded was because no astrologer MARCH ISSUE AND INVENTION and her sister publication, could even approach the conditions imposed upon RADIO NEWS. There is a book called, "All him. In not one instance did we have a horo- TEN MILLION MILES About Television," containing some of the ar- scope that even approximated the facts. We pub- SUNWARD, by Geoffrey ticles which appeared in SCIENCE AND INVEN- lished some examples; the others are on file at Hewelcke.' We wager that TION. It has 112 pages and is of the same size these offices. If any astrologer believes we were the interest that this story as this magazine. If you are interested in that unjust in announcing that no rewards were paid, subject, we recommend this publication. horoscopes which he will arouse will be as great as that of that the ama- and if he believes that the "Doctor Mentiroso." While it has nothing We do not agree when you say, drew up are accurate, now that the facts are Fourth Dimension, it teurs are being rapidly driven away from the him immediately write the editor. to do with the of size radio sets by factory known, let evolves a most novel point to change the construction large -EDITOR.) It is built models. As a matter of fact, an amateur axis of the earth by human energy. be one; he delights in working up one of the cleverest stories of this kind will always A BOUQUET AND A KNIFE new circuits of his own or in building apparatus that we have ever seen. And when you embodying the new circuits which are described Editor, SCIENCE AND INVENTION: have finished the story, we will ask you for some years, I in various publications. Many manufacturers From reading your magazine what is wrong with it. are slow to take advantage of new circuits, so notice you are good enough sports to stand being amateur is always a step ahead. approached with a bouquet in one hand, a knife BARON MÜNCHHAUSEN'S SCIENTIFIC that the active Hugo Gernsback. In We likewise believe that this publication offers in the other, and a sheaf of suggestions, good, bad, ADVENTURES, by for getting informa- installments 3 and 4 the wily Baron gives any reader an opportunity and indifferent, in the pocket. tion and at no time is he made to feel that he The Bouquet. You are to he praised for your us in detail a picturesque story and de- that it is quite all times to explain how and why description of his space flyer, his trip to the is an intruder. It is conceivable attempt at his impossible to answer each and every commu- vices work. Some other magazines are full of moon, his landing on the moon and we to do our and of some alleged of earth from the moon. nication that comes in, but try photos of ingenious devices views the best. designers of same, but with no rational explana- suggestions in order: tion of the scientific basis. Some of your minor LAKH-DAL, DESTROYER OF SOULS, Taking your queries and some by W. F. Hammond. Here is a story that 1. The Edison effect, the two electrode vacuum departments havé contained (in small print) of gas engines and steam en- wonderfully clear and succinct explanation. I contains good science, thrilling episodes tube, new styles and tense situations and will remain a gines, as well as the Hall effect, have all been noted some very excellent work at times in your of AND IN- and in your "Patent Advice." The vivid memory for many years to come. If described in past issues SCIENCE "Radio Oracle to nightmares, VENTION in rather full detail. subjects of television and allied branches have you are at all addicted How and as a magazine don't read this story at bedtime. 2. In the series of articles on The been excellently dealt with, as far Why of Radio, subsequently published in book of your scope can go. WORLD (a -carbon, elec- that you are a com- THE MASTER OF THE form, the crystal Audion, mercury The Knife. I recognize Serial in Two Parts) Part II, by Jules trolytic, magnetic, dry electrolytic, Bunsen mercial proposition and that after hearing from styles were not only from me, you have to Verne. In this installment, the uncanny burner detectors and various other all your readers, appearances and disappearances of the described. Of course, it would be of no particu- decide what will best sell your wares, but still I safety resumé which if you have not at times deserted your mysterious thing that threatens the lar value to republish a historical wonder of the world continue, until Strock, the had already been published in back issues of best field in a short-sighted attempt to get immediate detective, circulation, instead of looking to a steady future Inspector of the Police and head this magazine. solves the mystery in an extremely unex- 3. Unfortunately, very little can be done with with permanently attached readers. in radio, while its elimination I think there must be a large and principally pected manner. static electricity field along the lines of your old Experi- from radio would be a valuable asset. unworked And others. 4. Dry piles have been described. The current menter on a wider scale. There must be (in fact due are) millions of men and women interested which they produce is so short in duration, there to polarization exhaustion and the constructional in science and its results and methods who deserve worthless up-to-date information on devices and principles. cost so great, as to make such batteries and many of these are in the class of amateur in the radio field. 3. Is not static electricity too much neglected 5. This is a hopeless quest. It would be im- inventors, who want information as to the prior be done state of the art and as to unutilized phenomena. these days? Could not interesting work possible for any publication to give the present Suggestions. There is, of course, a field for with it in radio? state of art on any subject and cover the patent 4. Dry piles (Zamboni) could these be used, situation on the same subject. The U. S. Patent "wonder," viz., the statement of great achievements in place for us to marvel. at and admire, but a little of with suitable resistances for voltage drop, Office has issued nearly two million patents, but do not get excited, of "C" or "B" batteries? what they cover cannot be told by even an ex- this goes a long way. We really of art" For we amateurs, until we can reasonably imagine 5. Wanted-articles on "present state perienced attorney, prior to court litigation. ourselves doing the work. That is why radio, at in each branch so that the amateur inventor can instance, Dr. deForest thought that he was the now television, know what has preceded him even though obsolete, inventor of the Audion, or three electrode vacuum which everyone could tinker, and and money in him; and have so great an appeal and also why, I venture to so that he shall not waste time tube. Later the courts decided against reinventing. still later have decided in his favor. bet, radio will fall off in popular favor; viz., be- electro- cause the achievement of any results in it, is 6. Radio waves are electro -static and 6. Transmitters have no effect on local or ter- amateur's powers. One magnetic from different viewpoints at any given restrial magnetism. Subantennas are successful, rapidly getting beyond the Does a transmit- is therefore driven back upon substitutions, viz., moment, the earth is a magnet. but not for this reason. ter cause fluctuations, possibly locally limited, in 7. The distance between the antenna and the cheaper home devices for expensive factory ones, subantennas effect in the trans- or into little explored corners (see success of terrestrial magnetism and is this why ground has of course quite an an amateur are successful? mission of radio messages. The smaller the dis- amateurs in short wave work) wherein so amount may possibly stumble on something novel. To us 7. Antenna and ground-are they essentially tance, the shorter the range with the same is an different-the antenna is a conductor plunged in of power and at the same wavelength. Short amateurs, reliability as well' as clearness, in the with a asset. the air and the ground, a conductor plunged waves seem to carry exceptionally well The amateur lacks knowledge, he needs a "club- earth which is in contact with the air and mag- minimum amount of power. In this case, an- bable" kind of paper to which he can submit his netically one with it. May the true difference tenna and counterpoise are generally quite close not be the distance between them; i.e., that two to each other. half-baked ideas and get help and information with- Is out being made to feel that he is an intruder. You antennas or two grounds distant an appreciable 8. Transmission of earth waves done in the fraction of a wavelength from one another are case of submarines and likewise in the case of have the friendly cordial manner for that and you or antennas, so suc- have the knowledge or at least access to it. receiving when the waves are in different phase sub -antennas underground (at least partly different)-the most powerful effect cessfully demonstrated during the war by Dr. Personally you are slaying the slain for nie Rogers. when you tackle astrology, second sight mediums, would he between conductors plunged at points half James Harris a fight a wavelength apart (obvious precautions in experi- 9. The suggestion advanced in your ninth etc., but I grant that human nature loves is itself is possible. The difficulty is in producing or to read controversy within reasonable limits. ment needed as the intermediate conductor query and condenser.) a reflector which would cut off the radio waves Your Ionaco articles, etc., are excellent from that an aerial to pass rapidly enough at viewpoint and there is a field there capable of 8. Proceeding on the idea of No. 6 above, has and then permit them it been tried to discard "aerial" transmission, and a speed capable of modulating the wave. Mov- expansion by one applying psychology to editor- a new idea ship, as your editor does, though with certain to devote attention to producing earth waves. Not ing the reflector around is not and this to supplant the present system, an article on this subject appeared in past issues lapses. that I suggest reflectors Herewith are a bundle of semi -scientific sug- but merely for experiment. of this magazine, where moving were 9. Given a source of light waves, unvarying, used for directive or beam transmission at light- gestions or queries: house 1. The amateur inventor comes in the second one can modulate same for signal purposes with stations.-EDITOR.) 1014 Science and Invention for March, 1928

REC I PES SZ FORMULAS Edíted by S. Gernsback

PUSH PINS SNOW CLEANER FOR AUTO TOPS CAMP OVEN goush SEALING A handy ' MAT WAX pVery pins TACKED ON CASING -INNER UPPER can be made camp oven NEEDLE LID LID ' b y dipping can be made by taking an 1i 0 1 d phono - _\-----__O o o o 00000 1 tir graph nee ------o d bucket dlesinto ell--- 'Il /- with a lid ''T uV a n d insert- BREAD WAX molten seal - i, j18? IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII111111111111IIIIII1111111111IIIIIIIIIIIHN¡A11I' i6 ing wax. ing a small- DOUGH They are er lid into COALS I dipped sev- it, about one-half the GUN eral times to w a y SHELL make a large V III head, which il; Grease t h e ii`:".: ì!`->_- may be 'Alli THIS DISTANCE ii_ lid PHONOGRAPH NEEDLES - and set the molded with _+? SHOULD BE LESS Vim t h e fingers 8" improvised baker Wÿa,°Q in various shapes before the wax hardens. An -,it1'II THAN THE ACTUAL Il'"- upon .rrx-ts empty shell, filled with wax, qll1d a pilecoalso f `CROSS SECTION OF CAMP OVEN with a needle in- HEIGHT iuPl'4 serted as shown, also makes an excellent push OF THE w arm iI and place pin. Small -headed pins of various colors used to P1 i'F AUTOMOBILE If others about the sides. Agate or tin - ON- buckets may be used mark maps and charts may also be made in this !Ill1 very nicely-Amos Roberts manner.-D. S. Jenkins. - Sweet. l l'; SPINNING COIN Nil p TEST TUBE If a stream GARAGE 0QDRWAY HOLDER of com- TO COMPRESSED AIR TANK ,Arl' pressed a i r Old battery is played A strip of an old mat about 16 inches in width clamps which COIN can be easily made into a cleaner for automobile upon a spin- tops. TEETH EATEN eg coin, A number of slits are cut in one side of discarded be the coin will the mat and should be about 3 inches deep. The OFF BY ACICcause their mat is tacked on the casing of the garage door, teeth h a v e be kept not eight inches less within t h e than the height of the become eaten range of the auto.-Fred White. /\ away by stream a n d acid, make will appear excellent to spin of its test tube own accord, - FLOWER EXPERIMENTS holders f o r creating a ''BATTERY ELI, the labora- very puzzling and interesting effect. The coin is tory, as given an initial shown in spin with the fingers and con- the illustration. The clamps may also be used tinues to spin as long as the compressed air is for many other purposes in the experimenters' directed upon it.-W. F. Crist. fie laboratory, j -1_ '`.%k and the spring on the clamp will provide enough tension to hold all apparatus tightly,-Miner REPAIRING PIPE STEMS lW O M. Horneen. Empty rifle ¡CUT HERE; a n d pistol CRIMSON DAHLIA PURPLE COLUMBINE cartridges CHANGES TO YELLOW CHANGES PINK á BLACK CRACK are extreme- SIMPLE LOCK NUT ly handy A simple around t h e lock nut FILE HERE RA/BREADS jFERRULE shop or arr a ngement home work- can be made VI Ea an bench. They as shown in O I.P MeNWPI ®lEGÍÌli are available the illustra- V in sizes up tion. The to one - half O end of the L.H. THREADS inch in di - BROWN STREAK bolt is filed FERRULE ameter and moo m111111111'. 'YELLOW REMAINS IN WALLFLOWER until the ex- 11U 43 make excel- UNCHANGED IS DISCHARGED tending por- -- lent ferrules and reenforcing bands for small re- tion is of a standard smaller size. This portion is pair jobs on split canes, cracked pipe stems and now cut with left-hand threads. The tendency the like. They may be polished, plated, or Many interesting experiments can be carried out for the larger nut to turn will tighten the smaller finished in any way desired. The cartridges also with the aid of flowers and crimson one as both nuts turn in opposite directions. have sufficient to matches. A The strength withstand all ordinary dahlia held over a match changes to a perfect bolt should first be screwed in position, so that usage which is given to small articles. The illus- yellow. A purple columbine changes to pink and one can find out just how far to cut the left-hand tration shows how a cracked pipe stem may be then to black. Other experiments appear in the threads. The smaller nut should fit snugly repaired.-Edwin D. Morwin. illustration.-Vernon Miller. against the larger one.-T. F. Maher.

ETHER EVAPORATING METHODS IRON H250 DISH OF TESTING MILK CHLORIDE In order to test milk for boracic acid, evaporate a small quantity and incinerate the residue. Add hydrochloric acid and dip tumeric paper into the solution. H2S0ß HYDROCHLORIC If the paper is stained red, boric acid is present. After the _i -MILK. ACID milk has been evaporated, the residue may be treated with hydrochloric acid for the detection of carbonates. Boiling the milk with hydrochloric H2SOciee Yet acid and iron chloride is a good test for formalin. If milk is shaken with ether and the ether solution evaporated, a test for salicylic acid can be ETHER FIG. I HYDROCHLORIC FIG. 4 Above-testing for boracic acid. HYDROCHLORIC ACID Testing for salicylic acid. ACID FeCI made. Alcohol and iron chloride besides salicylic acid produces an are added and a violet color is dis- intense bluish - violet coloration. cernable if this acid is present. The When adding a small portion of drawing shows the procedure for salicylic acid with some concen- making the test. The milk should trated sulphuric acid and then be underlayed with sulphuric acid dropping in methyl alcohol continu- containing a trace of iron chloride. ously and heating the mixture to A violet -blue zone will form if FIG. 3 boiling, an odor of oil of winter- formalin is present. Ferric chloride FIG 2 green is produced. Milk should be when added to an aqueous solution Testing for carbonates. Testing for formalin. free from preservatives. Joe Sill. Science and Invention for March, 192d 1015

Ra(liO Guides Torpedo Joat By LUCIEN FOURNIER

At the left we have a a special detector. Next to this was placed photograph of the scout radio system. A spe- boat on the Seine River, the remainder of the in France. The craft was cial rectifier, following the radio receivers, controlled by radio en- supplied a direct current capable of operating tirely. Note the antenna circuit strung above the boat a sensitive relay which closed the for the reception of the upon reception of signals from the shore. controlling radio waves. All the apparatus was enclosed in a metal The boat was guided without anyone on board. box or shield. Along with this arrangement, which forms the radio electric equipment of the receiving systems have been Below is a photograph set on the boat, various showing the boat on the adapted to control the motors. For start- bank of the river ready ing the motors, an apparatus is used which for launching. Some idea of and compressed of its size may be ob- sends a charge carbureted tained from this photo- air into certain cylinders of each motor. graph. The antenna This carbureted anti compressed air is kept masts are shown clearly 18 pounds in this view. The aerial at a constant pressure of about has not yet been put in by the action of a little compressing mech- place but is shown coiled anism which starts automatically. The con- on the deck. trol is done by the operation of a relay which opens the valve and then operates a second relay which closes the "make and break cir- THE idea of control- cuits," and consequently ling a boat entirely explodes the mixture in a new by radio is not the cylinders of the mo- one and has been tried The first relay is the tor. out many times in operated by sending sig- past. However, it is nals which represent the the claimed that this is command " forward." first time that radio Commands "faster" and control has actually "slower" direct the been proven to be suc- speed of rotation of the cessful, insofar as all motors. The radio sig- the movements of the nals also bring an elec- craft were under con- motor into action Re- tric trol at all times. which operates the cently, on the Seine choke valve of the car- River, in Paris, a tor- buretor, whose action is pedo boat, shown in the limited by contact. A accompanying photo- projector sends a beam graph, was completely into the air and the of light controlled from is operated by six im- transmits ing station on pulses from the trans- the shore. An antenna Another motor on the mitter. was installed is provided which steers boat, and connected to a the boat to the right or receiving set, which to the left. During consisted of three stages war time, in order to of radio frequency and

- E CTRIC MOTOR RJDDER GOVERiÌtÌ+ti-SPF.D-.,d.. CO NTROL SWITCHBOARD Al) TC MATIC CON MUTA7-pla.

Above, the controlling apparatus is shown, and has been marked upon the photo. Above, the 2 Hispano -Suiza motors of 180 H.P. each, for propelling the boat. 1016 Science and Invention for March, 1928

circumvent any subterfuge which may movements. The electric motor gov- be used by the enemy, the radio com- erning the speed, the switchboard, mand can be effected in two parts, rudder control and automatic com- which may be termed the "prepara- mutator. The The transmitter controlling tion" and the "execution." the movements of the boat, "preparation" consists of a number of operated impulses separated by a cgrtain de- on a wavelength of 300 to 500 meters. gree of time. These may actuate re- For operating the boat automatically lays and the like, and so prepare the during the night, a projector, consist- receiving apparatus for the reception ing of a 300 -watt lamp was installed of the next signal giving the actual in the bow of the boat, and was con- command. The action can then be trolled by radio from the shore. In stopped in the same manner. The the interior of the boat were a number signals, of course, can be made as of storage batteries of 40 volts each, varied as possible, using numerous rated at 40 -ampere hour capacity, and combinations of dots and dashes and a 500 -watt generator which was oper- different intervals of time. In order ated by the propelling motors. The to make the boat proceed at a cer- boat was invented by M. Chauveau, tain angle, the radio operator can do engineer of the French Radio Elec- this bit by bit, until the correct angle tric Society, who has also devised a is reached, thus obtaining better con- means of launching torpedoes from trol. The boat mentioned here was the boat by using the radio controlling controlled by means of a portable system. The apparatus for complete radio transmitter installed in an auto- radio control is of elaborate design, mobile on the banks of the river. and even the smallest movement can Both the transmitter and antenna may be directed from the transmitter on be seen in the photograph. The boat shore. At a given signal, the boat itself was propelled by two Hispano - starts, stops, reverses, turns around, Suiza motors of 180 horsepower each. or goes to the right or left, at the These motors may be seen in the will of the radio operator. The pilot photograph appearing here. A view and the rest of the crew have been of the right side of the boat also dispensed with, and we may see the Above is a view of the automobile radio transmission station appears and shows the grouping of which was erected on the edge of the Seine for controlling the use of radio -controlled boats in the the apparatus for controlling its movements of the boat. next war.

Making a Remote Control Switch By ELMER J. GARBELLA

since, as seen in Fig. 3, the armature is top 1 S. P. D. T heavy and after being pulled over by the Fi p.2. ELECTRO To99Ie A. MAGNET. Fig'.1 magnet will remain in place, making good Switch contact due the spring, C to without further ARMATURE application of the current. Secondly, the 5.P.D.T. 4 BATTER? electro -magnets can be located within the 'O radio cabinet, and the filament switch is thus 111111 5WITCH,A. SWITCH D not far removed from the rest of the apparatus. Short leads are always desirable Above is a toggle switch that can be easily in a radio receiver and thus it is best to made by anyone. It is of the single -pole, (73TO RADIO SET E keep the filament switch within the set double -throw type. 2 itself. Although the lines to switch A may cover a considerable distance, it will be noted that there is no steady current passing also to the other pole on the toggle switch. through them, as there would be if the fila- Binding post No. 3 connects to the other Fig. 1, above, shows the hook-up of the com- ment switch were thus far removed. In ends of the electro -magnets, and also to the pleted remote control switch described here. Fig. 3, binding posts 4 and 5 are the only two "A" battery. The armature is connected to which are connected to the radio receiver. binding post No. 4 and the spring to binding post No. 5. blade Binding post No. 1 is connected to one end The of the toggle switch P-1-` HE contrivance shown here is not an of the electro -magnet C and also to one of is connected to the other side of the "A" absolute necessity, but the radio fan the poles on the single -pole, double -throw battery. The toggle switch A can easily be who likes to tune in a good program and toggle switch. Binding post No. 2 is con- macle from two metal angles and a switch then retire and listen in, will find that it nected to one end of electro -magnet E and blade made from a piece of metal with an makes things a great deal easier. It is insulated knob, as shown in Fig. 2. The rather irksome to have to get up and turn armature should be made from a piece of off the filament switch of the set in order soft iron and weighted at the top, so that to stop the radio. Fig. 1 shows the hook-up it will stay in position after being pulled of the arrangement. Fig. 2 shows the con- SPRING Fig. 3 over by the magnet. As will be seen, one struction of a small single -pole double -throw end of the core of each of the electro -mag- toggle switch, and Fig. 3 shows the electro- nets is cut at an angle since the armature magnets which take care of the filament moves through an arc. Electro -magnets current switch. When, by means of the ARMATURE suitable for use in the remote control switch single -pole, double -throw may be obtained from an old bell. switch, the battery C door If current is sent through the electro -magnet none are available, they may be made by E, the armature is pulled over so that a winding approximately 150 turns of No. 28 contact is made. When switch A is thrown wire on a soft iron core about one -quarter to the opposite side, the battery current is inch in thickness and about an inch and one- sent through electro -magnet C, pulling the half long. The diagrams and the accom- armature to the other side, thus breaking panying text should make the construction the contact. It will be seen that binding of the remote control switch clear, and one posts 4 and 5 form a single -pole, single - should have no difficulty in making it. The throw switch by using the armature. Fur- switch should cost next to nothing, as most thermore, the toggle switch controls the of the parts will be found in the experi- armature, and therefore also controls the menter's junk box, or can be made as de- switching of posts 4 and 5. After looking scribed. The arrangement is simple in opera- over the diagram, the advantage of this tion and only one connection is made to the ro RADIO SET arrangement can easily be seen. In the radio set, namely, from the A -minus to post The above illustration shows the two electro- 4. first place, the battery used to run the re- magnets which take care of the filament cur- No. The negative "A" battery terminal mote control switch is not used constantly rent switch. connects to No. 5. Science and Invention for March, 1928 1017 NEW RADIO DEVICES Accessories Recently Developed Which Will Improve Any Radio Set

SHORT-WAVE ADAPTER FOUR -VOLT "A" ELIMINATOR NOVEL CONE SPEAKER the most unique speakers which A Milwaukee radio manufacturing com- 11O AC. VENT One of pany has recently brought out a short-wave we have seen in some time has been brought unit or adapter which can be used with any out by a New York manufacturer. Two receiver. No changes in wiring have to be large cloth cones made of airplane linen made and all tuning is done with the one SET suitably "doped" are stretched upon a square dial on the short-wave adapter. The de- wooden frame. Two of these frames are one tector tube is removed from the socket of 4VOLT Ä ELIMINATOR used and held together by four bolts, the receiver and placed in the adapter. The at each corner. The cones are drawn in short-wave unit plug is then fitted into the rather sharply at their mid portions. The detector socket as shown in the illustration. unit is supported by wood cross -sticks and The device is sensitive and capable of dupli- is placed as shown in the illustration. Ex- cating the results obtained with any short- cellent reproduction is obtained, especially The four -volt "A" eliminator is shown above on the low and high register. The drive rod wave receiver. The aerial and ground should connected to a receiving set using 199 -type be removed from the set and connected to tubes. is attached to the apex of each of the in - the aerial and ground clips on the short - Illustration courtesy Abox. Co.

For those having receivers employing 199 ,WOOD tubes, a Chicago manufacturer has put a FRAME four -volt "A" eliminator on the market. The eliminator is enclosed in a green metal case and operates entirely without any ob- DRIVE jectional hum. An electrolytic rectifier and ROD ADAPTER electrolytic condenser are used. In order to use the eliminator, it is only necessary to DET SOCKET UNIT attach two wires from the A- and the A+ BOLTS SHORT WAVE UNIT on the set, to the A- and the A+ on the eliminator, and then plug the unit into the UN IT 110 -volt A.C. lighting socket. It is inter- `SUPPORT The short-wave adapter is shown above hooked esting to note that the plates for the elec- to the receiving set. No changes in wiring are necessary, the unit simply being plugged trolytic condenser and electrolytic rectifier AIRPLANE into the detector socket. are immersed in the same solution. A vent CLOT H Illustration courtesy J -M-P Mfg. Co. is provided at the top for the escape of any CONES gas which may be generated while in use. wave unit. This adapter works- as a de- A handle is provided for convenient tector unit with all sets. The same instru- carrying. ment functions as an oscillator -detector unit Above we have a side view of the speaker with superheterodyne receivers, converting showing the placement of the unit and the into supers. The dials of two airplane linen cones. them short-wave inc. the set have no effect in tuning when the A.C. TUBE ADAPTER Illustrations courtesy Air -Cone Studios, short-wave unit is attached, therefore, they may be left at any setting. This unit is verted cones. The illustrations shown here not available with interchangeable coils, but AC. CONNECTIONS will give one an idea of the construction of may be obtained with them on special order this reproducer. The speaker will handle to cover other wavebands. plenty of volume without distorting and will produce all programs with equal fidelity. Another distinct advantage seems to lie in HOME BROADCASTING OUTFIT the fact that the speaker tends to reproduce A home broadcasting unit for use with the low notes without a falling off of any receiver employing audio frequency volume. The speaker is rather simple in amplification of some sort, has lately ap- design, is now available on the market and peared on the market and is made by a may be bought at quite a nominal cost. Al- Brooklyn manufacturer. The outfit consists though the speaker is rather large, it should of a microphone and a UX adapter for plug- look well in an ordinary sized room with- ging into the detector socket of the receiver, out being too conspicuous. There are many camouflage the speaker, so that the audio amplifier may be used to UX AC. TUBE ways in which to amplify any sounds which are picked up by such as under a table, etc. the microphone. Long leads are provided, ADAPTER so that the microphone may be used in an WOOD FRAM E A new U% A.C. tube adapter is shown above. adjoining room from the receiver. The A.C. connections are made to two lugs projecting from the sides. Illuviratio,, courtesy Alden Mfg. Co. MICROPHONE Many have hesitated to employ the new A.C. tubes because their use would necessitate the change of wiring within the receiver. In order to make A.C. conversion simple, a prominent New England manufacturer has developed an A.C. adapter. The ADAPTER A.C. tube is plugged into the adapter, which, FOR DET in turn, is plugged into the regular socket SOCKET on the radio receiver. The two filament prongs on the adapter are "dummies," the A.C. connections being made to two lugs which project from the side. The grid and plate prongs connect directly to those on the ordinary socket. By using this adapter, CORD CONNECTOR it is not necessary to change the present AIRPLANE CLOTH CONE filament wiring in the receiver, and the set may be readily converted to A.C. operation The front view of the speaker appears above. The home broadcasting device is shown above short time. The manufacturer The linen cone is tacked upon a square and consists of a microphone and an adapter within a for the detector socket. makes a complete set of these adapters for wooden frame. A bolt at each corner holds Illustration courtesy B -M -S Corp. any receiver. the speaker together. 1018 Science and Invention for March, 1928 THE LABORATORY

A Receiver of Efficient Design By PHILIP

chassis. All possible wiring should be done isolated from all other wiring and run under now without proceeding further. Leave free the chassis separately. the wire ends that will connect to the instruments on the front panel and to the two OPERATION audio transformers. This is necessary, be- With the "A" battery switch on, the rheo- cause if the audio transformers were stat should be turned almost to its full height mounted first, it would be impossible to make position. Now if the potentiometer knob is the connections to the output of the long - turned to the right, a "plunk" should be wave amplifier. After these connections are heard at some point. This knob should al- made, the audio -frequency transformers can ways be operated just to the left of this be mounted and connected, then the front "plunk" point. This adjustment should be panel may he prepared. The potentiometer made with the first detector tube out of its should be mounted as shown, using insulated socket. The first detector tube should now washers to thoroughly insulate its frame be inserted and the midget condenser set from the panel. The rheostat and midget with its plates all of the way out. The condensers are now placed upon the panel. antenna coil rotor should now be set at a The two drive mechanisms of the dials 45 -degree angle and the oscillator rotor all should now be fastened to the panel by means the way in. A small antenna of 30 to 50 of the two brackets furnished with them. feet in length should be used. A larger one One variable condenser may now be fastened may be used if the set is not too near some to either bracket. A drum should then be powerful local station. Signals from weak slipped over each condenser shaft. All wir- stations may be intensified by turning up ing should he clone with flexible hook-up the regeneration condenser on the front panel. wire. The connections to the condensers. ROTOR COIL ADJUSTMENTS rheostat, and potentiometer should be made The position of the antenna to the chassis. coil rotor before fastening the panel should generally be at about a 45 -degree The on and off switch is mounted in the angle. in- With a small antenna, it may work A photograph of the completed super together hole provided for it, and is thoroughly best all in, with a large antenna at nearly with its loud speaker appears above. Note sulated from the panel and chassis. the artistic appearance which is afforded by right angles. The sharpness of tuning of the metal cabinet. WIRING THE RECEIVER the antenna dial depends upon the setting of this rotor, as well as that of the midget THE receiver shown on this page em- As mentioned before, all wiring should be condenser. The oscillator rotor should he ploys the superheterodyne circuit, ac- done with flexible hook-up wire, and con- adjusted once on a very weak signal at about knowledged as the most sensitive and nections should be soldered to lugs or fast- 300 to 350 meters, and once set for maxi- the most selective. The shielded ened under binding post screws where mum volume, may be left alone. super has great distance -getting WAVELENGTH RANGES ability and at the same time is very easily tuned. Probably the The actual wavelength range most important feature of this set of this super is from 30 to 3,000 is the handling of the intermedi- meters. This range is covered by ate frequency amplifier. Here a set of five plug-in oscillator and use is made of a time -signal am- antenna coils. On the shorter plifier made particularly for the wavelengths, amateur and short- jewelry trade to receive time sig- wave radio stations may be heard. nals that are broadcast daily from POWER AMPLIFICATION Arlington, Station NAA. This unit consists of three stages of It is highly desirable that au radio -frequency amplification and output transformer be used be- a detector, and is sharply tuned tween the speaker and the re- to Arlington wavelength, 112 ceiver when a power tube is used. K.C., so that only one station can This unit has not been included in be received at a time. This time - the set since the ideal way to signal amplifier is completely Above is top view: Tops of the shields have been removed, showing the build it is to leave out the sec- entirely two tuning condensers and the antenna and oscillator couplers. ond audio stage entirely and use wired in the factory, Photo courtesy Silver Marshall shielded by individual stage com- a power amplifier of some kind. partments, enclosed in a brass If this arrangement is used, both and copper catacomb, and the whole unit practical. A fter testing, all wiring may be audio tubes and one audio transformer can tuned sharply to pass one band of frequencies bunched and laced into neat cables. How- be left out of the receiver proper, and the only. This outstanding unit may be termed ever, there are two leads which especially two output leads from this transformer sec- the backbone of the circuit. should not be included in the cables. These ondary then lead to the power amplifier or are the wires running from the detector power pack. There is room in the set LAYOUT OF PARTS stage along the bottom of the chassis up to for the incorporation of an output trans- The detector and oscillator assemblies the oscillator coil. They should be well - former. should be mounted upon the chassis inside the stage shield pans. The grid condenser and choke coil are also mounted in the de- At the left is a bird's- binding posts are eye view of the super tector assembly. The with tubes in place. The mounted in the rear and the ground post time -signal amplifier is grounds to the metal chassis. The four -tip placed at the rear of the the right base to the left. The jacks should then be mounted at two audio transformers rear of the base. The intermediate frequency are mounted next to this. is then mounted. The A- con- Nine binding posts have amplifier been placed along the nection is automatically made to the ampli- rear edge of the base, in fier through the contact between the ampli- back of the time -signal metal chassis, no other amplifier. The two drum fier shield and the controls are used for A- connection need go to the long -wave tuning the oscillator- and amplifier. The two audio amplifier tube antenna - coupler c o n - using their densers. The midget con- sockets should now be mounted, denser, three -ohm rheo- rear fastening screws as a means of con- stat, and the potentiom- necting the F-posts to the chassis. The eter are placed between fastening screw of the ground post holds the two drum dials. one end of the /-mf. fixed condenser to the Science and Invention for March, 1928 1019 SHIELDED SUPER Easily Built and Entirely Shielded RADWELSKY

1100075 MF. R.F. CHOKE 2ZMILLIHENRIES

.000 35 MF

OSCILLATOR ANTENNA COUPLER P..- t COUPLER G .00015 ME

TIME SIGNAL AMPLIFIER + B+ lib P G P G

Above we have the picture diagram of the shielded laboratory super, the A jeweler's time -signal amplifier is used for the intermediate frequency construction of which is described in the accompanying text. . stages. It can be obtained completely assembled.

TUNING FOR DISTANT STATIONS wavelength within seven to ten kilocycles of 4 tip jacks. In tuning for distant stations, the two powerful local station waves. On short 1 2-megohm grid leak. drum dials should be varied to receive a waves below 200 meters, the receiving range 2 audio -frequency transformers. signal and the midget regeneration condenser is unusual, and great distances may some- 4 cushion sockets. set with the plates about one -quarter the times be covered. The two illuminated ver- 2 vernier drum dials. way in. In order to cover the entire broad- nier drum dials do all the tuning, with three 1 21/2 -millihenry R.F. choke. cast band, the antenna dial should be varied additional non -critical controls. 2 .00035-mf. variable condensers. 1 time in steps of about one degree at a time, and THE CABINET -signal amplifier, or other intermedi- for each of these one degree steps, the The completed receiver may be housed ate amplifier peaked at 112 K.C. oscillator should be varied over a range of within a metal cabinet such as that shown 2 plug-in coils with sockets. fifteen degrees above and below the antenna here or may be put in a -console of a design 9 binding posts. dial setting. Once a weak station is heard, and richness limited only by the owner's 1 midget condenser, maximum capacity it may be strengthened by turning the midget pocketbook. .000075 mf. condenser further in and resetting the an- LIST OF PARTS 2 stage shields Names of manufacturers of parts fur - tenna dial slightly. If stations are heard 1 Metal panel and chassis unit or metal on two or more points on the antenna dial, cabinet. Wished free upon request. it is not the fault of the receiver, but is 1 .00015-mf. grid condenser with grid leak TOOL LIST probably due to reradiation of transmitted clips. Pliers, several kinds. signals from local steel structures and the 1 200 -ohm potentiometer. Screw -drivers, several sizes. like. The shielded super is extremely sen- 2 1/2-mf. by-pass condensers. Hammer, hacksaw and blades. sitive and is selective enough to allow re- 1 3 -ohm rheostat. Hand drill. Electric soldering iron. ception of out of town stations, using a I battery switch. Twist drills, several sizes. R.FCHOKE METAL SHIELDS 075MF- 31LLIHENRIES--i-OSCILLATOR COUPLER TIME SIGNAL AMPLIFIER. --5

1 i I TYPE 2MEG .Ie'iMF. TYPE UX 201-A TYPE t OR UX 240 UX 171 i. IÍo TYPE UX 201-A .00035 MF I TYPE TYPE UX2ohAI UX201-A UX201-A OR UX 240 ó r

.00015MF II 00035MF ' TYPE U X 201-A J lI3 1MF. .002MFi- ANTENNA TYPE COUPLER UX201-A rr J J

200 -OHM q

HI iME1 133GHM I

ANT GRD. A -B -C+ A+ C-DET C -AMP. B+45 B+ 90 B+ AMP. The schematic diagram showing the hook-up of parts is shown above. A radio -frequency choke of 2V, millihenries is connected in the plate cir- Both the oscillator and antenna couplers, together with their tubes and cuit of the first detector. A power tube of the UX-17l type is used in the condensers, are enclosed in metal shields, as shown in the photos. last audio stage, providing plenty of handling capacity. 10.20 Science and Invention for March, 1928 S & I. 3 -TUBE A.C.---D.C. SET By PAUL WELKER The Second Part of an Article Describing the Construction of a Versatile Receiver for Battery or A.C. Operation How the Set Is Adapted for A.C. Tubes

Above is a photograph showing the layout of parts in the receiver. Note that the A.C. transformer has been placed on the right side of the sub - panel, away from the three -circuit tuner.

IT will be remembered by our readers that C -plus amplifier and the first part of an article describing the B -minus power are construction of a receiver, for A.C. or A bottom view of the set appears above, showing how the wires are connected to the brought out in cable form and the twisted pair leading up to the A.C. battery operation appeared in the February ground, as is the C - transformer. issue of this magazine. This, the second minus detector lead. part of the article, will deal with the con- Outside of the slight version of the receiver for A.C. tube opera- changes mentioned -above, the circuit re- and C leads, as there is less danger of get- tion. By changing a few wires, the receiver mains the same and can be easily converted ting these mixed. is ready for use with A.C. tubes. The tubes for A.C. operation within a short time. A The set usually works satisfactorily when used had a standard four -prong, CX base, cable should preferably be used for the B using the light circuit as the antenna. This may be done by connecting a condenser having a capacity of about .002 mf. between one Li, side of the lighting line and the aerial bind- OUTPUT IMPEDANCE ing post on the receiver, the outside antenna 2MEG. VOLUME being detached. CONTROL / For those who have not built the D.C. receiver, it may be ill to mention that a aó L,/ zTrif small three -circuit tuner was employed which 0 á will cover the broadcast wavelength band 001 CD when tuned with a .0005-mf. variable con- -mf CD <> denser. Since a power tube is used in the i J last stage, in both the A.C. and the D.C. -o set, an output transformer or output impedance will have to be employed. . LIST OF PARTS á >I > 1 small 3 -circuit tuner o 1 .0005-mf. variable condenser 3 cushion sockets 2 low -ratio audio -frequency transformers 1 output transformer or output impedance 1 zero to 500,000 -ohm variable resistance o 1 midget jack DET.0+4z-9V C+ AMP C- 'C- PWR B+DEL 'B+AMP B+PWR 1 power switch 5'-PWP AMP 90-135V 135-160V 3 A.C. tubes (detector, amplifier and power tube) 1 A.C. transformer for type tubes used The schematic diagram of the 3 -tube A.C. receiver appears above. The "C-" detector is connected 1 2-megohm grid leak to the "B-" power and "C+" amplifier, which ultimately go to the ground. Note that the con- 1 2-mf. speaker filter condenser (if output im- nections of the grid leak are changed slightly and that one end of the leak is connected to the pedance is used) "C+," in order to obtain a positive bias for the detector tube. 1 .001-mf. and 1 .00025-mf. fixed condenser

and operated on 15 volts A.C., taking .35 I I amperes each. As the construction was completely described in the previous issue, it will not be dealt with here. A.C. CONVERSION First of all, the A.C. transformer should be mounted on the baseboard at the right. and kept away from the tuning coil and other apparatus, as far as possible. As the filament wiring has already been cabled, it is only necessary to attach the two leads which originally went to the "A" battery, to the secondary of the A.C. transformer. The grid leak connection will have to he modified somewhat, as shown in the accompanying diagram. One end connects directly to the grid of the tube and the other to the detector "C" battery, which provides a positive bias. The filament switch already installed on the panel may be replaced by a midget 110 -volt o o 0 o v d b o power switch, should be connected in C4 AMP T. which C+ DE C- AMP "C=PWR. -B+AMP. "B+PWR. El PWR. series with the A.C. line. The present fila- 42-9y. DET. 90-135V. 135-180V. ment switch, if it is of good construction, Above we have a picture diagram of the receiver which is identical to the schematic, and has been may be used for this purpose, however. Tin: printed here for the benefit of those who find difficulty in following the latter. 1021 Science and Invention for March, 1928 RADIO ORACLE we feel are of interest to the novice and amateur. Letters addressed In this department we publish questions and answers which answer is desired. to this department cannot be answered free. A charge of 50c. is made for all questions where a personal IN RADIO SETS HORN When the open circuit voltage is between 130 SHIELDING EXPONENTIAL the glow tube and 220 volts, insert in series with Center, L. I., (609) A. V. Herbert, IIackensack, N. J., writes: fixed resistor of 980 to 1,000 ohms between the (613) E. R. Flynn, Rockville a and the N. Y., asks: Q. 1. If possible, will you kindly illustrate in 90 -volt positive terminal of the eliminator a ex- plus terminal of the socket. When the Q. 1. What is the advantage of using shields your columns, the construction of foldéd filament no may be ponential horn similar to those developed by the open circuit voltage is less than 100 volts, in radio receivers and what materials of glow tube will function. used for this purpose? American Telephone and Telegraph Company, type radio of about 64 cycles. A. 1. Shielding has become popular with having a cut-off frequency use of intelligent shielding, 1. On this page you will find illustrated the OF SELECTIVITY set builders. By the A. LACK receivers can be made more sensitive than would plans for this horn, showing the layout of the advantage baseboard and central portion. All dimensions (611) C. L. Angstrom, Freeport, Ill., asks: otherwise be possible. Primarily, the The the chief causes for of shielding is to reduce the feed-back or to have been marked upon the illustration. Q. 1. Briefly, what are self -oscillation so that in- heaviest pieces of timber required are those for lack of selectivity in the radio receiver? advance the point of lack of selectivity creased amplification may be obtained. In this the heart -shaped blocks. Single blocks of timber A. 1. The chief causes for receivers far more of this size are usually not readily obtainable, may be divided into three main classes. The way, it is possible to make that introduce sensitive and capable of receiving over greater and they will, in most cases, have to be built up first class contains all the faults is the only reli- from whatever wood is obtainable, the lamina- excessive resistance in the radio circuit. Re- distances. At present, shielding lowest possible able method of definitely limiting the extent of tions being carefully glued and screwed together. ducing this resistance to the and electro -static The principal requirement is that the inner walls value will not only increase the selectivity, but the external electro -magnetic sensitivity fields between coils. By using shielding and thus of the sound channels be as smooth and correctly at the same time, will multiply the it is pos- For this reason the use of of the receiver. The second class of advancing the point of self -oscillation, shaped as possible. and volume number of radio - hard wood is preferable, so that the inner walls faults includes mistakes in coupling between sible to employ a greater loosening the frequency stages without undue difficulty in pre- can be polished after using a grain filler, thus the various circuits. Usually, Grounded making the air resistance of the surface as low coupling between any two of the radio -frequency venting or controling self -oscillation. assembly selectivity. Too loose rotor variable condensers have made receivers as possible. Throughout the entire circuits will increase the capacity effect, but in some re- a coupling will reduce the sensitivity of the free from body 3- of ceivers, especially on short wavelengths, this receiver. The third class includes the faults Thorough poor proportion between inductance and capacity annoying action is still experienced. the antenna circuit. shielding will eliminate this trouble entirely. in the tuned circuits and in between the body and the Many, non -selective receivers have too little induct- Changes in the field the ratio of interior of the receiver which may be caused by ance in their circuits. Increasing away from to capacity will improve the sensi- moving the hand or body toward or inductance will not influence tuning if shielding tivity and selectivity. The effect of shock ex- the panel stray from nearby broadcasters whose signals is used. A good conductor will dissipate citation be or currents more easily than a poor one. tend to blanket all other reception may charges very greatly reduced by the use of proper shielding Since copper has a low resistivity, it is a tuning the antenna circuit. efficient shield. Experiments have shown that or by strong magnetic fields will pass through very thin sheet metal. Any opening in the shield will SHORT WAVE CONVERTER entirely ruin the effect of the shielding material. its numerous J. Rondeau, St. Louis, Mo., asks: Present day broadcasting, with (612) and powerful stations, requires perfect magnetic Q. 1. Will you kindly publish a diagram for a plates have I can use with my insulation. In some cases aluminum short-wave converter which been used between adjacent radio -frequency present 5 -tube receiver. The short-wave coil sec- fairly variable con- stages, and while they serve the purpose ondary is tuned by a .00025-mf. well, they do not provide the full insulation that denser. the short- complete box shields of aluminum or copper do. A. 1. For those who wish to explore be used for shielding, but is not 125 meters, several ways Brass may also wave band from 15 to as good as copper or aluminum. Iron or steel are provided. However, most of them require the high -frequency of the present receiver must never be used for shielding changing of connections currents or circuits. Iron and steel have a high over to a short-wave set. In order to eliminate and will not converter may be built, resistance as compared with copper, q FT. this change, a short-wave readily the energy from field lines of the diagram of which appears upon this page. absorb mag- the receiving set nor force. Furthermore, iron and steel introduce The above diagram gives the constructional No change is necessary in effects and then have fields of their own are any of the battery connections disturbed. To netic If details of an exponential horn 12 feet long, necessary to dis- which would make matters worse than ever. having a cut-off frequency of 64 cycles. convert the receiver, it is only frequencies are to be shielded, the shields connect the aerial and ground wires and attach audio at An adapter will have to be thicker than those effective them to the short-wave converter. A thin shield is effective at care should be taken to see that all parts are made from an old tube base and the wires radio frequencies. cut accurately, so that the shape of the sound can be corre- high frequencies, because these short waves do marked P, A+ and A- connected to the any shield as readily as the channels will not be distorted and so that no on the tube base. The detector not go through cracks are left between the blocks. The unit sponding prongs lower frequency waves. A thickness of metal, from tube should be removed from the receiver and may be used satisfactorily itself is placed at the back of the horn. The in the converter. The plug from the No. 6 to No. 30 gauge completed horn is twelve feet long and has a placed socket for shielding. converter is then fitted into the detector to build a perfect shield be- mouth four feet square. The plywood sides set. The tuning is all done It is impossible should be screwed to the wooden blocks. During of the receiving cause any metal used for this work will have from the one dial on the converter. The tuning therefore could not absorb the final assembly all parts should be glued to- receiver are not used. The con- some resistance and gether, under pressure, as well as screwed, so controls on the of all of the radiated lines of force. The fewer the verter is really a short-wave set consisting the more effective it will that there will be no danger of them moving out detector and a simple plug for openings in the shield, of place. The mouth of the finished horn may be a regenerative be. All joints in the shield should be crimped connecting to the audio end of the present re- length. To prevent the covered with wire gauze stretched over light is controlled by a 0 to and soldered their entire grill work, or the whole speaker may be fitted ceiver. Regeneration passage of any lines of force into a shield, the 500,000 -ohm variable resistance connected across copper into a console cabinet. Probably the best pos- condenser wires may enter and leave through bent with an horn is the plate and the tickler. A 00025-mf. The extent of capacity effects between sible unit for use exponential with a set of three short-wave coils. A tubes. the like the moving coil type, especially for high-po,3ered is used will be very the shield, coils, wiring, condensers and vernier dial is necessary, as tuning the shield is increased when any or all work; but the balanced armature type performs choke coil is important and must not within So very and almost any kind of a unit will sharp. The of these parts are placed close to the shield. well, be omitted. When by-passed with a .002 con- allow, the shield show an improvement in its performance when lead to be long far as space limitations will exponential denser, it will permit the plate be kept at least two inches away from connected to a properly designed to reach the receiver. If a choke coil should in the pre- horn. enough made by all shielded parts. The best results cannot be easily secured, one can be feed backs will be secured if the of No. 26 D.C.C. wire on a venting of are winding 100 turns with shields enclosing the radio -frequency stages GLOW TUBE CONNECTIONS wooden spool one-half inch in diameter and from all other circuits. inch core. allowed to be insulated (610) H. Lambourne, Rochester, New York, a one -quarter writes: Q. 1. Will you kindly tell me how I may connect a gas -filled glow tube to my present "B" eliminator? VARIABLE ,/ R. F. CHOKE A. 1. A tube of the type mentioned is designed 3 MEGS2 RESISTANCE 2z MILLIHENRIES as a voltage regulator for the 90-volt tap of the i "B" eliminator. Besides keeping the voltage constant, it also assists in smoothing out the fluctuations in the rectified current. It acts as a shunt of negative resistance on the plate supply, taking more or less load automatically as the voltage tends to rise or fall from changes of the / OP load in the plate supply circuit. The tube glows SEC, .00025 with an orange -colored light when in operation. MF. W Absence of this light indicates that it is not C>. --0+A tn the circuit C> functioning, and, generally, that "B" 002 MF has been overloaded or short-circuited; in this b H event the voltage impressed on the two terminals .00025 RHEO- sr is below that necessary for the gaseous glow dis- ME. charge. A standard socket is used, with the plate and grid connections left open. The negative filament post on the socket is connected to the negative terminal of the elimiator. When the open circuit or no-load voltage of the eliminator between the 90 -volt positive terminal and nega- PA tive terminal is above 100 volts and less than the 90-volt positive terminal of 130 volts, connect Above we have a schematic diagram of a short-wave converter which can be used in conjunction the eliminator to the filament plus on the socket. are necessary in the receiver itself when this unit is used. in the receiver. with any radio receiver. No changes 1022 Science and Invention for March, 1928 Scientific Humor THE SPIRIT OF SCIENCE ON THE LEVEL? A certain well-known expert in animal Q. E. D. HE: "I see they are going to make um- behavior has four He sends two FIRST PRIZE-$3.00 children. "I brellas square after this." of them to Sunday School every week and heard SHE: "What is the idea in making them keeps the other two for controls. Tom was hurt, it square?" W. Crosley. how did it ain't safe to leave them -R. happen ?" HE: "Because 'round."-Millard Stephenson. BRING A GUN "Well, d o you s e e that 'Hello! Is this the Telephone Company? ditch over NO -RYE Could you send one of your trouble shooters Toni : "I've had an idea milling around in here there ?" out right away?" "Yes." my head for some time now." "What's ?" ! Aged in as it the trouble "Well, he DON: "Huh the wood, "My wife."-John II. Spicer. didn't."-LI(kc were."-Jesslvn Hull. Blanco. A STOVE-A STOVE, MY UNWOUND KINGDOM .. . OH "Doing any- in radio SINCLAIR I THIS RADIO SET Sign thing for yourself h/Ari vELOUS CHEMISTRY PROFESSOR: "Mr. Dunn, will /Wiry A and hardware since that car hit RANGE ONav'i252 store window :- you tell us about the composition of babbitt?" UNPREPARED STUDENT: "I'm sorry, Pro - you ?" "This radio s e t "I'm taking a MAR - lessor, but I don't get time to read up on with this modern literature."-Gleason Pease. yeast for that V E L O U S 'run down' con- RANGE only WHO PICKS THE FIVES? dition." - H. P. $12.50 !" Sedgze'ick. T HOUGHT- JoHN (a new clerk in store) : "You say FUL WINDOW- these articles in this basket are five and ten SHOPPER: - "If cents. How can I tell them apart?" THE CAUSE they let me get a look at the stove that goes MR. JONES (proprietor) : "Oh, it's easy A chemist says that the first alcohol was with that radio, maybe I'd risk $12.50 on enough to do that. Whichever one the cus- distilled in Arabia, which may explain those the both of them."-I'Villiant Lernkin. tomer picks up is ten cents." nights.-Mrs. C. W. Tilden. -William Cook. HOW THIS DRESSING (Distressing) NOT ON TIME CUSTOMER: "I want a dress to put on PASSENGER: "When does the half -past five around the house." jokes published here are paid train leave ?" DUMB CLERK : "How big is the house, ALLfor at a rate of $1.00 each; $3.00 PORTER: "At five -thirty, suh." madam?"-William Cook. is paid for the best joke submitted PASSENGER: "Well, the City Hall clock each month. is twenty-seven minutes past, my watch is WHEN SHORT CIRCUITS ARE Jokes must have a scientific strain twenty-five past, and your clock is thirty- GOOD and should be original. two. Now, which one am I to go by?" FIRST MILKMAN : "The battery ill my car Write each joke on a separate sheet PORTER: "Well, sub, you all can go by any runs down about every day when I'm de- of paper and add your name and ad- clock you please, but you can't go by that livering milk." dress to each. train, fo' it's gone." SECOND MILKMAN : "That's because you Unavailable material cannot be -R. Hadly Waters, Rep. No. 27,808. have a short-circuit."-Wm. G. Mortimer. returned. CROSSED CROSSINGS-GETS CROSS SO IT IS RAY -RAY " H e speeded HE GOT ACROSS! TEACHER: "What is an X-ray ?" (ex -ray). up, thinking he LECTURER: We JOHNNY : "Oh, it's a kind of retired fish." could beat the lo- dug up a bed in -])avid R. Owen. comotive to it." Egypt twelve by "Did he get twenty-eight feet. across ?" WELL,YOUR HALITOSIS; KID: That's a "He will as lot of bunk. - 15 CURED! USELESS soon as the tomb- Leslie Carpenter. INFORMA- stone maker has TION finished it." Earle Bennett. Lockjaw is a - SO WOULD YOU BE surer cure for FAIR PASSENGER: "Why is the ocean so halitosis than lis- HARD BOILED terine I restless ?" - Henry JIM : "He thinks he's tough-calls him- CAPTAIN : "Well, one could hardly ex- A. Courtney. self a hardboiled egg." pect it to rest easy with so many rocks and JACK : "And, as you might expect, he's crabs in its bed."-Mrs. Annie L. Bates. yellow in the middle."-Joseph Wallace. SCIENTY SIMON, Scientist

yap : - - 1-14AT 15 JUST PLUG- R CENT FUSE SC(ENCf_ LESSO(J SHOT AND 'He Re -.- WTo THE POSE_ NO. (tI ?HERE GOES THE FUSE ISreT Ant EXTRA oNE (N 2E CEPrAc Le_ (5 At`1 pECTR(CAL - - ( MUST (4AUE THe f - - = An1D SHE'LL. FUSE Hoose DEEECE, BEIcJG SO CON- WORK 'A5 g5 GOT TH05E v4sReg SAFETY Ka:L."61.0erILL O . G-000 AS THAT if CROSSE STRUCTED of csi2 ANY EUE2 e, AN OOFRIOAD I"(IU ,SUCH AS A cOIA, METAL OBIECT CAP EQUALLY BRIDGE THE Wye 50/ CC EMERGEACY. WELL (A CASE P, AS MUCH OF (T cCdSTITUTES THE A5 fosrelInKrTBAM' HAZA2D OF A r FICEVALUE BDILE(A NEWS (TEM - A FIRE , BELIEVF_D TO FFAUE BEEÑ c.AUSFD gY DEFECTiUE- ,`12ESLAES (n) SEVERAL HODA; ED DOLLARS WORTH OF i,P.MAGE LAST (N GNT AT THE tI 0 e o Science and Invention for March, 1928 1023

VACUUM TUBE APPARATUS FOR ELEC- CAN VARIABLE CONDENSER TRICALLY PRODUCING No. 1,652,158, issued to Wilson Aull, Jr. This invention relates to a SOUND variable condenser of small volume No. 1,640,140, issued to Theodore per unit capacity, as compared to Bodde. This device consists of an other condensers in use today. The electron discharge device, which plates are separated by thin sheets transforms sound waves or im- of mica. The mica dielectric has a - pulses into corresponding current constant of four to eight times pulsations by the action of an elec- that of air. tron discharge tube.

II Illmll 11:7INIIïIIIIIï;P No 1,650,921 issued to Louis Win- !.ru: kelmann. The invention shown here is a vacuum tube whose elements are coated with a combination radio active substance and INVESTIGATING SUB- phosphorous, or a substance simi- TERRANEAN STRATA lar to phosphorous. No. 1,652,227, issued to Theodor Zuschlag. This method of inves- LOUD SPEAKER tigating subterranean strata consists in placing an antenna in a drill hole, causing high frequency PRODUCING oscillations in the antenna and as- üiïlllnn, NII:'7111r:i DISTORTED IMAGES certaining the resistance character- ISII11111117ME211111'r' istic of the antenna for each fre- No. 1,652,271, issued to Hereward Lester Cooke. The invention re- quency employed, and so deducing No. 1,651,552, Louis Rosen- the nature of the strata. issued to lates to methods and means of pro- berg. Two modifications of the can ducing dis- are shown above. A buffer for the torted im- bottom is provided which consists ages in a of a resilient element and a casing. pre - de- The shock of dropping the recep- termined tacle is thus minimized. Provision manner, is also made for longitudinal re- and also enforcements on the sides. provides for con- AUTOMOBILE BUMPER trolling the amount or direction of distor- tion so that the No. 1,638,245, issued to Charles image Crawford Davis. The radio repro- may be ducer shown above consists of two caused to diaphragms suspended from oppo- go through site ends of a support. All vibra- No. 1,647,627, issued to Samuel Horo- changes. tions are reproduced truly, as there witz. The bumper shown here has is no resonant frequency. The a number of independently oper- drive rod of the unit is connected able units. Each of these units to the ends of the diaphragms. comprises a pair of corrugated members and has springs interposed AERIAL SURVEYING BY between these members and the bumper units PHOTOGRAPHY-- TOOTHBRUSH STERILIZER AND FACIAL STEAMING CLOSURE FOR WATER No. 1,637,077, issued to Anna E. BAGS HOLDER Herrera. This device consists of No. 1,652,457, issued to Milton B. a veil to be folded about the body Beach. This invention consists of s-7 a liquid container having an elastic neck capable of being folded twice upon itself, and tension means permanently carried by the container for holding the folds under compression to make a liquid tight closure.

1 No. 1,650,978, issued to Johann Boy- kow. This method of surveying consists in mountaing a camera on two airplanes and taking photo- 4 No. 1,562,348, issued to John W. graphs of a common area to be Lockery. The individual tooth- surveyed, and a photo of the craft brush sterilizer and holder consists carrying the other camera. This of two side by side compartments, last named airplane is also pro- one which holds the antiseptic solu- and to cover the face. A breathing vided with a trailing rope of tion and the other the toothbrush. tube is also provided. All may be known length. Two variations are shown above. adjusted to various sizes.

NOTICE TO READERS: The above illustrated and described devices the Patent Office at Washington, D. C., give only the addresses of the have recently been issued patent protection, but are not as yet, to our inventors at the time of application for a patent. Many months have knowledge, available on the market. We regret to advise that it is im- elapsed since that time, and those records are necessarily inaccurate. possible to supply the names and addresses of inventors of the above de- Therefore, kindly do not request such information, as' it is practically vices to any of our readers. The only records available, and they are at impossible to obtain up-to-date addresses. -EDITOR. 1024 Science and Invention for Marcia, 1928

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The "Oracle" is for the sole benefit of all scientific students. Questions 3. Sketches, diagrams, etc., must be on separate sheets. Questions of all, but only matter of sufficient in- addressed to this department cannot be answered by mail free of charge. will be answered here for the benefit 50 cents is terest will be published. Rules under which questions will be answered: 4. If a quick answer is desired by mail, a nominal charge of submitted to be answered. made for each question. If the questions entail considerable research work 1. Only three questions can be rate will be charged. Correspondents will 2. Only one side of sheet to be written on; matter must be typewritten or intricate calculation, a special or else written in ink; no penciled matter considered. be informed as to the fee before such questions are answered.

diaphragm. HOT AND COLD WATER FREEZING tected, may remain at a higher temperature long spaces between the cap pieces and the enough for the exposed portion to freeze solid. The The air waves thus set up are then transmitted to (2237) T. Retsky, Hackensack, N. J., writes: ear by means of the rubber tubing my cold water will be kept from freezing by the the observer's Q. 1. For several winters I and several of circulation. and the earpieces. The small enclosed air space neighbors have experienced trouble with the hot in the bottom of the instrument between the plates while the water pipes which have become frozen VITAPHONE FADER and the diaphragm serves to dampen the vibration cold water did not. Can you tell me the cause of of the diaphragm. It is customary to use the geo- this strange occurrence? (2238) H. Quinn, Los Angeles, Calif., asks: phone in pairs connecting one instrument to each A. 1. This is an ordinary occurrence, but it Q. 1. Can you tell me how the changes are ear. In the first instruments, the diaphragms were seems that there should be no reason why it should made from one record to another in the Vitaphone, made of mica. It has been shown, however, that happen, as the hot water and cold water pipes so that it is imperceptible to the audience and also metal diaphragms are more sensitive and durable. usually parallel each other and are exposed to the how changes in intensity are produced. A nickel diaphragm of .025 inch in thickness, is same temperatures. The first experiment along this A. 1. '1'he Vitaphone provides for the reproduc- perhaps the best. The thickness of the diaphragm tion of speech or music as an accompaniment to enclosed record is apparently limited by the ability of the motion -pictures. A large talking machine bottom air pocket to prevent undue vibration. .-- WARM REGION A is made to accompany the picture. This record COLD -- PIPE. -*- LITTLE turns more slowly than the records on the ordinary PIPE -*- 40°F GCE ABOVE phonograph and is made large enough to play RADIAL MOTORS FREEZING throughout a standard motion -picture reel. The 4°C 15°C (2241) R. E. Foster, Russell, Ont., Canada, DENSE . TEMR needle running on the record drives a magneto - WATER phone pick-up device consisting of an armature asks: 32° F. moving in the field of an electromagnet whereby Q. 1. Will you please describe how the connect- ^ 0=C the vibrations which the needle receives from the ing rods are fixed about the crank shaft in a nine record' are produced electrically. A device known cylinder, air cooled, airplane motor? as the "Fader" plays an important part in this A. 1. On this page you will find an illustration new process. It consists of a series of adjustable which shows clearly the construction of the type of ti resistances, or attenuation networks through which motor mentioned above. Eight small connecting LIGHT rods are fastened to a large master connecting rod 60 °- the electrical currents from the magnetophone must A LITTLE WAT E R pass before entering the amplifiers. The object of which is made in one piece. 'rhe master connecting rod is shown in the topmost cylinder in the illustra- ABOVE 32° 32.°WATER the Fader is to afford a means whereby a change may he made from one record to another. It also tion. It is wider than the other connecting rods NO FREEZES but is of the same length. All nine connecting rods FREEZING serves as a control device whereby changes may be made from one record to another. It also serves as are held to the crank shaft by means of a master connecting rod bearing. A short stroke and large 'REGION OF a control device whereby changes in the intensity motor. This unusual FREEZING of the reproduced sound may be made as occasion bore are used in this type of 1.TEMR requires. arrangement is balanced by means of two counter weights which are placed as shown in the illustra- ,BELOW tion. This is the principle used in practically all ,32 F EXPLOSIVES present day radial motors. 0=C %/ (2239) P. Hamilton, Ft. Worth, Texas, asks: Q. 1. Will you please give me the composition MASTER CONNECTING DENSE SLIGHTLY of brown powder and of cordite? ROD. WATER ABOVE A. 1. Cocoa powder or brown powder is a FREEZING variety of gun powder made with a brown charcoal 32° F prepared from straw. It consists of the following materials: 0° C Potassium nitrate 79 parts Sulphur 3 parts LARGE SMALL' Strawcharcoal 18 parts Cordite is the principle smokeless powder of the CIRCULATION CIRCULATION British services. It was originally adapted in 1888 The above illustration shows the circulation and is made by mixing nitroglycerine with gun which takes place in a cold and warm water cotton and mineral jelly (a sort of crude vaseline), pipe. and incorporating them together with the aid of acetone, which gelatinizes the gun cotton. The --COUNTER formula for explosive mixture is as follows: line was conducted by Leon McCulloch research en- the WEIGHT 65 parts gineer of the Westinghouse Elec. & Mfg. Co. It Gun cotton SHAFT is a well known fact that water is densest or heavi- Nitroglycerine 30 parts CONNECTING/ J CRANK est a few degrees above freezing. On either side Mineral jelly 5 parts ROD BEARINGS MASTER CONNECTING of this temperature which is 39 degrees F. the During the World War a further variety was in- ROD BEARING. water is lighter. For example, at 44 Degrees F. troduced, which contains nitro -cotton of compara- 1 quart of water weighs 945 grams. At 39 degrees tively low nitration that can he gelatinized by means The illustration above shows the construction F. it weights 946 grams, while one quart of ice of ether and alcohol. This mixture contains the fol- of a radial motor having nine cylinders. weighs only 887 grams. Thus water changes in lowing ingredients: weight only about one part in one thousand when Nitro cotton 52 parts its temperature drops from 39 to 32 degrees F. WHITEWASH FORMULA is mobile however, Nitroglycerine 42 parts It such a fluid, that this small Mineral jelly 6 parts (2242) B. Brown, Vaux Hall, New Jersey, askes: decrease in density is enough to set up a circula- Will you publish in«the.Oracle a formula for tion by convection when the lighter 32 degree water is at the bottom of the vessel and the heavier 39 whitewash? THE GEOPHONE A. 1. We are giving below a formula which degree water is at the top. This denser 39 degree is used by the U. S. Government in making water starts to fall and the colder but lighter (2240) A. H. New, Meriden, Conn., asks: whitewash for light houses and other public water rises out of the way. Thus a circulation is Q. 1. Will you kindly give me some information buildings. set up as the point of freezing is approached. The concerning the instrument known as the geophoile Unslaked Lime 2 pecks diagram on this page shows, just how this is pqs- and something of its uses? Common Salt 1 peck sible and will greatly help in explaining the curious A. 1. The geophone is a sound ranging instru- Rice Flour 3 pounds phenomenon of the freezing hot water pipes. In` a ment invented by the French during the war. The Whiting % .pound pipe which is kept cold, the point where the tem- form of the instrument was developed by the U S. Glue 1 pound perature is 39 degrees will naturally be found Army engineers and the U. S. Bureau of Standards, Water, a sufficient quantity. higher up, that is, further from the point of freez- later the U. S. Bureau of Mines increased its Slake the lime in a vessel of about ten gal- ing, than will a similar point in the warm pipe. sensitivity. In principle the geophone is a seismo- lons capacity, cover it, strain, and add the salt The amount of water kept in circulation in the cold graph which is entirely, mechanical in its action. which has previously been dissolved in warm pipe will thus be greater than the amount that It consists of a flat iron ring about 3 i4 ° in dia- water. Boil the rice flour in water; soak the glue circulates in the warm pipe. This circulation tends meter and =4" in thickness, in the center of which in water and dissolve on a water bath, and add to keep the water at the bottom from freezing since is suspended a lead weight fastened with a single both, together with the whiting and five gallons the colder water rises and the warmer water falls. bolt through two metal diaphragms. One of these of hot water to the mixture, stirring all well The actual water pipes in a house are not closed diaphragms covers the bottom of the ring and the together. Cover to protect from dirt, and let at the lower end, of course, but the conditions may other, the top. There are also two brass cap it stand for a few days, when it will be ready be such that it amounts to the same thing. There pieces, the top one having an opening in its center for use. It is to be applied hot, and for that is often a horizontal stretch or pipe, along a cold to which is fastened a rubber tube leading to a reason should be used from a kettle placed over ceiling for example, just before the pipes pass a stethoscopic earpiece. If the instrument is placed a fire. freezing cold space through a floor into a slightly firmly on the ground, and if there is any pounding The whitewash may be colored by adding a warm room above. The horizontal pipe prevents or digging near it, the case of the instrument will small quantity of ocher, chrome yellow, Dutch convection and thus has the same effect practically vibrate with 'the earth. The lead weight, however, pink, raw sienna, for yellows and buff. Venetian as if the pipes were plugged at the bottom of the because of its mass will remain comparatively red, burnt sienna, Indian red, or purple brown vertical portions. When a hot and a cold pipe pass motionless, since it is suspended between the elastic for reds; celestial blue, ultramarine, indigo for up from a freezing region into a slightly warm diaphragms. Thus a relative motion between the blues. Red and blue are mixed for purple, gray room, the cold pipe may remain at about the 39 diaphragms and the case is produced. This motion or lavender; red lead and chrome' for orange; degree point, while the warm pipe, if slightly pro- alternately compresses and rarifies the air in the Brunswick green for greens. 1025 Scicncc and Invc,ntion for March, 1928

L .UD á C( k March

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NEW A..E-(Titrus/rated) NUN,N. MORALS, Graybar Bldg.. Nrw York Here's my dollar for a 6 -months trial subscription t, MOhLRN I S M shirt wit 4i tlu 1l:vch issue. ./in hi1ciwrcuT cvrtlt Nanas ho11-th hl1kIfltfltl Address Ciltt .átate Science and Invention for March, 1928

Where Many WHAT MAKES AN AUTOMOTIVE MECHANIC? By HENRY TOWNSEND AUTOMOTIVE (Continued from page 991) garage apprentice has the ambition to study trouble is with the carburetor at all. some of the theory books on engines, elec- What we wish to point out to aspiring EXPERTS trical ignition and lighting systems of cars, automotive experts and mechanics is not he will learn practically nothing of the theory primarily the fact that one can, in a modern in his three to four years' apprenticeship. automotive trade school, become a mechanic Get Their Start Compare this for the moment with the capable of earning a salary of $40 to $50, graduate of a modern auto trade school a week in a period of three to six months; THE man of today, in any branch of busi- where competent instructors first teach the whereas a garage apprentice will have to ness or profession-with a thorough tech- students, and then give them daily and serve at least three years' time in order to nical training, has a wonderful advantage weekly quizzes in order to ascertain whether command the same wages; but the much over his less fortunate brothers. the student has actually mastered the tech- more important fact that the graduate of And today, most all employers of automotive nical details, whether it be theory or prac- a first-class trade school has a very fine help are seeking graduates from Automotive tice. Naturally the longer a man practises training in both theory and practice. The Trade Schools of Character and unquestioned the more rapid and efficient he becomes, and mechanic taught by the school knows just reputations. They want men who "know"- as a director of one of the leading auto- what is going on in any part of the motor not "guessers." motive trade schools pointed out to the car machinery, whether it be engine, car- A certificate from a Training School of this character writer, some of the students remain in the buretor, ignition, lighting, is a real asset to any man. He has no difficulty in or differential getting a start. Thousands of men now successful in school for one to two months longer, in gear. the automobile business owe their prosperity to order to obtain more actual practice in the Just to give an example from everyday acquiring a thorough, practical, and scientific knowledge service department of this institution. life, it cost the of auto-mechanics. author of this article nearly There are plenty of half -trained men who find work Of course many people will raise the ob- the original price of a car in one year, during the rush, but the skilled man finds his services jection against a trade school that the stu- simply to keep it in repair. What do you in demand winter and summer, anywhere. dent is quite likely to receive too much think the true answer to this state of affairs theory and not enough practice-for it is is? He can tell you truthfully that there well to remember that a man does not learn is only one answer, and although this case to use wrenches, electric drills and other occurred several years ago, there is no shop tools simply from reading a few nicely change in the writer's mind as to the blame bound textbooks. Thus it was a very agree- for such a garage bill in a twelve month able surprise to the author upon visiting one period-the answer is incompetence. of the leading New York automotive trade A further extension of the analysis shows schools, that he found dozens of students beyond a shadow of a doubt that if properly busily engaged in actually assembling and trained automotive mechanics had done the disassembling well-known makes of cars, all work on the car in question, the monthly under the direction of their instructors. garage repair bills would have been not Let us consider for a moment a very in- more than twenty-five per cent of the amount teresting comparison between the subjects that they finally totaled. When the garage mastered by the average apprentice in a mechanic has to replace an engine fly wheel garage and a properly taught auto school three times in three months, due to the student. How many of the garage mechan- teeth being knocked out of the fly wheel, ics you meet in your travels can answer because the starter -motor pinion had the "yes" as to their ability to properly per- wrong number of teeth on it, there is some- form the following work :-Diagnose vari- thing radically wrong in the training of the ous ills of the ignition system and make the mechanic who handled this job. necessary repairs ; weld a motor car frame Today, as never before, industry every. or properly straighten an axle ; explain how where and particularly the automotive field, any one of twenty different makes of car- demands men who know both practice and buretors perform, and be able to diagnose theory, especially when it comes to the serv- quickly just what is wrong with the car- icing of 22,000,000 motor vehicles now owned huretor on a customer's car; if, in fact, the and operated by the American public.

MOTOR HINTS Conducted by GEORGE A. LITERS (Continued from page 1004)

More difficult QUICK MOVEMENT, OF TESTER HANDLE, than usual, is the job of MAKES PLAY AT THESE PLACES EASY holding a connecting rod cap or a steering TO OBSERVE AND HEAR. gear or radius rod ball socket cap. If two Completed May, 1927 PIPE. EL Bo bolts with double nuts, are arranged on the PIPE jjfl w bench as shown, these caps can be held so The above illustration is a fair reproduction of the NIPPLE as not move new home of the Stewart Automotive Trade School "Mae to while filing faces for adjust- -founded 19 years ago. It is located in the heart of ment. the Automobile District of New York City. It was specially designed for this purpose. It's fire proof- SLOW MOVEMENT, TESTER FOR PISTON AND VALVE splendidly lighted-well ventilated-and specially OF TESTER arranged for the convenience of its students. SHOWS TROUBLES The shop equipment is complete with all modern DEFECTS AT appliances and facilities. The instructors are the THESE LOCATIONS, The tester is made from a single cylinder best obtainable. THROUGH tire pump, in which an extra leather plunger If you have a liking for mechanics and wish to enter PASSAGE OF AIR. is inserted on the pump rod, the automobile field and be properly trained-in a in a reversed city where the demand for skilled men is greater position. and salaries larger than anywhere else-return the PISTON The bottom attached coupon and we will mail you our new catalog of the pump is cut off and and information in detail of our system of training- WRIST PIN fitted with a X inch pipe nipple. A X inch tuition fees, and cost of living in New York while elbow is used to connect this to a special being trained, etc. DOUBLE PLUNGER ON PUMP ROD. nipple made with one end to fit the spark plug hole. Stewart Automotive Trade School The nipple and elbow are screwed into 257-C West 64th SL, New York City the engine and the pump is then screwed to You may send me your FREE Catalog, illustrating your these. shops, and complete description of your training methods, terms, etc., without any obligation on my By quickly moving the pump plunger in part, whatever. and out, lost motion in wrist pin or con- CONNECTING necting rod bearing can be detected. A Name Age ROD BEARING. steady pressure on the pump plunger will indicate by air leakage, if rings, piston or Address valves are broken loose or leaking. It is advisable in making tests to have the en- City State Use of the tester for indicating piston and valve faults is shown above. gine crankcase removed. Science and Invention for Marcia, 1928 1027 WHOLESALE PRICE S forglealers,Communiíy Set$uilders,General Repairmen r and iqents! Be sure to get this great 128-page book with net prices to the radio trade. Radio Specialty Company is radio's oldest radio parts mail order house in the country, and the new confidential prices on standard radio merchandise are the lowest of any radio house. We are ready now to appoint additional agents in all parts of the country. If you are contemplating making big money in radio merchandise, be sure to get in touch with us at once. WHEN WRITING TO US, USE YOUR LETTERHEAD

ENLARGED EDITION fy THIS NO.18 91&75 128 PAGE 41OOKUPs RADIO 500 CATALOGU E I LLU STRATIONS ItEg jjtt131111from Radios Oldest ?hail Orderilouse! instruments We are the oldest established, exclusive radio mail order house in the country. teous service. We carry a larger variety of radio parts, radio in the country, All orders are positively shipped within twenty-four hours; quick, prompt, cour- accessories and radio findings than any other radio house You will find in Catalog No. 18 the largest assortment of radio merchandise in this country. Radio Specialty carries more radio parts and radio material than any other house in the country. You will find in this catalog positively the largest variety of radio merchandise. dRASCO''has If you are in need of certain small radio parts that other radio and mail order houses do not bother to carry, get the Rasco Catalog and you will find the small parts there, anything from a screw to copper ribbon, telephone dvaphragms, as well as thousands of other small radio findings. Just to mention a few: Lugs, nuts, jacks, plugs, all kinds of knobs,cords, panels, screws, sliders, washers, selenium, tinfoil, switches. crystals. cap nuts, Litz wire, cord tips, brass rods, resistances, binding posts, switch parts, carbon balls, switch points, lock washers, carbon grains, ground clamps, metal pointers. ANYTHING insulated tubing, low melting metal, antenna connectors, as well as thousands of other articles. We carry the Largest Variety of Small Radio Parts in. IN RADIO the World, BUT We also carry All Standard Radio Merchandise.

loo PARKPLACE NEW YORK 1028 Science and Invention for March, 1928

ELIMINATING FATAL "TAIL SPIN" By C. A. OLDROYD (Continued from page 990)

Two photos at right show Handley Page wing slot open and closed. This simple device will eliminate 85 per cent of tail- spins, it is claimed.

has experimented with airplanes fitted with Now Cormes the slotted wings. An experimental machine is illustrated in Figs. 5 and 6. Here is the New Shorthand auxiliary plane, which, For years there has been a crying need for provided with the slot, a new system of shorthand-for a really was actuated by the modern, scientific system, that could be pilot through a control written more RAPIDLY than the conven- gear. tional sign systems, that would be more The experience ACCURATE-and that could be learned gained in these tests EASILY and QUICKLY. led to the latest truly Now at last it is here-the new shorthand. revolutionary develop- The business world has hailed it with en- ment, the automatic thusiasm. Already it is saving time and stabilizer. increasing efficiency in offices everywhere. Fig. 7 shows an air- Busy executives are using it themselves. So plane fitted with this are professional men and women. Ex- device ; narrow auxil- perienced stenographers as well as beginners iary planes are hinged are adopting it. It is used in the U. S. to the leading edge of the wing. But these visible giant grasp the wing tips of the air - Army and the Navy. auxiliary planes do not reach from one end plane, thus making an incipient spin im - + of the wing to the other; a short plane is possible. fitted at each side, near the wing tip. The Handley Page stabilizer is the re- ºiMWi,e sult of many years' strenuous experimental ne `AIATURAL SHORTHAND HOW WING SLOT WORKS work, and aeronautical experts agree that advance in heavier-than-air the The action of these auxiliary planes is it is the greatest You use only the ordinary letters of illustrated in the diagram (Figs. 8-10). In machine design the world has seen for many same A B C's you have always alphabet-the Fig. 8, the wing is shown inclined at a years. used. Speedwriting is simply a scientific All new machines of the British Air Force of the English language, based POINT OF condensation will be fitted with the new stabilizer ; and at on your natural habits of speech. MAXIMUM PRESSURE the time of writing, experiments are pro- QUICKLY LEARNED AT HOME ceeding in London, England, to determine the best way of using the stabilizer on the Eng- need to memorize a "foreign language" AIR PRESSURE X No BEYOND THE lish airliners plying between London and dashes, hooks and curves. You INCREASES AS THE CRITICAL ANGLE of dots and and German airports. can start using Speedwriting almost at .once. ANGLE OF INCLIN- THE AIR PRESSURE French, Dutch Amazing speed is quickly developed. ATION 15 INCREASED DROPS SUDDENLY Speedwriting was originated by Miss PRE URE Emma Dearborn, famous authority on short- CU VE THE FUTURE OF TRANS- hand. She has taught practically all systems for eighteen years in such institutions as ATLANTIC FLIGHT Columoia University, Rochester Business WILLIAM SULLIVAN Institute, Simmons College, and the Uni- Aeronautical Engineer and Specialist versity of California. in Design of Modern Airplanes and Dirigibles ANGLE OF INCLINATION OF LV/NG SEND FOR FREE BOOK yoy- will discuss a new way to Let us tell you more Fig. 2. This chart shows the relation of the about Speedwriting-how various forces acting on an airplane in flight. solve the problem of trans- Sffleedtvrvting experienced stenographers and beginners alike are oceanic flying in the APRIL adopting it-how presi- normal flying angle, the flow of air past dents of firms, sales man- number. agers, and other impor- the wing section is even and orderly, and tant executives are in- in this condition, the auxiliary planes lie creasing their efficiency up leading through its use-how all against the edge of the wing, kinds of professional men, blending into its outline. college students, and office In Fig. 9, we have the same machine on workers are finding it in- PROPELLER valuable. Send for the the point of stalling. The air flow has be- PULL Free Booklet now-it shows what Speedwriting come disturbed. As soon as this condition can do for_YOU! appears, the small auxiliary planes come into SYSTEMS, INC. action. BRIEF ENGLISH ANGLE OF Dept. C-94 TAIL SPIN STOPPED INCLINATION 200 Madison Avenue New York City WING SECTION 'OF WING Automatically, they swing out on their CENTER OF -__.MAIL COUPON FOR FREE BOOK NOW!___ hinges and assume the position shown in PRESSURE Brief English System, Inc., Dept. C-94 Fig. 10, thus providing a narrow slot be- 200 Madison Avenue, New York City tween the main wing and the auxiliary planes. Air this slot, estab- Gentlemen: Without obligation, send me your booklet rushes through P on Speedwriting. lishing once more an even flow of air in the TOTAL It I decide to study Speedwriting. I shall use it In VERTICAL region of the wing ends. LIFTING AIR PRESSURE Stenographic... Executive... Secretarial... Student... ON WING or Professional... capacity. This action of the auxiliary planes holds EFFECT the airplane on an even keel, even when Name stalled, the nose of the machine dips slightly, AG we see the interrelation Address Fig. 1. In this figure and flying speed is automatically regained. of forces from propeller pull, wing pressure, drag. City Stale One might say that the hands of an in- vertical lifting effect, and the Science and Invention for March, 1928 1029

New Apparatus for Retinal Examination (Continued from page 995) return through the pupil, again to the convex mirror, which gives a reversed clear image of the retina. This image is studied by the observer through the eye -piece as said image falls upon the plane mirror. The retina is seen four and one-half times magnified. If greater magnification is desired, additional lenses can be screwed into the eye -piece giving seven to ten times the magnification. At one end of the apparatus there is an eye screen to cover the eye of the patient, and at the other an adjustable eye -piece for the observer.-Contributed by Dr. Albert Neuberger.

Strange Hobbies and Crafts of Successful Men BY GEORGE H. DACY I Turned To Ice When (Continued from page 993) To Talk and orna ITried t le A, B, C's of furniture making mental whittling. He brought home un - -But Now I Can Sway An merchantable and broken pieces of hardwood lumber from his yard and converted them Audience of Thousands! into handsome book shelves, chairs, tables, articles. book -ends and other household I HAD always been painfully bash- Soon I had won salary increases, promotion, popu- CHIP CARVING AN INTERESTING PURSUIT ful. When trying to carry on even larity, power. Today I always have a ready flow The art of Norwegian spot cutting or of speech at my command. I am able to rise to chip carving has come to America from the most commonplace conversation any occasion, to meet any emergency with just the Northern Scandinavian countries. Cen- my voice would sound unnatural and the right words, to approach all types of people turies ago, the art came into being among my hands and knees - with ease and fearlessness. And I this by develop- the peasants of Norway and Sweden who would tremble. Often I accomplished all spent the long winter evenings beside their What 20 Minutes a Day ing the natural power of speech listen to an argu- Show You hearths carving tough wood with razor- would Will possessed by everyone, but culti- edged tools. One of Stockholm's finest ment among a group and Flow to address business meet- vated by so few-by simply ings spending 20 minutes a day in my exhibits of to -day is a collection of this become so keenly inter- How to propose and respond to own home on this most fascinat- wood carving of the seventeenth century. ested that I would want toasts Oak and walnut are the best woods now How to make a political speech ing subject. although to voice my own opinion How to tell entertaining stories available for chip carving activities, How to write better letters Send for This yellow pine, birch, mahogany, hickory and -yet timidity would keep How to enlarge your vocabulary wood carver first How to develop self-confidence Amazing Book ash are also used. The me silent. I never had the How to acquire a winning per- makes his book rack, tabouret, foot rest, courage to stand up for sonality This new method of training is Then How to strengthen your will- veryinterest- panel, picture frame or-what not. I knew to be my fully described in a he draws an appropriate geometrical design what power ing and informative booklet I was always How to be the master of any on the article and finally carves or chips out rights - situation which is now being sent to every- this ornamental pattern. Fancy initials and afraid of "what people one mailing the coupon below. ornamental scrollery, such as one commonly will say," ridicule )Since This book is called, How To metals, may Words. to it you are shown sees worked into brass or other my childhood I had had a secret de- Work Wonders With be as satisfactorily carved in hardwood. how to conquer stage fright, self-consciousness, Hand -carved costumers, wall seats, con- sire to appear in public-to be active timidity, bashfulness, and fear-those things soles, night stands, serving tables, pedestals, in politics-but my shyness was so that keep you silent while men of lesser ability bud vases and candlesticks are commonplace great that I turned to ice when I tried get what they want by the sheer power of in the Scheve home. They represent the to even the smallest gathering! convincing speech. Not only men who have efficiently utilized leisure of a successful talk-in made millions, but thousands have sent for this lumberman. His attractive house is over- My inability to talk was also affecting my book-and are unstinting in their praise of it. flowing with the products of his handicraft. business success. I dreaded going in and asking You are told how to bring out and develop It would cost more than $2500 to purchase for a raise-I was afraid of any situation that your priceless "hidden knack"-the natural gift hand -carved articles like those that adorn meant using my voice-having to express my- within you-which will win for you advance- this home. The experience of Mr. Scheve self. I didn't know how to present the ideas ment in position and salary, popularity, social which I was sure the firm could use. I was just success. You can is that a man can enjoy a hobby, reap di- standing, power and real _. of doing a lot version from its practice and still make the a plodder-a truck horse, capable obtain your copy absolutely /------"'""_ of heavy work but of no use where brilliant per- free by sending the coupon pastime a profitable form of recreation. men Glenn Warner in charge of athletics at formance was required. Often I would see is who were not half so thorough nor so hard work- Leland Stanford University, California, they made one of America's famous football coaches. ing as I, promoted to positions where Now Sent a brilliant showing-not through hard work, but / For many years, he trained the former Car- elevens and later was through their ability to talk cleverly and con- lisle Indian School appearance of being FREE I head coach at Cornell University and sub- vincingly-to give the efficient and skillful. sequently served the University of Pitts- NORTH AMERICAN INSTITUTE burgh in similar capacity. a Day 1423 When Mr. Warner is not busy with ath- In Twenty Minutes 3601 Michigan Avenue Dept. letics, you will find him in his workshop de- And then suddenly I discovered a new easy Chicago, Illinois signing and making golf clubs or else out method which made me a forceful speaker almost North American Institute, on the links testing the products of his overnight. I learned how to dominate one man 3601 Michigan Ave., Dept. 1423 Chicago, Illinois. amateur handicraft. This man Warner has or an audience of thousands-how to say just the Please send me FREE, and without obligation, styles of just the right time, how to win my copy of your inspiring booklet, How To Work originated many new types and right words at Wonders ;VIM Words, and full Information regarding clubs. He has tested out many varieties of and hold the attention of those around me, how to your Course ln Effective Speaking. yet in a wood. Some of his finest club heads are express my thoughts simply and clearly, Name made from a bed of beech wood in which pleasing, interesting and amusing way. In just a the gridiron mentor slept for many years. few months I was able to make campaign Address He has also found that fish pole bamboo speeches for a local candidate-I who a short City Slate. can be used satisfactorily as shafts in both time before had turned to ice when I tried to wooden and iron -headed clubs. carry on an ordinary conversation! L 1030 Science and Invention for March, 1928 STRENGTH Hints for the Mechanic i and MUSCLES TOOL HOLDER FIRST PRIZE-$10.00 A special tool holder is shown in the above sketch. The body of the holder is made with FREE the usual tapered shank. It has an adjust - Never before has such an offer been made inithe muscle building field. Here is the opportunity to develop those skinny muscles of yours and become a fellow of physical power. This free cable exerciser will put a pair of arms on you that you will be proud of and your friends RECESS envious of. Your shoulders, back and chest will be FOR TOOL HOLE TO greatly improved in development and shape. SUIT DOWEL

Details of the tool holder are shown above. able nut which forces a heavy spring into contact with a loose sleeve. The sleeve is of a pin prevented from turning by means The details of the dowel jig are given in the in the body of the holder.-C..4. Liters. above drawing. DOWEL JIG HOLDING SMALL SCREWS The dowel jig shown here is made from a piece of square cold rolled steel, about two and one-half inches long. This is piece A. The back, C, is another piece of steel about A Strong5-Cable Exerciser, like this. with Course four or five inches long, which is attached to block A. The illustration shows how the YOU GET A STRONG 5 -CABLE EXERCISER jig is used. It can be made in various sizes. -Witt. A. Kyle. FREE and An illustrated course of instructions on how to use this MARKS ON WOOD apparatus for the purpose of deriving the best results FOR CENTER from it. This free exerciser is strongly made with black japanned grips and ends. The cables are made of a fine OF DOWEL grade rubber and covering. It's the ace of offers- see coupon below. HUNDRECS ARE BEATING YOU TO IT EVERY WEEK CLAMP We are prepared to take care of a large number of orders, but advise you to get your order in as early as possible FOR A practical method for holding small screws if you want prompt service. HOLDING is shown above. The hundreds of men, boys, and women who are taking advantage of this unusual offer prove the greatness JIG IN Small screws may be held securely, so that of it. It is without a shadow of doubt the peer of all POSITION they may be put in place, by sticking the offers pertaining to health, strength, and muscle developing methods. screw between the teeth of a small comb. The use of the dowel jig is shown above. The In this way it can always be held in a satis- device is and is accurate. factory position. WHAT AN OPPORTUNITY ! very handy quite Frank W. Bentley, Jr. WE PAY ALL MAILING CHARGES "Strength" MINIATURE CITIES-HOW BUILT isamagazineof enjoyableread- By LEE BLACK ing matter on (Continued front page 997) all subjects of health, strength and physical development. PAPIER-MACHE MOUNTAINS There are sports from a few hundred dollars to many thou- stories: articles sands for a single composition. If properly The mountains in the background were on how to develop the var- made and simple precautions are observed modeled ill papier-mache and plaster com- ious muscles of to position, your body. Stor- protect the subjects against the elements, the elevations and physical forms ies and articles they can be preserved for hundreds of years. being determined by means of reference to about the do. ings of inter- contour maps of the section. A waterfall national strong HOW A "MODEL" SOLD FIG ORCHARDS (which is not visible ill the photo) leads men and men with perfect In the accomanying illustration a well naturally, through mountain rivers to the physiques. dam which is There are pic- known western latid development company visible with the lake just tures galore of back of it. Since no blue -prints of the dam finely builtmen shows how it resorted to the use of a and women and miniature to solve a perplexing problem of were available it had to be fabricated by many other calculation and recourse to many photo- items of inter transportation and sales. This concern had est to the man developed a vast amount of acreage into fig graphs taken from various angles at the or woman in- actual site. terestedin phy- orchards. The land was several hundred sical fitness. miles from the home office and the time and The large white building in the middle dis- expense required to transport prospective tance is the hotel on the main street of the GET THIS COUPON OFF NOW! purchasers of land presented an enigma. town adjoining the property owned by the developers. The original is of stucco and r A decision was made to have a full the miniature is of wood construction, over THE MILO PUBLISHING CO. S.I. 3 2.3 modeled, por- 2747 N. Palethorp St., Philadelphia, Pa. section of the land faithfully which a plastic paint of a true stucco tex- Gentlemen: Enclosed you will find 52.50 for which please traying the stage of development, the enter My name for a year's subscription+to your ture is applied with a brush and a small "Strength Magazine." and send me free of extra charge facilities and general environment, such as flat tool, which produces the same effect whatsoever, the complete 5 STRAND EXERCISER COURSE. proximity to railroad, source of water and as the trowel in actual practice. and electric power, method of irrigation, acces- Name The original of the railroad station at sibility of nearest town, etc. the left was stuccoed by the pressure -hose Street The writer selects this as one of many methods so that in the construction of the City State he has built because of the wide diversity in miniature it was necessary to apply the the subject -matter and because of the diffi- plastic paint, mixture with a small air -brush. CANADIAN ORDERS, 52.75-FOREIGN. 53.00 culty of obtaining proper data. 'Continued on- page 10361 Science and Invention for March, 1928 1031

Flying Blind By G. E. SPENCER (Continued front page 982) volved. The pilots were shown on the ground, in a few simple experiments, how their flying sense could lead them to death. Know your Radio Repair Your Radio ti Yourself The Radio Trouble Finder Makes It Easy! NO matter now much or how little you know of your radio re- Trouble The improved plot test chair, fitted with ceiver, this new "Radio eye -shield and apparatus for determining Finder" book is going to be a big help. pilot's ability to fly by instruments only. It explains the common and special The instruction was so vivid that every man faults of all the standard receivers of not only eagerly agreed to use the Ocker - today; tells how to recognize in- Myers system, but in a few days none would stantly, by various methods, where fly without it. the trouble lies, and also gives special FIRST SUCCESSFUL FOG LANDING simple tests by which you can deter- Air Mail Pilot J. L. Rutledge was the mine is wrong with your re- first pilot to land entirely by instrument fly- what ing. He recently brought down a fully ceiver. Then for each particular fault laden air -mail plane in a fog, which offered there is explained the proper pro- no ceiling. That is, the mist extended down cedure for correcting it. to the ground, allowing no visibility whatever. The fog landing was affected entirely THE COPY through the use of instruments, which in- 25c. formed the pilot of his altitude, rate of de- ON ALL NEWSSTANDS scent, banks and turns, and what is most im- Gi:lble Still trying portant, prevented his being overcome by o locate trouble, vertigo. Of course the pilot knew the loca- 64 PAGES of Tests, Diagrams tion of his field. Had he been over mountains or heavily wooded terrain, he would and Simplified Trouble Charts have faced the same possibility of death or serious injury which would attend any at- Size 6 x 9 Inches tempt at bringing his plane down in such a location. To obviate this kind of landing Handsome 2 -Color Cover only the better organizations of airways can suffice, but already the Ocker -Myers system Published and Distributed by guarantees the safety of blind flight in the CO., INC. vicinity of all regular landing fields, in col- The CONSRAD laboration with necessary activities on the C 230 Fifth Ave., NewYork, N.Y. part of the ground personnel. (Continued on page 1037) P.M.* Gives up ira ds5 uSt 1111

he bought

THE CONSRAD CO., INC. 230 Fifth Ave., New York Gentlemen: I enclose 25c. for one copy of THE RADIO TROUBLE FINDER. Name Address City State Close-up view of new pilot test apparatus for "flying blind." Science and Invention for March, 1928

VISITING OTHER PLANETS By JAMES NEVIN MILLER (Continued from page 998)

,11,111,11111,1111,,,,11,,,,,,,,,,,1,,,,1,,,,,,,,,,,,,1,,,111,,. The illustration here shows the earth and its phases as seen from the southern polar regions of the moon. Top - full earth ; bottom - last quarter.

TERRIFIC HEAT ON MERCURY Journeying next to the planet, Mercury, closest to the Sun of the starry bodies, the He Gets astronomer who set foot on this planet, doubtless would mo- mentarily forget his What He Wants scientific observations in the face of a ter- HE'S the most popular fellow rible heat. Indeed, it in town; a shiek in the parlor, a is doubtful if he could under it, for he could not possibly Some astronomers believe here - survive the atmosphere ring leader with the boys. W avoid it without travelling to the opposite is exceedingly rich in water vapor, and ever he goes he gets what he hemisphere. others that it contains none at all. wants his What manner of landscape is lighted by "At any rate, the density of its atmosp.`iere with this colossal furnace? Unfortunately, but is very great, almost double that of curs. little is known of the mysterious planet in Upon the surface of Venus, covered with this respect, though it is probable that its this dense atmosphere, diffusing the intense surface is covered with high mountains. As light from the enormous sun as seen from for its atmosphere, that, too, has not been there, a sort of luminous and troubled fog True crone Saxophone detected by the astronomers. must singularly limit the range of vision, Do you long for social popularity? The admiration of friends? A welcome hand at gay parties? Good times with those you like best? Do you want At the left is shown a to be successful?A favoritewith your view of a typical small "boss" and your fellowworkers?All lunar crater. Note the peculiar formation of the these things, and more, are yours if substance forming its you will learn to play this most won- outer edge. derful of all musical instruments. YOU Can 'Do It, Easy Within a week you can be playing tunes. 3 lessons, given on request with each new instrument, explain easy fingering and VENUS COMES TO VIEW doubtless preventing the enjoyment of any give you quick start. You might even be a Seen from Mercury, the planet, Venus, extended landscape. What are these land- wizard like Tom Brown, whose Buescher which is farther off from the sun, would, scapes ? In lieu of anything better, let us Saxophone has made him famous and rich. at certain times, appear to he a truly blind- suppose there exists here a surface, with ing star. Here again, science knows but some land but much water. Through the YOU Can 'Do These Things little. The body appears to have a brilliant dense atmosphere, the stars are either But how can you be really sure that you whiteness, but none of its details may be slightly or not at all visible. If the sun can learn to play? Well! Can you beat time detected because its thick, cloudy atmos- can be observed at setting, the phenomena to music? Can you hum a tune? Could phere hides its surface from the eyes of of refraction will be noted as on earth. but you thump out"Home, Sweet Home" with man, however aided by scientific instruments. will be very much more in evidence, modify- one finger, at the piano? Only 'Buescher e..4ssures Success ,e111111111111111111111111111111111111111111111111111111111111111r Then you can learn to play a Buescher. But only with the simplified fingering of the Buescher Saxophone is rapid progress assured. You don't have to favor and fuss for certain notes.You just Here we see the earth open or close the key and blow normally. It is and its phases as viewed almost as easy as the "one finger solo" at the piano, but oh! how beautiful. from the southern polar Try a Buescher, any instrument you choose, in your regions of the moon. Al- own home for six days.This is a most liberal offer. though the earth appears If you like it, pay a little each month. Play as you pay. Without obligation, mail coupon below at rest in the sky, the for beautiful literature and details of the free sun moves along horizon- trial plan. GET STARTED! NOW. tally beneath the horizon, hid by the moun- BUESCHER BAND INSTRUMENT CO. everything in and Band Orchestra Instruments tains, whose summits are 2308 Buescher Block Elkhart, Indiana illuminated by it. Top- .-. earth surrounded by its brilliant atmospheric BUESCHER BAND INSTRUMENT CO. 4 2308 Buescher Block, Elkhart, Ind. ring. Bottom - last I Gentlemen:Without obligating mein any way please send me your free literature. Mention instrument interested in. quarter. Age/ Name instrument Name

111111111111111111.11111111,t1t111111111111.1111111.11111 1111 Science and Invention for March, 1928 1033 ing strangely the appearance of the solar disk." WE LAND ON MARS Arriving next at Mars, farther away from I;eIARy the sun than the earth, the traveller should I.IAPgRY LBW' ' UMW I1BR0 CtBRRF feel much more at home, for atmospheric l y Nee, IbLl:[ü ix,iark. %toILU [l'ctlCdt ,QmA! ÉlRlalT 57C7`_In- conditions are quite familiar. Even day and EtECiF!LT' lde Ewe RSt. night are scarcely longer than on earth. Through an atmosphere somewhat less dense the stars will appear in splendor, enriched ® ® 0 ® by two small moons. The smaller of these ElectricitgKnow ,_.--. t1iRING fand not only will seem to move with great speed =.,ritçat %LIM hXtwu. E++IniClj ceinte w(WJtG EICIAMT %mug =TAn, t JI tt but in an opposite direction from the appar- mkt, Av Powta uam: wk. eNOrf ..*tin CR °=-tR óFT ' ent movement of the stars ; indeed, it re- volves about Mars faster than the latter ro- as Exp erts tates upon its axis. "At certain epochs, either in the morning or evening, the earth will be visible as the morning or evening star, respectively bril- Know It liant in the dawn or evening dusk, the latter of short duration because of her `vçRbY NeGRAN !ICCRLW Mr N'ZIt- the rarity of oolo =moo the Martian atmosphere. The sky will ap- . pear darker during the daytime and the sun, a third smaller than from the earth, THIS is the electrical age, with unlimited opportunities for the man who has edu- will illumine less brilliantly the doubtless cated himself in the finer points of electrical practice. more monotonous landscape. The most reliable observations indicate a ground with Fit yourself for one of the really big jobs by knowing electrical practice complete, very little relief, probably almost every- including inside and outside work, central stations, and the whole subject. With the where level, cut here and there with enor- aid of the Croft books you can know electricity as experts know it and put yourself mous swamps." in line for an expert's pay.

JUPITER, SATURN, URANUS AND Flexible NEPTUNE binding How about conditions on the giant planets, for easy The prof t Library handling Jupiter, Saturn, Uranus and Neptune? Un- fortunately, a human traveller would no longer find himself upon solid ground in of Practical Electricity the strict sense of the word. For it is prob- A reference library and self -training course in able that these worlds are still fluid, or at eight volumes. 3000 pages -2100 illustrations any rate, semi -fluid, making a landing place The Croft Library contains three thousand pages, with twenty-one hundred of the clearest illus- virtually impossible. However, supposing trations ever put into book form. Each of the eight volumes is indexed so that everything you want that the traveller could alight on Jupiter, to know about electricity is at the fingers' ends. And when you find what you want, there is not merely for instance, would he be able to see the a short question and a short answer. You are told everything you want to know. The explanation is heavens through the thick and dense atmos- clear to you, regardless of whether you have had a previous knowledge of electricity or not. Croft teaches you electrical practice complete. He takes you in quick, easy steps from the simplest phere whose storminess we can observe from principles to the complete and economical operation of a great central station. our earth? Imagining such to be the case, He tells you the things you need to know about motors, generators, armatures, commutators, he could see the sun as a tiny disk, shining transformers, circuits, current, switchboards, distribution systems-electrical machinery-wiring for with light twenty-five times fainter than light and power-wiring of finished buildings-underwriters' and municipal requirements-how to do a complete job, from estimating it, to completion-illumination in its every phase-the latest and most that seen from the earth. That would be improved methods of lighting-lamps and lighting effects, etc. very meager for a sky so heavily clouded. Jupiter's globe turns upon its axis once in 9 hours and fifty-five minutes. The suc- THE STANDARD IN PRACTICAL cession of day and night therefore is very rapid; only 5 hours elapse between the rising ELECTRICAL TRAINING and the setting of the diminutive appearing Everywhere the Croft Library is acknowledged as the standard-the leader-in practical sun which passes rapidly across its sky. electrical training. It is the daily guide of 59,000 highly -paid electrical workers and engineers. There is nothing like it in print today. It is the most complete, the best illustrated, the most "Jupiter has 9 moons but only 5 are visu- carefully compiled, the most easily understood electrical library available. No matter how ally of any importance nor can all be seen much or how little you know of electricity, you will find the Croft Library a sound, helpful at the same time. Their apparent size, reck- guide to greater accomplishment. oned from their actual size and distance Every day you use these great books you will learn something that will help to make you a better electrical worker. Every page is taken from every -day electrical practice. Croft from Jupiter, shows them to be comparable deals only with the kind of problems you meet in daily work. Own a set and join the 59,000 to our moon. They are of greatly dimin- men who have found the Croft Library to be a real working companion to bigger accomplishment in the electrical field. Keep these books handy in your room. Put one in your pocket when you take ished brightness since the sun illumines them the car or train in the morning. Give them the odd hours. They are not tiresome treatises, but as interesting much less intensely." s any reading matter you ever owned. Consult your set regularly, acquire just one new fact a day, and in The moons of Jupiter offer perhaps more few years you will be_a broadly informed electrical man. solid footing. From the nearest one Jupiter itself would look like an immense moon, 10,000 times larger than the moon looks to Easy Steps to Success in Electricity man from the earth. Starting right in with the ABC's of modern what is needed to get ahead. He has poured out all electricity, Croft takes you through his books in his knowledge-all his experience-in language that SATURN easy steps. He gives you the boiled -down records anyone can grasp. Yet the text is so scientifically of every -day electrical practice in plain words, correct that thousands of the highest -paid electrical "Along with this same order of grandeur figures, and illustrations. Nothing is left to the engineers are using the books as a reference set. of ideas, an even more astonishing spectacle imagination-there is no guesswork. The famous set is beyond a doubt the last word awaits the traveller who sets foot upon the Croft has been through the mill. His knowledge in practical electrical education. No one who of Saturn, the nearest one especi- of electricity has been gained by actual shirt -sleeve wishes to get anywhere in the electrical field can satellites contact with electrical He knows just afford to be without it. ally. Situated in the plane of Saturn's ring, problems. the observer would see only a bright bar r crossing the enormous globe of Saturn, but McGraw-Hill Book Co., Inc., in by excessively distorted dimensions per- Free Examination 370 Seventh Avenge, New York. spective, the whole system presenting very No Money Down Gentlemen-Please send me the CROFT LIBRARY different aspects than as seen from the OF PRACTICAL ELECTRICITY (shipping charges earth. Add to this the eclipse of a portion 10 Months to Pay ! prepaid), for 10 days' free examination. If satis- of Saturn by the shadow of the rings, the factory, I will send $1.50 in ten days and $2.00 per Fill in and mail the coupon attached and month until $19.50 has been paid. If not wanted, I phases of the enormous globe changing with we will send you the entire set of eight will return the books at your expense. (Write plainly the direction of 'the light from the sun, and volumes for ten days' Free Examination. You and fill in all lines.) we still have only a partial conception of We take all the risk-pay all charges. assume no obligation-you pay nothing Name the views that would meet our eyes. unless you decide to keep the books. Then "If it were possible to land on Saturn, and $1.50 in ten days and the balance at the rate Home Address of $2 a month. Send the coupon NOW and here the same doubt arises as in the case of see the books for yourself. Jupiter, the sky would have an appearance City and State equally strange. From different points of Employed by this sky, dotted with numerous the globe, Send the Coupon SI -3-28 moons, would be traversed by the luminous Occupation rings in varied aspects. TODAY 1034 Science and Invention for March, 1928 1000 NEEDED INVENTIONS Patent

1000 is a remark- NEEDED HEREable book for in- vice. INVENTIONS ventors. Nothing like it ever published before. Saves time. Saves Edited by work. Saves money. Tells you what inventions are needed now, Joseph H. Kraus and what is offered for them. Lists and de- c scribes the ONE THOUSAND NEEDED In this Department we publish such matter as is of interest to inventors and particularly to those INVENTIONS in these who are in doubt as to certain patent phases. Regular inquiries addressed to "Patent Advice" cannot fields: General Problems Automotive; Mechan- be answered by mail free of charge. Such inquiries are published here for the benefit of all readers. ical; Electrical; Chemical; Radio; Aviation; If the idea is thought to be of importance, we make it a rule not to divulge all details, in order to Marine. Extra chapter on the TEN MOST protect the inventor as far as it is possible to do so. NEEDED INVENTIONS. Should advice be desired by mail, a nominal charge of $1.00 is made for each question. Sketches, and descriptions must be clear and explicit. Only one side of sheet should be written on. FORTUNES IFORDEAS NOTE :-Before mailing your letter to this department, see to it that your name and address are This wonderful book may give you one idea upon the letter and envelope as well. Many letters are returned to us because either the name of that will win you a fortune. If you want to in- the inquirer or his address is incorrectly given. -vent-KNOW WHAT INVENTIONS WILL PAY YOU MOST. This book tells you. Compiled at great expense, and edited by Raymond Francis Yates, formerly Managing Editor of a leading STATIC DISPENSER A. 1. The electric brander suggested by you is scientific magazine. Over 100 pages durably bound. not a new idea and many of these articles are (1076) Albert Rosenstein, Savannah, Ga., asks merely your name being used today. It is doubtful if you can whether he can sell an invention before patenting secure a patent on such a suggestion, even if you SEND NO MONEY and address plainly it and also what we think of an idea for ground- writ ten and your copy of "1000 Needed Inventions" did use a thermostat to control the temperature of will ing any static electricity which may develop in the iron. be sent you immediately. Pay the postman only $1.25 a truck while gasoline is being poured into a plus postage on arrival. Money back aftex 10 days' A. 2. Every garage will show you a lift jack tank or which may be picked up by a motor provided with casters which can be rolled under examination if desired. Limited edition. 'write now. truck on a stormy day. He claims that it is bet- (Outside U. S. cash with order) a car and which by operation of the handle will $1.45 ter than the chain method, but he wouldn't di- raise the car. Two or three, or sometimes even BUREAU OF INVENTIVE SCIENCE vulge the principles to anyone. more of these can be found in any large garage DEPT. 73 ROCHESTER, N. Y. A. 1. There is of course no objection to selling in the cities and out of town districts. an idea before it is patented. If you know the A. 3. The automatic burglar alarm designed by party with whom you are dealing and he knows you is not entirely new and it is not a very you, and both of you are confident that you will feasible suggestion because sonic method must not cheat each other, by all means proceed with be provided for maintaining a pressure of air, `i the sale. and the windows of the bank or store must be You give us no idea conerning the construction double and quite firstly sealed to prevent escape of your lightning arrester; consequently, we are of that air. If there is any leakage of air, then not in a position to advise as to whether the sug- the diaphragm will close the electrical circuit in gestion is practical or not. but a short time. If the windows are absolutely Appertaining to your third statement, that you tight, it becomes quite impossible to change any would not divulge the secret to anyone, how do display which may be located within the air you suppose any manufacturer would be willing pocket and if double windows are provided at to undertake the purchase of your idea? The the outside, then condensation of moisture be- To The Man With An Idea action may he likened to purchasing a cat in a tween the two panes of glass can be cleaned with bag. You might know, but the purchaser would I offer a comprehensive, experienced, difficulty only. Altogether, the proposition seems efficient not, as to what he was getting. You might be- to us to be very unattractive. service for his prompt, legal lieve the cat to be worth $100.00, and the pur- protection, and the development of A. 4. The automatic cigar lighter is a little more his proposition. chaser himself hold that the cat is not even novel, but it is not a good plan because it takes worth $5.00. If you desire that your idea be quite a while for current to heat Send sketch, or model and descrip- sold, there is only one way to effect its sale, the coil, and the tion, for advice as to cost. Preliminary average individual purchasing his cigars in a and that is to give the purchaser every hit of cigar store is generally in a hurry to get advice gladly furnished without charge. information at You would to away. My experience and familiarity your disposal. have They want a light immediately, without having with divulge the invention to the patent attorney any- to various arts frequently enable nie 1.. wait even thirty seconds for it. This feature, way and likewise to the patent examiners. If however, is the best of the group upon which you accurately advise clients as to probab! it is not explained in its entirety, you cannot patentability before they go to an, requested information, but even this we do not expense. secure a patent. Every patent is so worded that consider to be very practical. We advise no those gifted in the art can understand and dupli- further action. Booklet of valuable information and form cate the invention. for properly disclosing your Idea, free on request. Write today. RECORDING AN IDEA IRVING L. McCATHRAN ELECTRIC STENCIL, AUTO JACK, BURGLAR Patent Lawyer ALARM AND CIGAR LIGHTER (1078) A. M. Baroody, Richmond, Va., asks how Formerly with (1077) C. P. Craig, Martinsville, Va., asks our he can record a patent be:ore proceeding to de- t opinion on the following: termine if the same is worthy of a patent. Richard B. ()wen 1. 1. An electric -heated stencil made in the form A. There is absolutely no way to record a 202 Owen Building, Washington, D. C. of a branding iron, on one end of which a die will patent. Years ago, caveats were issued by the 41V Park Row. New York City be found which twill burn the name of the manu- U. S. Patent Office, which permitted an inventor facturer into any wood articles made by the to protect his idea while he was working upon same. the same and before he had proceeded to apply 2. An automobile lift jack with casters on its for a patent on it. Caveats have been discon- base and provided with a long handle, so that it tinued because many ideas were being tied tip in can easily be put under a car. them and too many legal difficulties were encoun- 3. An automatic electric burglar alarm for store tered. Today the best thing to do is to establish windows, providing for an air space and a sensi- as many priority claims as cari possibly be estab- tive diaphragm located in this air space so that lished and then proceed with patenting, after if the window is broken, the escaping air will having had a search made. Several good methods WE COMMERCIALIZE INVENTIONS cause the diaphragm to close the circuit. of establishing priority are here given. Communicate with us If you have a patent to sell or 4. An electric cigar lighter with a gauze in the 1. Place detailed drawings and full descriptions wish to buy one. front of it so that when the cigar is pressed on one single sheet of paper. North American Finance & Development Corp. 2. A you Ouray Bldg.. opposite PatentOffice. Washington, D.C. against it, the heating coil will warm up and an statement that believe yourself to be electric bulb will flash on an advertisement. the original inventor should then he affixed to the bottom of the sheet of specifications and this should he sworn to before a notary public, who will affix his seal, stamp and date. 3. A duplicate of this same sheet, identically worded, should then he placed in an envelope and mailed to yourself. The envelope should be sealed PROTECT at the back with three seals, so that it cannot possibly be opened without breaking those seals. INVENTORS This envelope is not to be opened except in court to settle any lawsuits. Send for our Guide Book, HOW TO GET A PATENT, and Evidence of Invention 4. The first sheet is for your files. This should Blank, sent Free on request. Tells ire shown to as many friends as you care to trust our terms, methods, etc. Send model or with it and every time that anyone of their sees sketch and description of your irlyention the plans, they should affix their names to the for INSPECTION and INSTRUCTIONS paper and on the dateline put the date on which FREE. TERMS the invention was explained to them. The greater REASONABLE. BEST the number of names, the better is your pro- Name REFERENCES. tection. 5. Reduce the invention to practice; by that we mean to build a model. After you have built the Street model and have seen it work, take photographs RANDOLPH & CO. of it and have a notary affix his signature and seal on the back of each photograph. City Dept. 172, WASHINGTON, D. C. 6. Any method of tying up the date with the date of your conception establishes further priority claim. Science and Invention for March, 1928 1035

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All drawingsand spec. My Law ifications are prepar- Patent ed under my personal Offices supervision. Just Across Street From U.S.Pat. Office i

Agt Protect Your Ideas Take the First Step Today-Action Counts Inventors If you have a useful, practical, novel idea for any new article or for an improvement on an old one, you should communicate with a competent Registered Patent Attorney AT ONCE. Every year thousands of applications for patents are filed in the U. S. Patent Office. Frequently two or more applications are made for the same or substantially the same idea We7oe (even though the inventors may live in different sections of the country and be entirely unknown to one another). In such a case, the burden of proof rests upon the last application filed. Delays of even a few days in filing the application sometimes mean the loss of a patent. So lose no time. Get in touch with me at once by mailing the coupon below. Free Boo Prompt, Careful, Efficient Service This large, experienced organization devotes its entire time and attention to patent and trademark cases . Our offices are directly across the street from the U. S. Patent Office. We understand the technicalities of patent law. We know the rules and requirements of the Patent Office. We can proceed in the quickest, safest and best ways in preparing an application for a patent covering your idea. Our success has been built on the strength of careful, efficient, satisfactory service to inventors and trademark owners located in every state in the Union. Strict Secrecy Preserved-Write Me in Confidence All communications, sketches, drawings, etc., are held in strictest confidence in strong, steel, fireproof files, which are accessible only to authorized members of my staff. Feel free to write me fully and frankly. Your case will have my personal attention. It is probable that I can help you. Highest references. But FIRST-clip the coupon and get my free book. Do THAT right now. No Charge for Information On How to Proceed The booklet shown here contains valuable information relating to patent procedure that every inventor should have. And with it I will send you CLARENCE A. O'BRIEN my 'Record of Invention" form, on which you can sketch your idea and Registered Patent Attorney establish its date before a witness. Such evidence may later prove valu- 535 Security Savings Commercial Bank Bldg., able to you. Simply mail the coupon and I will send you the booklet, and the "Record of Invention" form, together with detailed information on how Washington, D. C. to proceed and the costs involved. Do this NOW. No need to lose a Please send me your free book, "How to minute's time. The coupon will bring you complete information entirely charge or obligation. Obtain a Patent," and your "Record of without Invention" form, without any cost or obliga- Clarence A. O'Brien tion on my part. Registered Patent Attorney Member of Bar of : Supreme Court of the United States; Court of Appeals, District of Columbia; Supreme Court, Address District of Columbia; United States Court of Claims. PRACTICE CONFINED EXCLUSIVELY TO PATENTS, TRADEMARKS AND COPYRIGHTS n .^ (Important-Print or Write name clearly) _ -.a,-,_,- _ 1 1036 Science and Invention for lllarcly 1928

Miniature Cities-How Built PATENTS (Continued from page 1030) TRADE-MARKS-DESIGNS FOREIGN PATENTS SOIL FOR MINIATURE SCENES The grain of the actual soil becomes im- MUNN & CO. mediately too coarse. Without its native EYS moisture and temperature it dries out and PATENT ATTORN loses its natural color. Under the necessity Associated since 1846 with the of miniature irrigation it becomes so much Scientific American mud. The exhibits placed upon it would Washington the Nation's Capital SCIENTIFIC AMERICAN Monument in become dirty and unsightly. And last but BUILDING not least, for purposes of visible effect, of countryside 24 West 40th Street soil seen over an expanse New York City PATENTS takes certain reflected hues from the spec- DON'T LOSE YOUR RIGHTS which disappear when the soil is placed SCIENTIFIC AMERICAN trum BUILDING TO PATENT PROTECTION on a miniature terrain, foreign to the at- of its Washington, D. C. Before disclosing your invention to mospheric and lighting conditions anyone send for blank form "EVIDENCE natural habitat. TOWER BUILDING OF CONCEPTION" to be signed and witnessed. As registered patent attorneys we Chicago, Ill. of inventors all over SOIL FURROWS WERE MADE represent hundreds HOW HOBART BUILDING the 1. nited States and Canada in the advancement of inventions. The form In this case the reflected colorings of the San Francisco, Cal. "Evidence of Conception," sample, in- district were studied in their true relation structions relating to obtaining of patents to VAN NUYS BUILDING and schedule of fees sent upon request. to the soil -color. The medium selected Los Angeles, Cal. imitate soil was Textone, a composition LANCASTER & in its application but will Books and Information on Patents and ALLWINE which is pliable Trade -Marks By Request 255 Ouray Building harden like cement in twenty-four hours. WASHINGTON, D. C. The furrows in the ground were reproduced Associates in all Foreign Countries Originators of forms "Evidence by means of a comb selected because the of Conception." teeth most nearly approximated upon the scale, the distance between the furrows in shade of coloring The better your invention is safeguarded by the orchard. The correct strong and comprehensive had been mixed and incorporated into the mix- Textone composition before grading the tile easier PATENTSand quicker it is to sell it profitably. A the base of the exhibit. The buyer wants protection as much as you Personal Service for ture upon do. As a former Assistant Examiner in the U. S. Patent Office, I oiler expert personal assistance from rough idea to finished patent - FIG TREES My Washington office assures you quick, efficient protection for IMITATING your invention. while my New York office is located in the INVENTORS world's greatest financial center and patent market. Your A study was made of the formation of inquiry puts you under no obligation. Necessarily the configuration of A. L APPLEBAUM. Registered Patent Attorney I maintain an unexcelled organization fig trees. Washington, D.C. 41 Park Row, New York, N.Y. and thoroughly equipped laboratories, to trunk and branches must be reproduced from 708 H St., render the following services. a natural but lasting plant, which carries I PREPARE APPLICATIONS for accurate resemblance to the Creator's STUDY AT HOME patents for filing in the United States an Become a lawyer. Legally trained originals. Many bushes were tried and dis- men win high positions and big and foreign countries. brittle since their twigs were too eidennt:atroiBnped. Ge opportuni- I PLACE INVENTIONS with re- carded, ties now than ever befcre. Big corpo- sponsible manufacturers, with whom I and perishable and not close enough in rations are headed by men with legal am acquainted, under arrangements that training. Earn are made profitable to the inventor. design. $5,000 to $10,000 Annually was found from the roots We guide you step by step. You can train at home dur- I SPECIALIZE in Electrical, Me- Finally a plant ing spare time. Degreegree of LL.B. conferred. LaSalle be selected innumerable off- students chanical, Chemical, and Radio Devices. of which could We furnishtoshrtttpracticing au x mne , includingi ineattorney. oróteeolefate, vumLaw Library. Low cost, easy terms. Get our valuable 108-page "Law I INVITE CORRESPONDENCE shoots each one bearing a perfect resem- Cuide" and 'Evidence books free. Send forthem NOW. with reputable inventors, Scientists, a fig tree. The roots of most LaSalle Extension University, Dept v3B4-L Chicagc blance to The World's Largest Business In5Nfution Chemists and Physicists, regarding their ; decidedly Training inventions and uncompleted experiments. plants are fibrous and enduring tough as compared with the part which H. R. VAN DEVENTER grows above the ground. As these were NEW YEAR - NEW IDEA Licensed Professional Engineer selected, cut and measured on the scale, Registered Patent Attorney on down the bench where PATENT YOUR IDEAS they were passed Call or send me a sketch of in shellac. 342 Madison Avenue, New York City they were dipped your invention. Phone LONgacre 3088 FREEInventors Recordin6 Blank SAW -DUST FOLIAGE Confidential Advice U. S. -and Foreign Patents secured by grade of saw -dust Reg.PatentAttorney For foliage a certain Z.H. POLACHE K immersed in light green dye As one of the oldest patent was selected, 1234 Broadway, New Yorker firms In America we give and dried in the sun. It was taken from the inventors at lowest consis- and dumped into a large re- PATEN tent charge, a service noted drying trays BLUE BOOK ON PATENTS for results, evidenced by many well-known Patente of extra- ceptacle, where it awaited the arrival of ordinary value Book, -Sense, free. the shellac treat- and Priority Record blank gratis. Lacey & Lacey, 644 F St., Washington, D. C. Estab. 1869 the tree -trunks which, after MONROE E. MILLER, PATENT' LAWYER, ment, had been dipped in silver gray coloring, 411-6 Ouray Building, WASHINGTON, D. C. representing the hark, dried, and then clipped ELECTRICAL AND MECHANICAL EXPERT into hot glue. Glistening with the hot glue colored Protect yourinventions and the trunks were plunged into the Trade -Marks today. Write saw -dust, which immediately clung to all of PATENTS for illustrated patent hook minia- and sketch sheet and terms free. BRYANT & LOWRY, the natural branches and twigs. The 314 Victor Building, Washington, D. C. PATENTS then set out to dry where BOOKLET FREE HIGHEST REFERENCES ture trees were PROMPTNESS ASSURED BEST RESULTS subsequently they were sprayed with two Send drawing or model for examination successive treatments of yellow and blue- MACHINE SHOP and advice. FOR GENERAL AND EXPERIMENTAL WORK green tint matching the natural colorings Mechanician in Electrical and Machine Work of all WATSON E. COLEMAN, Patent Lawyer Expert since D. C. fig leaves. Kinds, Models, Light Manufacturing. Established 724 9th Street, N. W., Washington, of 1878. Paul Hoenack 108 Park Row, near Chambers St.. All of the miniature buildings were New York City. Telephone, Worth 0910. lighted, being wired with small bulbs hooked - up in series. EDGAR M. KITCHIN INVENTIONS ' Miniature irrigation was introduced into Attorney and Counsellor at Law `o'mmercial-zed the exhibit, the water bubbling up out of Patent and Trade Mark Specialist 805 G. Street, N. W. Washington, D. C. ON A CASH OR ROYALTY BASIS the white stand -pipes seen in the center of PATENTED or UNPATENTED the photo. The exhibit was tilted slightly copy reaching you each month. Sub- In Business tiers ComP/e(efec/bUesreferences. Insure your 25 to provide gravity, the water being carried scribe to SCIENCE AND INVENTION --$2.50 14&MADAM FISHER MFG. Co.. off by means of a drain not visible in the a year. Experimenter Publishing Co., Inc., 230 Fifth Avenue, New York City. 205D Enright Ave. St. Louis, Mo. display. 1037 S< ienc c and Invention for March, 1928 a Flying Blind TCOPY S (Continued from page 1031) PAT ENTS RtIGNTS The English airport at Croydon may be FOR THE OTECTION flown into by the new flight system, Tempel- OUR OFFER:ER: OF YOUR INVENTION hof at Berlin, and Le Bourget at Paris may now receive planes in complete fogs. By YOUR FIRST STEP. The inventor should throwing up illuminated balloons several write for our blank form-"RECORD OF IN- hundred feet at each corner of the field, by VENTION." This should be signed, witnessed, guiding the airplane with radio beacons to and returned to us, together with model or the vicinity of the balloons, and then by for speaking with the pilot over radio tele- sketch and description of the invention phone, informing him of just how much INSPECTION and ADVICE FREE! clear space he has under the fog which covers the field, the plane may safely be brought in. The same schedule of conduct Our FIVE Books Mailed Free to will bring a plane in even if the fog completely covers the field, but the Navy has Inventors recently developed a method of fog dissi- Our Illustrated Guide Book pation to an altitude of approximately two dozen feet, which, when it is applied to air ports, will insure at least 24 feet of clarity HOW TO OBTAIN A PATENT over the field, and the pilots can be so informed by radio telephone. Only when a Contains full instructions regarding U. S. Pat- plane would be maneuvering to land would ents, Our Methods, Terms, and 100 Mechanical the device be operated; or when planes were Movements illustrated and described. taking off. However, these efforts on the ground are but adjuncts to the Ocker -Myers flying system, which involves only activities OUR TRADE -MARK BOOK in the air when pilots are flying blind in fog or on dark nights, when heavenly and earthly Shows value and necessity of Trade -Mark Pro- lights are not visible. tection. Information regarding Trade -Marks and unfair competition in trade; HOW THE PILOT "FLIES BLIND" The Ocker -Myers system employs no instruments not already devised and in use on OUR FOREIGN BOOK the better -equipped aircraft. It involves al- have Direct Agencies in Foreign Countries most solely a mental principle, and pilots are We instructed not only to use the instruments as and secure Foreign Patents in shortest time and indicators, but to use them in a concentrated at lowest cost. manner, carefully and sternly refusing to listen to their own instincts, or to what they think their plane is doing in a fog. The pilot PROGRESS OF INVENTION must educate out of himself every tendency Description of World's Most Pressing Prob- to react in a fog to what he feels he is doing, and react only to the instruments. He lems by Leading Scientists and Inventors must not take his eyes off the bank and turn All Communications and Data Strictly indicator, when the fog is once entered, ex- Confidential. Interference and Infringe- cept for extremely rapid glances to his fuel, Suits Prosecuted. air speed, altitude, rate of climb and compass ment meters. He must return his eyes to the bank and turn indicator at once, and concentrate on it-for, curious thing, no vertigo or sick- IMPORTANT ness will he feel so long as he concentrates TO AVOID DELAY MAKE YOUR CASE SPECIAL. YOU SHOULD on this artificial horizon, after all sight of HAVE MADE SPECIAL IN OUR OFFICE to save earth and heavens is gone. However, this YOUR CASE concentration is not absolutely necessary so corresp ondence, secure protection and early filing date in the long as he can see a star or a beacon on the Patent Office. To secure special preparation of your case send earth, though he could, of course, continue $25.00 on account with model or sketch and description of your to fly if he wished, without looking to earth invention. or sky, but by simply concentrating on his instruments. He could do this, but it is al- Our Lawyers Practice in all U. S. Courts and defend Clients in Suits involving ways more satisfactory to get a reassuring Patents, Trade -Marks and Copyrights glance at some outside bearing point. OUR ORGANIZATION OFFERS PERSONAL SERVICE "NATURAL FLYERS" NOW TABOO By Experienced Patent Lawyers, Solicitors, and Draftsmen It has come to instrument flying pure and as our best advertisement, and simple, and already the Pacific Air Trans- We regard a satisfied client port will turn down a pilot who declares he furnish, upon request, lists of clients in any state for whom flies by instinct. It is only. a matter of we have secured patents. months since even Army authorities favored the so-called instinctive pilot, he who "felt" Highest References-Prompt Service-Reasonable Terms the air, and was a so-called "natural pilot." WRITE TODAYm Habituation and liking for flying are still desired, but the pilots desired today, as a re- FREE ; VICTOR J. EVANS & CO sult of the new discoveries in the human COUPON Registered Patent Attorneys mind, must be men capable of turning to the instruments and auto -hypnotizing themselves MAIN OFFICES: 715 Ninth St., Washington, D. C. away from their instincts. BRANCH OFFICES: 1007 Woolworth Bldg., New York City; 518-519 Liberty AIR FATALITIES DUE TO "EAR CANALS" Bldg., Philadelphia, Pa.; 514 Empire Bldg., Pittsburgh, Pa.; 1114 Tacoma Bldg., A simple human misconception, as readily Chicago, Ill.; 1010 Hobart Bldg., San Francisco, Calif. correctible twenty years ago, as now, has Gentlemen: Please send me FREE OF CHARGE your books as described above led more than two thousand air navigators to their deaths. It is the gigantic misunder- Name standing of the human vestibular, or semi- circular canals in the inner ear, as a balanc- Address (Continued on page 1050) BIM -----RRMI- Mill ------BM--a 1038 Science and Invention for March, 1928

The Metal Emperor By A. MERRITT Get Your Copy (Continued from page 1001) Now! or small, and no matter how many, that doesn't by this time know all about us." "That's true," I nodded. "We'll probably be received with demon- strations of interest by the populace as wel- said MEN come guests," Drake. "Probably we'll WANTED find a sign-'welcome to our City'-hung up I can place 20 to 40 mall over the front gate!" day, in obs, while attar. Ruth smiled, a trifle tremulously. NlvrnngJdr before u hus- oul unBok.Nov. 3 "We'll come back," he said. He put his {pearn about, hands on her shoulders. "Do you think there the Dig pay. Biggest Alead r' is anything that could keep me from coming lotion ta s Business. That'. Businesses he Greer Cok back?" whispered. lege selected these Fields in World "Well," I broke in, "we'd better be start- d only Basso. Electricity, Autos, Co upon brings - ing. I think as Drake does, that we're tabu. you mazi Aviation now pay hun- eg dredsof Greer trained men Barring accident, there's no danger. And if up to $200 a week. Here I guess right about these creatures, accident are the 3 World's great - is impossible." oat businesses. Billions -not millions, but bil- "As inconceivable as the multiplication lions of dollars are spent table going wrong," Drake assured her. in them every year. And so, quickly, we made ready. Choose one of these three Our rifles now. would be worse than useless, so too our Practical pistols. Canteens filled with water, a couple Be Greer Trained of emergency rations, a few instruments, in - Greer trained men are needed. I have made hundreds of $10,000 a year men. Radio 90,000 in the last 26 years have come to Greer. Station WRNY Advice N EW YORK 326 METERS - 920 KILOCYCLES and 2XAL, 0.90 METERS for all! is owned and operated by the publishers of this magazine Set Construction-The New Shielded Only 3 Months Our Editors will talk to you LR4, The Loftin -White Constant - several times every week - Coupled Receiver, The Radio News Learn in Only 3 Months in Great Batteryless Receiver, Greer Shops on Large Live Equip- See your kewspaper Superhetero - ment. I'll Pay Your Fare Here, for details dynes, Neutrodynes, dozens of cir- FREE of extra cost, then help you to TUNE IN ON cuits of all sorts, with diagrams and a Job While Learning. Then I not complete instructions for building. only Fit You to get the Big Pay Job, WRNY but I'll help YOU HOLD IT. Young Construction of batteries. and Old, Educated and Uneducated, In- Construction of Loudspeakers- experienced and Experienced have romf ship model to found Greer Shops training Easy, 36 -in. cone type. Fascinating and Valuable. The construction of anything in Radio-from dials to wave traps- Coupon Below eluding a small spectroscope, a selection from the most modern the medical methods. f r Brings You kit-all these we packed in a lit- r r \ Big FREE tle haversack which Drake threw over his Radio Helps of every sort, con- 1 é - -- e \ BOOK shoulders. cerning every radio part-Trans- , í - e I pocketed my compact but exceedingly formers, Tubes, Shielding, Amplifi- R. powerful field -glasses. To my poignant and .7. cation, Alleviation of Static, How t*.. Learn everlasting regret, my camera had r 7 about been upon to Install Radio Equipment Per- ... 17 a mazing the bolting pony, and Ventnor had long been 1pportuni- out of films for his. We were ready for our manently, etc., etc., etc. ties in either d'g d Electricity, journey. J r Autos or Av- Radio News iation and Our path led straight away, a smooth Greer College. dark -grey road whose surface resembled ce- Amateurs' Handibook Learn Right now if you ment packed under enormous pressure. It at Greer act quick, I can glistened Don't let money hold make you a most un- faintly as though overlaid with 116 pages-fully illustrated you back. Get my usual short time offer. some vitreous coating. It narrowed abruptly Free Book. Find out Clip coupon now and into a wedged way that stopped at the It took Radio News to put this in- Now, howl Pay Your find out. Address me per- Fare Here, let You sonally-Erwin threshold of Norhala's door. valuable Radio Book before the public. Attend Either Greer, Pres. Days or Even- Greer College Diminishing through the distance, it It contains a series of selected articles ings, and help Electricity-Autos-. stretched straight as an arrow onward, and from Radio News, by the most you find Day Aviation vanished between the perpendicular cliffs or Evening 2024 So. Wabash Avenue, eminent of Radio Experts. Work to Pay Chicago, Illinois which formed the frowning gateway through Your Sopen - which we had passed the night before. ses while Erwin Greer, President Now SOLD EVERYWHERE learning. Dept. 3E, 2024 So. Wabash Avenue, as then, a mistiness checked the gaze. Then when Chicago, Illinois. ready we Send Free Book indicated below and Ruth with us, we made a brief inspection help you details of Special offer, without oblige find the tion to me. of the surroundings of Norhala's house. It real Big Autos Electricity was set as in Pay Aviation though the narrowest portion 50c Job. Name of an -glass. hour The precipitous walls Ii your dealer Fias none on hand Address marched inward from the gateway, forming write directly to the lower half of the figure. At the back, they swung apart at a wider angle. This EXPERIMENTER PUB. CO., INC. FREE BOOK upper part of the hour -glass was filled with a parklike forest. It was closed, perhaps 230 Fifth Avenue New York City twenty miles away, by a barrier of cliffs. 1039 Science and Invention for March, 1928

How, I wondered, did the path which Yuruk had pointed out to me pierce them? Was it by pass or tunnel, and if it was there why was it the armored men had not found and followed it? The waist between the two wedges was a valley not more than a mile wide. It was like a garden, dotted with flowering and fruiting trees, with gorgeous shrubs and fragrant lilies, and here and there a tiny green meadow. In its center stood the half - globe of blue that was Norhala's dwelling- an immense, bisected bubble of froth of molten sapphires and turquoises.. We had no time to study its beauties. A few last instructions to Ruth, and we set forth down the gray road. We had hardly taken a dozen steps when there came a faint cry from her. "Dick! Dick!" He ran back to her and caught her hands in his. "Dick," I heard her whisper. "Dick- come back safe to me!" His arms closed about her, hers tightened around his neck, black hair touched silken brown curls, their lips met and clung. In a little while he joined me; head down. silent, he strode along. The Spirit of Service IMPORTANT TO NEWSSTAND READERS An Advertisement of the order to eliminate all waste and un- INsold copies it has become necessary to Telephone and Telegraph Company supply newsstand dealers only with the American actual number of copies for which they have orders. This makes it advisable to place an order with your newsdealer, asking him to reserve a copy for you every month. Otherwise he will not be able to supply your copy. For your convenience, we are appending herewith a blank which IN JULY, 1926, lightning over an hour emergency we ask you to be good enough to fill in Arsenal telephone service was and hand to your newsdealer. Re will struck the Navy then be in a position to supply copies to at Denmark Lake, New established, invaluable in you regularly every month. If you are in interested in reserving your copy every jersey. The explosion demolished caring for the victims and month, do not fail to sign this blank. It the $8o,000,000 plant, rocked the mobilizing forces to fight the fire costs you nothing to do so. countryside, left thousands home- which followed. less and many dead. While the In spite of repeated warnings To Newsdealer community fled in terror, fresh of danger still threatening, no Address explosions hurled fragments of telephone worker left the affected Please reserve for me copies of shell and debris far and wide. area. SCIENCE AND INVENTION every month roster of those Through each of the day's until I notify you otherwise, and greatly High upon the oblige, who responded to the call of twenty-four hours, the spirit of Name duty were the telephone workers. service is the heritage of the thou- Operators in the danger zone sands of men and women who Address stayed at their posts. Those have made American telephone who had left for the day and service synonymous with depend- others on vacation, on their own ability. In every emergency, it A hundred yards more and we turned. initiative, hurried back to help is this spirit that causes Bell Sys- Ruth was still standing on the threshold of aside all the house of mystery, watching after us. She handle the unprecedented volume tem employees to set waved her hands, flitted in, and was hidden of calls. Linemen and repairmen thought of personal comfort and from us. braved exploding shells to re- safety and, voluntarily, risk their I'm glad, Drake," I said as we pushed on. store the service. Within a little lives to "Get the message through." "I've loved her since first I saw her"-he gripped my hand-"and she has me, she says. Told me that if she knew I really loved her, J she could make a better fight against- against what she calls the taint in her while we were away. That's why she did the pro- posing." He laughed. "A taint; A taint in that blessed angel! Still-she's afraid, terribly afraid, of something she thinks is in herself. I'll admit I thought the same way last night, but then I was shaky. It's nonsense-all damned nonsense !" I had no words to reassure him, for it Do you ray "who" when you should say "whom"? Do you say "between you and r" r. was not at all certain that Ruth's fear was instead of "between you and me"? no you mispronounce common words in your speech or use them incorrectly when you write? / INTERNATIONAL imaginary. Her terror and shame had been Many a man has been held down all his life and suffered untold embarrass- ... SCHOOL OF ENGLISH ment because of mistakes in of the too real, her description of her symptoms all You do not need to make English.Divisionthese mistakes any longer. Right at home, International Correspondence too clear to be hallucinations. Was it not in the privacy of your own room. you can make up the education you Schools missed in the days that you should have been at school. Dept. 6224-E Scranton, Penna. possible that she had been put by the senti- The International School of English will teach you, just / Without cost or obligation, please send nent Disc en rapport with itself and its peo- as it has taught thousands of other men and women, by me full details of your home -study course In a simple new method which shows you instinctively ENGLISH 1 ple? That she had been subjected to some which word to use and how to use it. I Name process of magnetization, not necessarily sin- Mail Coupon for Free Booklet ister, which produced in her a hypersensi- i Address tivity to its will and thought? ------Among our own kind we have this re- Insure your copy reaching you each month. Subscribe to Science and Invention-$2.50 a year. ceptivity-minds that react to each other Experimenter Publishing Co., 230 Fifth Avenue, N. Y. C. without the stimulus of the spoken word, 1040 Science and Invention for March, 1928

minds which are attuned ; and other minds unattuned, so that not even by the spoken or written word can our thought enter them. \Vhat mysterious currents are these along which the silent messages fly? Clearly, only something of the kind could explain Nor- hala's interchange of ideation with the Metal 45 STATIONS Horde. Ruth, unfamiliar with it, might well regard the sensitivity as a taint. Yet it might be of the greatest aid to us-and neither taint nor harmful to her, unless-unless- Broadcast I strove to ward off a dreadful thought! The walls of the gateway were close. The sparse vegetation along the base of the cliffs Bridge Lessons had ceased. The roadway itself had merged into the smooth, bare floor of the canyon. From vertical edge to edge of the rocky portal stretched a curtain of shimmering EVERY WEEK mist. As we drew close we realized that this was motionless, and less like vapor of water than vapor of light. It streamed in oddly Follow Every fixed lines like molecules of crystals in a Play with Ease still solution. \\ee passed within it, side by side. Any One of These Bridge Books Will Help! Instantly I knew that whatever these veils were, they were not moisture. The air we breathed was dry By WILBUR C. WHITEHEAD and electric. I was sensi- ble of a decided stimulation, a pleasant ting- Complete Auction Bridge $2.00 ling along every nerve, a gaiety almost light - Auction Bridge Standards 1.50 Auction Bridge Summary 1.00 By MILTON C. WORK Bridge Pointers and Tests $1.00 $5,000 for Contract Bridge 1.50 Auction Bridge Complete 2.00 Perpetual Motion $1.00 Foster's Contract Bridge The editors have received thousands of Ferguson's Contract Bridge .50 different designs of perpetual motion de- 100 Bridge Lessons .50 vices, and have received hundreds of cir- 2.00 cular letters soliciting finances for the Practical Auction Bridge building of perpetual motion machines. Shortcut to Standard Auction Bridge 1.50 The editors know that if they receive Auction Bridge (Annual Magazine) .75 these letters, there are thousands of others in this country who get similar letters and who fall for the claims made in the Prepared by Famous Broadcasters numerous prospectuses giving the earning capacities of the various machines. "Listeners in" need no introduction to Work and Whitehead. Most of the shares of stocks for these perpetual motion machines are being sold They are the most famous of Bridge Broadcasters, and masters at a rate of $1.00 per share, although some inventors are trying to sell shares of of the game. stocks at $100.00 per share. This is a selection- of their best books. Therefore the editors of this publication say, "Just come in and show us-merely Many of the plays that did not clear up in your mind over the SHOW us-a working model of a per- radio can now be studied at leisure. petual motion machine and we will give you $5,000.00. But the machine must not Whatever is to be known about Bridge will be found in these be made to operate by tides, winds, water- power, natural evaporation or humidity. books. These are books to fit every need and every purse. It must be perpetual motion." Pick your books now - and be assured that your knowledge will be coming from masters headed. \Ve could see each other quite Each book is well bound, printed in legible type, and contains plainly, the rocky floor on which we trod as anywhere from 160 to 500 pages well. But within this vapor of light there was no sound nor ghost of sound. Drake ORDER DIRECT turned to me, his lips moved in speech-and although he bent close to my ear, I heard CONSRAD CO., INC., 230 Fifth Ave., New York City nothing. \Ve stepped out into an opening, a pocket o i clear air. Our ears were filled with a high, shrill humming as unpleasantly vibrant as the shriek of a sand blast. Six feet to our right was the edge of the ledge on which we stood ; beyond it was a sheer drop into space, a shaft piercing down into the void Travel on and walled with the mists. But it was not that shaft that made us "Uncle Sam's" Payroll clutch each other. No! It was that up through it rose a colossal column of the RAILWAY POSTAL CLERKS COUPON > /'- cubes. It stood a hundred feet above the / FRANKLIN INSTITUTE level of our ledge, and its length vanished MAIL CARRIERS // Dept. A177 Rochester, N.Y. in the depths. Its head was a gigantic spin- ". Sirs: Rush to me, WITHOUT /i CHARGE. FREE 32 -page book ning wheel, yards in thickness, tapering at $1700 to $3300 Year with list of U. S. Government posi - its point of contact with the cliff wall into Many U. S. Government Jobs Obtainable / fions open to men and women and full SHOIIMIM particulars telling how to get them. a diameter half that of the side closest the MEN-BOYS, 17 UP MOÏCOUPON Name column, gleaming with flashes of green flame Steady Work No Layoffs Paid Vacations and grinding with tremendous speed at the Address face of the rock. Over it, attached to the cliff, was a vizored hood of some pale yellow metal, and it was ALL FREE this shelter that, cutting off the vaporous to yearg ar. Watch with chdn and ri large light like an enormous Eeatmaa Roll Film Camera or 22 sal. Hamilton aine. umbrella, made the for introducing finest assorted liquid perfume ut 15e Hoursbottle. aend for20bottleecnd shoo., gifteapoeoffer Inoue e.otaloe- We boat pocket of clarity in which we stood, the pou-iuotwrit° to BELL PERFUME CO., Dep.l(l-943 Chicago. 111. shaft up which sprang the pillar. Science and Invention for March, 1928 1U-t

Only an instant did the great wheel spin, the screaming rock melting beneath it, dropping like lava. As though it had received some message, its motion ceased. It tilted and looked down up us. I noted that its De ciricé grinding surface was studded thickly with the smaller pyramids, and that the tips of these were each capped with what seemed to be faceted gems, gleaming with the same pale radiance as the Shrine of the Cones. The column was bending : the wheel approaching- Drake seized me by the arm, and drew me swiftly hack into the mists. We were shrouded in their silence. We crept on step by step, feeling in fancy the prodigious wheeled face stealing upon us, and afraid to look behind us lest we step too close to the unseen verge. Yard after yard we slowly covered. Suddenly the vapors thinned and we passed out of them. A chaos of sound beat about us. The clanging of a million anvils. The clamor of a million forges. The crashing of a hundred years of thunder. The roarings of a thousand hurricanes. The prodigious bellowings of the Pit, beating against us as they had when we had flown down the long ramp into the depths of the seas of light. Instinct with power was that clamor. It ACTUAL PRACTICAL was the very choice of Force. Stunned, EXPERIENCE LESSONS blinded by it, we covered our ears and eyes. As before, the clangor died, leaving in its wake a bewildered silence. Then the silence began to throb with a vast humming, and through that humming rang a murmur, as New Yor kWhile of a rushing river of diamonds. And Enjoy Learning We opened our eyes, stared out, and felt awe grip our throats as though a hand had A BOVE is pictured a corner of one giving full information about the clutched them. I-1. of our two seven -story buildings. N. Y. E. S. Course and showing pic- We stood at the very rim of a wide ledge. of the We looked down into an immense pit, oval Here, actual work is accomplished and tures equipment available for shaped, thirty miles in length I judged, half practical experience is gained-plus a your personal use in our two seven - that as wide, and rimmed with precipices. thorough course in electrical theory, story buildings. IT IS ABSOLUTELY We were at the upper end of this deep val- under highly competent instructors FREE TO YOU. ley and on the tip of its axis. Its floor was who are themselves, Electrical Experts. five hundred feet below. The clouds of The New York Electrical School misty light that had obscured it the night New York Electrical School-this is before were gone, the air crystal clear, every a school noted throughout the world 29 W. 17th St., New York detail standing out with stereoscopic sharp- for its extensively equipped, modern ness. M AIL TOYAY First my eyes rested upon a broad band shops, and for the high standard of fluorescent amethyst, ringing the entire of electrical men released each year. The New York Electrical School rocky wall. It girdled the cliffs at a height The thousands who graduate arc 29 W. 17th Street, New York of ten thousand feet, and from this shining placed Please send me FREE 48 -Page booklet, zone fell the curtains of sparkling mist, the eagerly by the big electrical your It is understood that this nie enigmatic, sound -slaying the companies who recognize the real request puts under vapors. To no obligation. northwest they were pulsing like the aurora. value of men trained by the New and like the aurora they were shot through York Electrical School. with swift iridescences, spectrums, poly- Name chromatic gleanings. Always these were or- ACTUAL EXPERIENCE dered, geometric-like immense and flitting PRACTICAL LESSONS \iidres.i prismatic crystals flying swiftly to the very edges of the veils, then darting as swiftly THOROUGH KNOWLEDGE Town ... State away. Write today for the 48 -page booklet TEE METAL WONDER CITY From zone and veils the gaze leaped to the incredible City towering not two miles SCIENTIFIC MARVEL I Positively Guarantee LIGHTER-WINDPROOF. to increase your arms one -halt inch from us. in size, chest one full inch, strength Blue black, shining, sharply cut as though What Makes It Light? 25'";., health. 100% in one week's time, by following my instructions from polished steel, it reared full five thou- All guaranteed. Sample 25 cents and using my exerciser 10 minutes sand feet on high. it I Sample Gold or Sliver plated. $1.00 mornings and at night. Send $1 for How great was could Does the work of expensive Lighters. complete course and exercisers. Sat- not tell, for the height of its precipitous isfaction guaranteed or $1 refunded. Agents Write for Prices walls barred the vision. The frowning façade PROF. J. A. DRYER turned toward us, I five NEW METHOD MFG. CO. Box 1850-L Chicago, Ill. was, estimated, Box S.I.3 Bradford, Pa. miles in length. Its colossal scarp struck the eyes like a blow, its shadow, falling upon us, checked the heart. It was overpowering, gigantic-awesome as that midnight city of Mailing Lists MUSIC LESSONS YOUR HOME Will help you increase sales Dis that Dante saw rising within another Send for FREE catalog givingcounts and prices on thousands of classified pit. namesofrourbest proop tivecustom- -National, State an d Local--lndivtd- 4)'t JJJJI It was a metal city, mountainous. uals, Professions, Busluess Concerns. can read music like this quickly py Featureless and smooth, the immense wall Guaranteed Write today for our FREE BOOKLET. It tells how to learn 9 b reload of ¢each to play Piano, Organ, Violin, Mandolin, Guitar, Banjo. etc. heaved heavenward. It should have been Beginners or advanced players. Your only expense about blind, that vast oblong face-but it was not Sc per day for music and postageused. blind, and therein lay intangible terror. From AMERICAN SCHOOL of M USIC,57 Manhattan Bldg.,Chicago it radiated alertness, vigilance. It seemed to gaze toward us as though every foot were I Insure your copy reaching you each month. Subscribe to Science and Invention-$2.50 a year. Experimenter Publishing Co.. 230 Fifth Avenue, N. Y. C. manned with sentinels ; guardians, invisible 1042 Science and Invention for March, 1928

to the eyes, whose concentration of watchfulness was caught by some hidden sense more subtle than sight. It was a metal city, mountainous and- aware! About its base were huge openings-its gates, I thought. Through and around these portals swirled the Metal Horde, in units and in combinations, coming and going, stream- ing in and out, forming patterns about the openings like the fretted spume of breakers surging into the retreating from ocean -bit- ten gaps in some ironbound coast. From the immensity of the City the stunned eyes dropped back to the Pit in which it lay. Its floor was placquelike, an immense plane as smooth as though turned by potter's wheel, "I wishwe had broken by no mound or hillock, slope nor terrace. It was level, horizontal, and flaw- like him' lessly flat. On it was no green living thing more men -no trees nor bush, meadow nor covert. in "I've given him two promotions It was alive with movement ; seethingly, lE IL lE I! the last year and he's made good terrifyingly alive. Animate with a ferment ir VII S O N each time. as purposeful as it was mechanical ; a fer- "I always feel safe in moving him ment symmetrical, geometrical, supremely up because I know that he's prepar- ordered. ing himself to handle bigger work. The motion of the Metal Horde. Wonder of the Age "The International Correspondence Schools keep me advised of the progress he is making and I've encouraged him to keep on. His spare -time $21.000.00 It soon will be in studying certainly has made him a valuable man to this firm." for Spirits Dunninger, who writes exclusively for Why don't you study and get ready for promotion SCIENCE AND INVENTION Magazine full swing! too? We'll be glad to help you if you will only and who is the Chairman of our PSYCHI- make the start. And the way to do that is easy. CAL INVESTIGATION Committee, will Choose the work you like best in the coupon be- personally pay $10,000.00 to any medium or low; then mark and mail it to the International spiritualist who can present any psychical be a pioneer- Correspondence Schools today. This doesn't obligate manifestation in so-called spiritualism, you in the least, but it will bring you information that he will not explain or that he cannot that will help to start you on a successful career. reproduce by natural means. build your own This is your opportunity. Don't let it slip by. More than two years ago SCIENCE AND Mail the Coupon for Free Booklet INVENTION Magazine offered a prize of $1,000.00 to anyone who could demonstrate Excerpt from Science téi' Invention: his or her ability to communicate with the INTERNATIONAL CORRESPONDENCE SCHOOLS spirits or to give some definite form of a "Television may solve star "The Universal University" psychical which in itself Box 6222-E, Scranton, Penna. demonstration copy of was not trickery. secrets. Color images of planets Without cos or obligation. please send me a The result has been that mediums and Wins Id and particulars can be broadcast from observa- lsubject hebefore which have spiritual organizations have been afraid to about tithe Those weak at- Industrial Management 0Business Correspondence place proofs before us. tories and flashed in screen at Personnel Management Ila Show Card and Sign tempts which have been made to demon- Traffic Management Lettering strate psychical phenomena were almost distant points." Accounting and C.P.A. D Stenography and Typing instantly proven fraudulent, and no medi- Donald H. Menzel, Ph.D. Coaching Civil Service um has dared to contradict our findings. D Cost Accounting Railway Mail Clerk In view of these facts, should we not Lick Observatory. Bookkeeping Common School Subjects Salesmanship High School Subjects consider all mediums fraudulent? Secretarial Work Magazine and Book To the $10,000.00 which has been offered Scientific men the world over D Spanish D French Illustrator by Joseph F. Rinn through this publication D Advertising Cartooning for Spiritual proofs and the $1,000.00 in are directing their attention to TECHNICAL AND INDUSTRIAL COURSES addition offered by SCIENCE AND IN- this discovery of the Electrical Engineer Architect VENTION Magazine we now add Dun- age- Electric Lighting Architects' Blueprints Builder ninger's $10,000.00. Television. Everything points Mechanical Engineer Contractor and So now we have a total of of- Mechanical Draftsman Architectural Draftsman $21,000.00 to its becoming as world-wide Ei Machine 'raclice Concrete Builder fered for proofs of Psychical Manifesta- 0 Railroad Positions Structural Engineer tions. Spiritualists-get busy. as Radio. D Oas Engine Operating Chemistry D Pharmacy Civil Engineer Automobile Work Get into this interesting sub- Surveying and Mapping Airplane Engines Metallurgy Mining Agriculture and Poultry ject, and take an active part Steam Engineering Radio D Mathematics They moved beneath us, these enigmatic beings, in a countless host. They marched in the important experiments Name and countermarched in battalions, in regi- that are being conducted daily. Street Address ments, in armies. Far to the south I glimpsed In its infancy as it is, you may colossal shapes like mobile, castellated and City State unearth an important discovery pyramidal hills. They were circling, weav- that will reap a good profit. Occupation ing about each other with incredible rapidity dSaioatad oLn This book ALL ABOUT Itionall Canadian, imited, Montreal -like scores of the pyramid of Cheops - Correse pondencea crowned with turrets and come to life and TELEVISION-will enable you dancing. From the turrets issued vivid to build a fine workable set. flashes, lightning bright-and on their wake You -and This New Machine Can rolled the echoes of far -away thunder. 116 pages, 9 x 12, illustrated Earn OBELISKS A SQUADRON OF Start Now! $500 a Month Out of the north sped a squadron of n Operate a Tire RepairShop flamed and flared obelisks from whose tops 90,000,000 Tires in use. America's greatest opportunity for men the spinning wheels, appearing at that dis- 50c with small capital. We furnish everything-$100 and up. Easy tance like fiery whirling discs. on the newsstand payments. We train you FREE The Things lifted themselves up from right at home. Start making or use coupon money at once. Write today for their seething in a thousand incredible Free Book of Opportunity. shapes, shapes squared and globed and HAYWOOD TIRE EQUIPMENT CO. 1312 a. Oakley Chicago, Illinois spiked, and shifting swiftly into other thou- EXPERIMENTER PUB. CO. sands as incredible. I watched a mass of 230 Fifth Ave., New York, N. Y. Gentlemen: I enclose 50c. for one copy or them draw up into the likeness of a tent, TELEVISION. skyscraper high, hang so for an instant, then SAVE 60% ON DIAMONDS form into a dozen towering legs that strode NAME Import unmounted diamonds from Mexico-have them mounted by jeweler-save 60% of usual cost. We sell away like gigantic headless and bodyless only genuine diamonds. U. S. Customs appraisal is tarantulas, in steps two hundred feet long. ADDRESS proof of value. Sent C. O. D. No money in advance. I watched mile-long lines of them shape and Write for price list. interlaced lozengers CITY STATE BLOCK HERMANOS re -shape into circles, into Dept. 13-C Bolivar 15 Mexico City, Mex. and pentagons-then lift in columns, and Science and Invention for March, 1928 1043 shoot through the air in an unimaginable - barrage. And when the shiftings of the hordes permitted, we saw that all the flat floor of the valley was stripped and checkered, stippled and tesselated with every color; patterned with enormous lozenges and squares, rhomboids and parallelograms, pentagons and hexagons and diamonds, lu- nettes, circles and spirals : harlequined yet harmonious : instinct with a grotesque suggestion of a super -Futurism. But always this patterning was ordered, always coherent, as though it were a page on which was spelled some untranslatable other -world message. Fourth Dimensional revelations by a deity ! Commandments traced by a mathematical God! Looping across the vale, emerging from the sparkling folds of the southernmost curtainings and vanishing into the gleaming veils of the easternmost, ran a broad ribbon of pale -green jade ; not straightly but with Teed manifold convolutions and flourishes. It was New 1928 ,_Jacket Assembly like a sentence in Arabic. It was margined Five Thousand Red Jacket Craftsmen have made a bargain possible for you Without Waco eolee volume, no manufacturer could give the equivalent of - Waco Shop No. 12' at it. price-A Red Jacket Master Drill, the Waco Craftsman á Lotte, tho electric power tool,, the Jig Saw. the Red Jacket Bond Salo, or the Crafts Courere. and ie Aylward, known cratteman andmanufacturer who bao deaelov d ir te hobbyinto a coopm. eratie eeoiativot of five thousand craftsmen. Portable-!interchangeable-Complete HOME WORK SHOP The new 1928 Combination of Electric tool, brim;., you a Red Jacket Rand Saw and in addition the power. ful Red Jacket Master Drill Motor wit h direct drive to the Waco Cretteman'e wood turning lathe (capacity 9 in. 38 in.); bench saw that has depth and aide gauge.), scroll end jig saw; and all oeceeeoriee for both portable and stationary power drilling. buffing. grinding and cleaning. Attache. to any light eocket and coo. worts your work bench into a complete private tool and machine shop. It is n complete cheat f ull of electrically driven tools designed by a master for the private lover. and men who create, repair and appreciate handy toale at home. use of tool It Is Easy to Do These Things Write or send coupon at e for valuable information to all interested in beautiful handiwork. It is free. It tells you how easy it is to operate a Red Jacket eat of tools and (fate the adv otagee and privileges that are free to member oraftemeo. Don't all It sis free. You oreuinvited. The WACO GUARANTEE Look out fee imitationu.There If it is not what you want only ono Red Jacket--one Complete Only aliens you get if-send it back Waco-ono Wm. I. Aylward. Mastercrafteman. Special Crafts Course FREE SPECIAL CRAFTS COURSE and blueprint service is free to Red Jacket Sires owners- oll that there i s to know about handicraft methods, r materials, ods, awing. /1)00 sawing. turning, designing.. ccarpentering. wdecorating, io taught by special correspondence. Buy on Your Own Terms Down down. Li ecounte cash. Only It monthlya10.00payment plans. Itrie malr hardship ot oown a 10 DAY FREETRIAL Tilt Ton Jacket. This Head. Table stock for. SEND THE COUPON"" niched where eleetricbloiity WACO TOOL WORKS, Inc. is availo 542 N. Parkside Ave, Chicago Manager, Dept. 203. Please send me RED JACKET all free information and literature on MASTER DRILL Red Jacket Assemblies. The elaborate and minimalneollmt Name ever designed se deivtoe power. Address 1zI Same Size as THE NEW 0 $7 $875 rip, ¶ 5O IMPROVED JINK "PENCIL POINTEO_PEN'_ FOUNTAIN The Perfect Writing Instrument PENS a lead No better materi- Writes with ink free and easy as pen. als or workman- cil without a miss, skip or blur. Won't MAKES¡ ship in pens cost- blot, scratch, leak or soil hands. 3 to 4 CAR- The pillar leaned over. The floor of the valley ing many times BON arose to meet us. Further and further over its price You'll never use a fountain COPIES leaned the pillar. Again we were shifted to pen once you try an Ink- With Original in Ink' another surface of the crowning cube. Swifter, ograph. No complica- Patent Automatic 14-kt. Gold! the valley floor swept up toward us . . . ted mechanism Feed prevents clogging-steady uni -1 to get form flow of ink actually improves your, out of handwriting. Any one can write with your Inlo-i That hard amooth order, of can bend, with sapphire blue. Along its twisting course ball -like 14 -kt, gold ograph-no style writing point which makes distort, or injure its 14 -kt. gold DEALERS Ink. ov spread, Send For two broad bands of jet paralleled the ceru- coarsest point. Inkograph also made in smaller size with by ring on cap for men's watch chain or ladies' soutoir Catalogue lean shore. The ribbon was spanned l', n wiwrapid- Nor were sc Pay Postman $1.50 .plus postage or sent prepaid if remittanse scores of flashing crystal arches. lead SEND accompanies order. Year a guarantee certificate assures absolute these bridges-even from that distance I pencil NO MONEY satisfaction. Your money back if not satisfied within ten days. knew they were no bridges. From them came INKOGRAPH CO., Inc., 199-301 Centre Street, New York City. the crystalline murmurings. Sell Inkogra he, make bigger profits, more sales, without investment. Quicker commissions, popular Jade? This stream jade? If so, then it AGENTS prices, nocolleeting, no competition. Send for an Inkograph or write for special sales plan booklet. must be in truth molten, for I caught its swift and polished rushing. It was no jade. Travel On Railway Postal Clerks It was in truth a river; a river shaped and prisoned into this semblance of a writing "Uncle Sam's $158 to $225 MONTH across the patterned plane. Men -Women 18 up ---Mail coupon before you lose it I looked upward-up to the circling peaks. Pay Roll They were a stupendous coronet thrusting Franklin INSTITUTE, Dept. A182 miles deep into the dazzling sky. In color Rochester, N. Y. they were an immense and variegated flower Sirs: Rush to me, without charge-copy of 32- / page book, How to Get U. S. Government Jobs," with countless multiform petals of stone; in / with lists of positions obtainable and full particular outline they were a ring of fortresses built / telling how to get them. STEADY WORK-NO LAYOFFS-PAID VACATIONS by fantastic unknown Gods. Up they thrust / Name -domes and arched, spired and horned, Many Government Jobs Open to Women / pyramided, fanged and needled. Here were Common Education Sufficient / Address palisades of burning orange with barbicans of incandescent bronze; there aiguilles of Insure your copy reaching you each month. Subscribe to Science and Invention-;2.50 a year. l azure rising from bastions of cinnabar red; Experimenter Publishing Co., 230 Fifth Avenue, N. Y. C. turrets of royal purple, obelisks of indigo; Science and Invention for March, 1928

vermillion, with citron yellows, and with rust of rubies; watchtowers of flaming scarlet. America's Most Famous Scattered among them were the flashing , emeralds of the glaciers and the immense , 4 9/4 FP Brief Cases baroques of the snow fields. A- Like a diadem, the summits ringed the oval valley. Below them ran the ring of flashing amethyst with its auroral mists. Under them stretched the vast and patterned flat, covered with still symbol and inexplic- able movement. Their summits brooded upon the blue black, metallic mass of the watchful City. «« Within encircling walls, over plain and the dawnin y over that City hovered a spirit not to be understood by man. It was like an emana- Anew field for tion from stars and space. men Down from the ledge where we stood fell a steep ramp, similar to that by which, in 3 the darkness, we had descended. It dropped at an angle of at least forty-five degrees ; instructive books its surface was smooth and polished. "Hell!" Drake emerged from his trance of wonder into practicality. "We can't walk PRIG': that. Once we get started-there isn't a YOURS drys ABSOLUTELY FREE! traffic cop on Long Island who could catch $5.00 New! mproved "Versatile" now has 6 pockets instead of 5. No increase in price. Combines Brief Case, Week- up to us." End Case, Traveling Bag, Sample Case, Catalogue Case, 700 Pages Accountant's Case-- 6 bags practically for the price of one. 17 -inch size, top grain selected COWHIDE. 500 Illustrations Patented Steel Bar Construction prevents edges from sagging, curling. Retains smart lines ALWAYS! COLORS-Handsome Brown and Black. Rules for Model Contest Contents of each chapter- pocket, cleverly hidden: for valuable papers, bonds, (Continued from page 1006) I. Aircraft Types. II. ASecretreports, contracts, precious manuscripts, money, etc. Lighter - than - Air Craft. 1. A handsome trophy cup engraved III. Early Airplane De- B Pocket containing removable Toilet Kit. with your name, will be awarded as the signs. General Design Toilet Kit. (See illustration over Brief Case.) prize for the best model submitted during Considerations. IV. De- C Fold up the month. The decision of the judges will sign and Construction of Semi -Stitt partition: for sketches, drawings, catalogues, be final and will be based on: A-nov- Aerofoils. V. Arrange- D magazines, stationery, order books, etc. elty of construction; B-workmanship; C- ment, Fabrication and Bracing of Airplane Wings. VI. Pouch Pocket for Pens, Pencils, Erases, etc. operating efficiency of the model as related Airplane Fuselage and Landing Gear Construction. E to the efficiency of the device which the VII. Airplane Power Plant Types and Installation. flap-when down, spreads FPatented, disappearing pressed model simulates, and D-the care exercised VIII. Aviation Engine Design and Construction. bottom and prevents case from tipping over. No need in design and in submitting to us sketches Air -Cooled Engines. IX. Aviation Engine Design to lean it against chair, wall or desk-it CANNOT and Construction. Water -Cooled Engines. X. Avia- tip overt Thhi Hap also extends pocket ' (F) to great and other details covering the model. width for shirts, collars, socks, ties, extra trousers, un- 2. Models of all kinds may be entered. tion Engine Auxiliaries. XI. Aircraft Propeller derwear, etc. They may be working models or not, ac- Construction and Action. XII. Airplane Equilib- Utility pocket for odds and ends -6 pockets in all! cording to the subject that is being rium and Control Principles. XIII. Uncrating, Set- G You simply MUST see the "VERSATILE" case to handled. ting Up and Aligning Airplane. XIV. Inspection and appreciate it! of Engines. XV. De- 3. Models may be made of any available Maintenance Airplanes and is tails of Modern Airships and Airplanes. XVI. Sea- EXECUTIVES enthuse over "VERSATILE" material, preferably something that planes, FINing Boats, Amphibians and Other Air- We supply the "VERSATILE" to business men, bankers cheap and easily obtainable. craft. XVII. Some Aspects of Commercial Aviation. brokers, traveling men, accountants, secretaries, salesmen 4. Models must be submitted in all cases. XVIII. Aircraft Instruments and Aerial Navigation. clergymen, architects, attorneys, students, young men and Good photographs are also highly desirable for Aeronautics, women. It is smart looking, "hobby," English and where the maker does not desire the XIX. Standard Nomenclature tailored style. n ofect Report No. 240, Part I. realStamps0Briefr CaceceOu model to be taken apart, legible drawings pport A "D 1 with all dimensions covering parts that This book is written in simple, understandable by Mail" price 49 5 lang uage. Send No Money! Pay NOTH- are not accessible must be submitted. i `i ING on Delivery! Use" Versa - 5. Models should be securely crated and "s.w `tile" Brief Caae for 10 Days protected against drainage in shipment AVIATION absolutely FREE! It pleased and sent to us by parcel post, express or you may pay on Budget Plan: ENGINES 54.00 MONTHLY freight prepaid. Models will be returned or, if you wish to pay cash at end when requested. This treatise, written by a of 10 DAYS, deduct 51.20 and send 6. Models for entry in any particular con- recognized authority on ail Check or Money Order for 513.75 in of the practical aspects of FULL SETTLEMENT. Otherwise $ test must reach this office on or before internal combustion engine return it. Order NOW the 25th of the third month preceding date construction, maintenance, of publication. For instance, models for and repair, fills the need the May contest much reach us on or be- as no other book does. SEAVER-WILLIAMS CO. The matter is logically Importers, Exporters, National Mail Order House fore the 25th of February. arranged; all descriptive mat- "Two Generations of Honorable Dealings" 7. Address all entries to Editor Model De- ter is simply expressed and 365 WASHINGTON STREET, BOSTON, MASS. partment, c/o Science and Invention Mag- copiously illustrated, so that Sole Distributors of "Versatile" Brief Case azine, 230 Fifth Avenue, New York City. anyone can understand air- Gentlemen-Send me "Versatile" Brief Case for 10 plane engine operation and Days' FREE Trial on the above plan. Color desired repair even if without previous mechanical training. This work is invaluable for Name anyone desiring to become "Maybe there's another way," I began- an aviator or aviator mechan- Address ician. Clip and mail this Adv. NOW! Please ten us some- and was still. thing about yourself. We will appreciate and respect Through the mists shining block peeped 274 PAGES PRICE_$1.25 Information. THANK YOU! S.I. 3-2.4 a the us. V at It paused, seemed to perk itself, and ixi,viwi,vwwilk spun so that in turn each of its six faces A. B. C. OP took us in. AVIATION I was lifted upon it by multitudes of lit- THE MIDGET SLIDE RULE This book describes the basic instantly adds, subtracts-'-'mul- tle invisible hands. Drake was whirled up principles of aviation, tells tiplies, divides, solves propor- beside me. The block swept away from the how a balloon, or dirigible is tion, gives all roots and pow- made, and why It floats in the ers. Logarithms, Sines, Cos- ledge and swayed for a moment. Under us, air. Describes how an airplane ines, Tangents, Cotangents, etc. flies. It shows in detail the. Also gives decimal equivalents, as though we were floating in air, the val- different parts of an airpianet lettered and numbered drill and ley lay stretched. There was a rapid re- what they are, and what they tap sizes. do. Describes all types of air- More than 110,000 sold, more adjustment, a shifting of our two selves planes and how they differ in than 2,000 unsolicited testi- construction, as well as de- monials. The Engine -divided upon another surface. I looked down upon tailing the advantages and scales are en white finished aluminum and are grease and a tremendous slender pillar of the cubes, disadvantages of different waterproof. Diameter 4'. Price with Instruction Book, types of aircraft. It includes a $1.50. Pocket Carrying Case. 50e extra, Cash or C.O.D dropping five hundred feet to the valley's complete dictionary of avia- Catalogue free. Your money back if you are not satisfied.' ; tion terms and clear drawings floor a column of which the block that held of leading airplanes. G ILSON SLIDE RULE COMPANY. Stuart, Florida us was the top. Although the whirling wheel that had PRICE $1.25 crowned it was gone, I knew the column for CHEMISTS the Grinding Thing from which we had Remit by cash, stamps, check, or money order. Our new catalog, listing 5,000 fled. The questing block had been its scout. No C.O.D.'s 2,500 illustrations, Lab- Chemicals, It had sought us out through the mists, had We Pay Postage On All Books oratory Apparatus and 1,000 books, caught us and delivered us! sent on receipt of 50e. The pillar leaned over. The floor of the LABORATORY MATERIALS CO. valley arose to meet us. Further and further CONSRAD COMPANY, Inc. 635 East 71st St., Chicago, U.S.A. over leaned the pillar. Again we were shifted 230 FIFTII AVENUE NEW YORK Science and Invention for March, 1928 1045 to another surface of the crowning cube. Swifter, the valley floor swept up toward us. There was a little shock. We stood upon the floor of the Pit. And breaking from that which had carried us there came score upon score of the cubes. They broke from it, disintegrating Solve this Puzzle it. They circled about us, curiously, inter- The letters on the wing of this plane show the estedly, twinkling at us from their deep number of miles Lindbergh flew from New York to Paris. The letters in the alphabet are num- sparkling points of eyes. bered-A is 1 B is 2 etc. Put down the number Then suddenly I was lifted once more and represented by each letter (C F A I) in the order they appear and you will have the number tossed to the surface of the nearest block. of miles Lindbergh flew from New York to Paris. Can you work it out? Send your answer today-no ebllgation or cost to you now, later, or ever. Be wies AND WIN BUICK^r l am going to give this beautiful new 1928 four door QOO Cash Buick Sedan, also a 1928 Nash Sedan also a 1928 Essex Jr0 Sedan, also a 1928 Chevrolet Sedan-four cars and a / large list of additional costly prizes-over $5000.00. Cars will be delivered free to winners by nearest auto dealers. I have already given over fifty new automobiles to advertise out business and now YOU can get this new Buick Sedan or cash if you wish. You can win it. It costs nothing to try. First prize winner can have Buick or cash value of car ($1295.00) and s50522 EXTRA For Promptness! B. prompt-Mat figure out what number each letter on the wing of the plane represents. Put them down In order shown. Mail me your answer with your name and address. That's all. Send no money. No obligation. All who answer van share In cash and prises. In case of ties duplicate prises given. Everybody rewarded. Hurry) 8605.00 cash extra for promptness. T. W. Nally. Mgt.. Dept. 493 600 No. Dearborn St.. Chicago. IL Physical Training for Height Increasing Results have been remarkable. My scientific physical training course and apparatus have for their special object the increase in height, as well as improved health, buoyant pep, and better appearance. To he of full height means more efficiency and ability to increase your earning power. I have no drugs, dope, or medicines to sell, but a new apparatus I have invented, with scientifically arranged exercises, and special instructions, which will take only a few minutes of your time each day. Civilized habits cause a flattening of the "I have gained in height since takln« your Course (two vertebrae and their cartila- months ago.) I am a real man now and can't recommend your Course too highly. it is just wonderful. My age ginous pads. My apparatus is 22 years. I am today one of the greatest ball players builds up and expands the spinal in the country, but the lack of size held me down In past column, at the same time years, but your Course helped me greatly. I can hardly strengthening the muscles which give you enough praise." D..l., S1.1,07113. Mo. of the stopped. . . Slowly, hold the vertebrae in posi- I started your Course in Scientific Height Increasing a The cataract globes month ago, and I can say that It Is wonderful. I have they advanced. We were pushed forward, tion. Thus with increased followed all your instructions, and made the exercises lifted by that force which I can always only room the bones and the cartila- according to the same. I have increased In height liken to myriads of tiny invisible hands. The ginous pads separating them are considerably and gained 10 pounds. Please send shining arcs of their backs undulated be- permitted to expand to the me my nest lesson." If. B., Miami, Fla. neath us. fullest degree. Results are permanent because of the muscular strengthening which takes place concurrently with the expansion. Nerves searched and blood vessels to and from the spine are then no longer impinged upon, con- I spun upon it while its tiny eyes sequently, you get fuller and more abundant health and physical fitness, and the me. It tossed me to another. I caught a maximum height is attained. My Course is easy, inexpensive, and results sure! glimpse of Drake's body drifting through Write today for FREE information the air. The play became more rapid, breath -tak- L. GLOVER Dept. A-97 SAUSALITO, CALIF. ing. It was play-I realized that. But it was perilous play for us. I felt myself as fragile as a doll of glass in the hands of o careless children. Powerfuif&7' Ú1b2 A score or more of the cubes merged, and clicked into an obelisk form that tossed me a hundred feet of space. As I flew, S across R 1 tiipetsSóffereá I saw that there were now thousands of the B/G NEW Metal People crowding about the spot of Ff W Ultra Selective which we were the nucleus. Their squared BATTERY and curved and angled surface gleamed like Or pale blue steel. I caught a glimpse of other .011 .1M1 eagg Delighted thousands report Mirare'. get programs SPECIAL Mirase comes completely assembled, rigidly hundreds raising themselves from the throng Coast to Coast, aleo Canada, Cuba, Mexico, with Operdatand WHOLESALE onr11Mirraavo withb eries orFROM in pillars and fan -shaped columns, thrusting magnificent, clear cathedral tone. Built like latest PRICES ELECTRIC DOUSE CURRENT-ast you pro- $200 sets-don't confuse with cheap "Squawky" to seer -agents f er. Choice of beautiful consoles (with built themselves up to look at us. radios. Unless 80 days' trial proves roar Siraco who in thephonic typespeakers) or table cabi- the MOST SELECTIVE, RICHEST, FULLEST t tofriends nets. Insure complt satisfaction and save er A globe came coursing along. It TONED and MOST POWERFUL DISTANCE GET- ice much n oy et.. kern, tubes, fornaemodel great batteries orA, Ka d C li ht sacket power uni4 COMPLETELY stopped, abruptly. In mid-flight I was TER among highest grade aete,don't bay itl Every COUPONMAIL S -deal direct with one or America'. oldeetreli- ASSEMBLED STRATED able makere of fine radios (8th succesefulyea». (8 Tube16925t checked and drawn downward, and then CATALOG /gismo) YeeBEAUTIFUILYILL ijot sonumow mmmmmmm-mmoff a foot above the surface of this s OFF MIDWEEST RADIO CORPORATION, Pioneer Builders of Sets hung poised F(Rdio 409E Miraco Bldg., Cincinnati, Ohio force it wielded held ,yl; wrt'HOUT' OBLIGATION d free literature, AMAZING sphere. The unknown guitas SPECIAL WHOLESALE PRICE OFFER, testimony of nearby it beneath me, ex- Ccast tp mere, etc. me suspended while spun -.coast »', amining pie. NAME ir!Ì 30 DAYS FREE TRIA I was tossed to another waiting cube, and ADDRESS the globe spun away. On the ground, not ten feet from me, was Drake, face white, swaying dizzily. One of the great gateways MECHANICAL ENGINEERING of the City was close. Suddenly the cube MECHANICAL Engineering embraces the design, construction and me its grip, tightened it Learn at home operation of machines and machine tools. It is a profession which that held tightened offers almost unlimited opportunities to men who combine 11 so that it drew me helplessly down upon its chunical ability with technical training. Before I dropped, Drake's body One of the best ways to train yourself to secure a' surface. position as a Mechanical Engineer is through the leaped toward me as though drawn by a home -study courses of the International School i of Engineering. INTERNATIONAL I lasso. He fell at my side. These courses are complete, up -to- SCHOOL Then, like a mischievous boy bearing off date and especially arranged to/ OF ENGINEERING meet the needs of the student spoils, the block that held us raced away, who studies at home. They Division of the Correspondence Schools open portal. A blaze of are particularly helpful International Penna. straight for the because they are writ -.....0. - Dept. 6223-E, Scranton, incandescent blue blinded us, and again as ten by well-known Without cost or obligation, please send me I mechanical full details of your home -study course in the glare faded Drake lay beside nie-a engineers. skeleton form. Swiftly flesh melted back f' MECHANICAL ENGINEERING upon him, clothed him. t^me Mail the Coupon for Free Booklet ,00°. The cube stopped; the unseen hands raised Address us, slid us gently over the edge and set us 1046 Science and Invention for March, 1928

upright on the floor. The cube sped away. All about us stretched another of those vast halls in which burned on high the pale - gilt suns. Between its colossal columns streamed thousands of the Metal Horde, no longer hurriedly, but quietly, deliberately, sedately. We were within the City-even as Ventnor had commanded. CHAPTER IXX. Is your pay check big enough for all THE CITY THAT WAS ALIVE the things you need? Can you afford a few luxuries? ... If youareame- CLOSE beside us was one of the chanic, salesman or clerk, if you work for a living and don't make it, cyclopean columns. We crept to it, get in touch with me and I'lltell you how other men LIKE YOU have and crouched at its base opposite the solved the problem. If you are will- drift of the Metal People. We felt like ants ing to work, if you can furnish a character reference or two, we willset you in that tremendous place, the weird luminaries up as our representative and equip you to meet and beat all competi- gleaming about it like garlands of frozen tion in men's clothing. One sale a suns, the hosts of animate cubes and spheres day means 930.00 a week-extra! and pyramids trooping past. These ranged "$100 amweek"saysade O. W0 Martin neverok over a k until I in size from shapes yard -high to giants of to up selling Fairbanks clothes in eparo time. The work ie easy. No high-pressure thirty feet or more. They paid no heed to amesmang u full timenowt and makeicee $100 a us, and after a time their numbers lessened, week. YOU CAN tool" SALESMEN WANTED! thinned down to widely separate groups, to We prefer full-time, experienced tai- stragglers ; then ceased. The hall was empty. loring salesmen, of course. But you can start on part time and what you As far as the eye could reach the columned don't know we'll teach you. We are spaces stretched. established 40 years and are one of the largest concerns in the field. We "Follow the crowd !" said Drake. "Do offer real $35.00 all -wool suits and overcoats, tailored to Individual you feel just full of pep and ginger, by the measure for only $03.75. BIG COM- way ?" MISSIONS, paid daily. Sample out- flt, salesm anshlp training, advertising I am aware of the most extraordinary, helps. all furniabed free. Write today, tell- ue all about your pant ex ieece- oar vigor," I answered. ing -present occupation. Fell detailsolont ageoffer will he cent to you -Free. "Look here, Dr. Thornton," he suddenly Fairbanks Tailoring Co., Dent.328 said. "What do you make of this?" Wabans,a Ave. at Oakley Blvd., Chicago

Play t he MFR E ni , HE Exposés HAWAIIAN SGUWAIANut;e C a[sè' of Scientific Swindles GUITAR i and t 1625 Only 4Motions toed la Just as the is instrument. ursnative'g appear often in Natives Do Hawaiian Instructors _ teach Y to master them quickly. Pictures -(1 -le/.- r SCIENCE AND INVENTION ebow how. Everything ea- I !% Ptalnad dearly. Play M Half Hour Easy Lessons I t`. If you know of some hocus-pocus scheme After you get the four Even if you don't know any motions you play a note from other. being used to swindle the public-write harmoniousewer you one printed icturesiions very little practice. No and the clear pictures the Editor about it. to learn quicklyke easy I edgee necessary. quickly.tPa scupley - Free Guitar Write at Once and Outfit In Genuine Beat Grain You'll never be lonesome with WANTED MEN Fabrikoid Case as soon as you en- this beautiful Hawaiian Guitar. To Make Metal Toys and Novelties roll. everything WriteApfor Special roes otcard wiilerll da. ACTnd I followed his pointing finger, and then A NEW BUSINESS In America No delnÿ, offers you great chance for Big OTHER Tenor Banjo, Violin, Tiple, Tenor Gaiter, Ukulele, looked at him inquiringly. Profits. As our Representative COURSES Banjo Ukulele-under w 11 -known iostruetora. you will do Big Business making FIRST HAWAIIAN CONSERVATORY of MUSIC, Inc. "The eyes !" he said impatiently. "Don't Toys, Novelties, 5 and 10e Store 9th FI 1$0 New N. Y. you see them? The eyes in the column!" Specialties, Auto Radiator Orna- Approved rivrtha Corresgemicnee Under Loua ments, etc. We co-operate In sell- of the State of New York I I looked again. The pillar was a pale ing goods you make, also buy them from you. An metallic blue, in color a trifle opportunity of a lifetime for the right man to connect darker than with a firm of many years' standing. Small Investment the Metal Folk. All within it were the puts you on road to success. WE FURNISH COM- PLETE OUTFITS AND START YOU IN WELL - myriads of tiny crystalline points. But they PAYING BUSINESS. NO experience necessary. ACT were dull and lifeless. I touched the col- QUICKLY if you want to handle Big 1928 Wholesale ClearedPIMPL in 24 hours. To prove Business and orders now being placed. Write AT Up-often umn. It was smooth, cool-with none of ONCE for free catalog and information. you can be rid of Pimples, Blackheads, Acne METAL CAST PRODUCTS CO. that subtle, warm vitality that pulsed through Dept. E, 1696 Boston Road New York Eruptions on the face or body, Barbers' Itch, all the Metal People with which I had come Eczema, Enlarged Pores, Oily or Shiny Skin, simply send me your name and address today-no cost- in contact. I shook my head. no obligation. CLEAR -TONE tried and tested in over "No," I said. "There is a resemblance. 100,000 eases-used like toilet water-is simply magical in prompt results. You can repay the favor by telling But there is no force about this-stuff ; no your friends; if not, the loss is mine. WRITE TODAY. life." ACCOUNTING E. S. GIVENS, 468 Chemical Bldg., Kansas City. Mo. "There might he -dormant," he suggested. á WT THOUSANDS of ambitions men HOW TO OBTAIN "It's sheer impossibility !" I exclaimed. á }lOwt0 are earning more money today and wondered at my own vehemence of Team because they know Accounting. A Perfect Looking Nose denial. ACCOu nlrng Send for our 80 -page book, "How My latest improved Model 25 corrects to Learn Accounting," and the now ill -shaped noses quickly, pain- "Maybe," he shook his head doubtfully. first lesson. Both will beeentfree. lessly, permanently and comfortably at home. It is the only noseshaping ap- "Maybe-but-well-let's be on our way." pliance of precise adjustment and a At each pillar Drake hesitated, scanning International Accountants Society, Inc. safe and guaranteed patent device that it closely with troubled eyes. But I, having A Division of the will actually give you a perfect looking Arm ER BeirruroN Iresmnu'rg nose. Write for free booklet which tells determinedly dismissed the idea, more you how to obtain a perfect looking was Dept.27 3411 So. Miehigan Ave., Chicago, ta. nose. N. Trusty, Pioneer Noseshaping interested in the lights that flooded this col- Specialist, Dept. 3014, Binghamton,N.Y, umned hall with their buttercup radiance. LEARN WATCH REPAIRING They were motionless and unwinking; not POPULAR ['_7 POPULAR CHEMISTRY You can learn by our modern and orig- discs, I could see now, but globes. Great lJ CHHEMISTRY inal system of Instruction every part of A Monthly Chemical Magazine the Watch Repairing Trade at home and small they floated, their rays extending Latest chemical news, experiments, for. as good or better than at a shop. You rigidly, and as still as the orbs that shed mulas, recent advancements in medicine, can earn money while learning and se- and other in features. Three cure a well paying pos.tion or start in them. Yet rigid as they were, there was trial coptes, 30 cents no stamps, please). business after completing our course of nothing about either ray or orbs sug- One year for $1.00. Book catalog free Instruction. Good watch repairers are that to yearly subscribers. always in demand and earn from $50 to gested either hardness or metallic. For particulars apply to the They $75 per week. were vaporous, soft as the witch lights that POPULAR CHEMISTRY CO. THE MILWAUKEE SCHOOL OF WATCH REPAIRING N. J. 166 Mason Street Milwaukee, Wis. cling at times to the spars of ships, weird Dept. MB Swedeaboro, gleaming visitors from the invisible ocean of atmospheric electricity. BE AN OIL EXPERT: BE A DETECTIVE When they disappeared, as they did fre- Trained men needed! Geologists, Drillers, Refiners or travel Make secret in (Chemists and Still Men), Oil Salesmen, earn 2 to 10 times Earn Big Money. Work home quently, it was instantaneously, with a dis- more than In other fields. Write today, FREE Booklet! veatlgat)ons. Experience unnecessary. Write Dept. S. A. Petroleum Engineering University, Dept. 263, Fort American Detective System, 2190 Broadway, N. Y. concerting sleight-of-hand finality. When Wayne, Ind. Science and Invention for March, 1928 1047

they did vanish, immediately, close to where they had been, other orbs swam forth with Earn Money the same abruptness, sometimes only one, larger it might be than that which had gone, sometimes a cluster of smaller globes, their Experimenting rays crossing each other. What could they be, I wondered-how The Skinderviken Transmit- light? ter unit is a marvel of En- fixed, and what the source of their gineering design-a practical Could they be the products of electro -mag- miniature transmitter, used netic currents and born of the interpenetra- by thousands of radio fans tion of such streams of force flowing above and experimenters for am- us? Such a theory might account for their plification purposes. disappearance, and reappearance-shiftings It is a most novel unit, of the flows that changed the light produc- having hundreds of uses. ing points of contact. Wireless lights? If so, here was an idea that human science this Thawing might elaborate if ever we returned to- WE PAY $5.00 "Now which way ?" Drake broke in upon Test your Ability my thoughts. The hall was ended. We stood IN CASH before a blank wall which disappeared into If you like to draw, let your talent the mists hiding the roof of the chamber. make your fortune. Opportunities in for every new use developed for this unit this field have and accepted and published by us. If you "I thought we had been going along the never been better. Pub- way-They-went," I said in amazement. lishers buy millions of dollars worth know anything about electricity or radio of here is a chance to make some money while "So did I. We must have circled. They illustrations every year. Complete you are having real fun. never went through that wall unless-un- the above drawing. Send it to us for less-" He hesitated. criticism. A FEW USES FOR THESE UNITS "Unless what?" I asked sharply. Many Artists Earn $500.00 a Month 1.` "Unless it opened and let them through," -LOUD SPEAKER ei...oti+ those great Increased advertising campaigns in RETRANSNI$SION- ///"o" "« he said. "Have you forgotten ovals-like cat's eyes that opened in the outer magazines and newspapers have iU - swelled the demand for artists. Many - walls ?" a I had forgotten. I looked again at the beginners triple their salary after wall. Certainly it was smooth and lineless. comparatively short time of Federal It was an unbroken, shining surface, a façade Training. J. F. Clymer writes us that I of polished metal. Within it, the deep set he received $50.00 for one drawing. SUTTON Art Nelson is now making $75.00 a C 11 points of light were duller even than they indeed, in- week. Herschai Logan says that he : had been in the pillars, almost, _11ir" distinguishable. has doubled his salary. The Federal Course includes illus- 111111g'illi mAPN o1'¡' "Go on to the left," I said, none too G[C(rv(n notion out trating, cartooning, lettering, poster I Y7 '02ºcLAnt "j=2" patiently.. "And get that absurd GRD LEN_ AMPLItIER of your head." designing, window card illustrating, "All right," he flushed. "But you don't etc. It's easy to learn the "Federal E -RADIO AMPLIFIER- think I'm afraid, do you?" Way." Instructions in each subject "If what you're thinking were true, you'd are written by a specialist in his art. have a right to be," I replied tartly. `And No other school can offer a course so .,.. to you I'd be afraid. Damned complete, by such famous authors. , I want tell Clare Briggs, Norman Rockwell, .ONE STAGE ....- afraid!" In my own perturbation I let slip AMPLIFICATION Neysa McMein, Sid Smith, Fontaine ,OAMy from me an unaccustomed adverb of pro- --. fanity. Fox and over fifty others contribute . For perhaps two hundred paces we skirted exclusive lessons and drawings espe- ñ v .a. r. the base of the wall. We came to an open- cially for the Federal Course. ing, a wide and high oblong passageway. The high quality work Federal -- graduates do, keep them in constant w,TpN. ::3 At its entrance the mellow, saffron light was SUTTON1....1, cut off as though by an invisible screen. The demand by leading publishers and organizations. Get in line s.. .W ,O4oáiNn . _ tunnel itself was filled with a dim, grayish commercial -TALMING LIGNT _DETECTOR - blue luster. For an instant I hesitated. today with other successful students. -CODE PRACTICING DEVICE- u. w+' "I wouldn't care to be caught in there by .In NK ' A Road To Bigger Things i ,ÿt Some «GI... .. any rush," I said. . .. is the title of our illustrated booklet, ,,....N.., "There's not much good in thinking of il which we will give free to every one .o.l, that now," said Drake, earnestly. "A few who sends in a drawing for criticism. 1 l ; .o. chances more or less in a place of this kind ; It tells about illustrating as a pro- ...'.. is nothing between friends, Dr. Thornton, <_- 4.,....w"" lm fession and shows the work of artists ' °' .'" eALowiN PHONE AMPLIrICR- take it from me. Come on." and students. TEST YOUR ABIL- We entered. Walls, floor and roof were ITY. Complete the drawing above in 12 Page Instruction Booklet composed of the same substance as the great pen or pencil. Fill out the coupon pillars and the wall of the outer chamber. below and mail it with With Each Unit They were filled like them with the dimmed your drawing. Get this With each unit is mailed a twelve -page replicas of the twinkling eye points. free criticism, TO- instruction booklet, containing suggestions "Odd that all the places in here are DAY. square," muttered Drake. "They don't seem and diagrams for innumerable uses. rI to have used any spherical or pyramidal ideas in their building-if it is building." t SEND NO MONEY Now that he had called my attention to ririPr`s s Order as many as you want-use the coupon it, I recollected that so far in the archi- t4,v-r;. fh below. When the postman delivers your tecture I had seen neither curve nor tri- order you merely pay him 95c plus a few angle. All was mathematically straight up S cents postage. If you order two units you and down and across. It was strange-still pay him only $1.75 plus postage. we had seen little as yet. of Illustratinel There was a warmth about this passage- PRESS GUILD, INC. S-3-28 way we trod, a difference in the air. The FEDERAL SCHOOL OF ILLUSTRATING, 16 -18-S -East 30th St., New York, N. Y. warmth grew, a dry heat, stimulative rather 3338 Federal School Bldg., Minneapolis, Minn. than oppressive. I touched the walls. The Please mail me at once Skinclerviken Trans- Please send your free book, "A Road to Bigger mitter Units, for which I will pay the postman warmth did not come from them. As we Things," together with criticism on my drawing. 05c., plus postage, or $1.75, plus postage, if I order went on the heat increased. two units. The passageway turned at a right angle, Name Aze continuing in a corridor half its former di- Naine mensions. Far away shone a high bar of Occupation pale yellow radiance, rising like a pillar of Addresa light from floor to roof. Toward it, per- Address force, we trudged. Its brilliancy grew. A City State few paces away from it, we stopped. The yellow luminescence streamed through a wide 1048 Science and Invention for March, 1928

slit in the wall. We were in a cul-de-sac- for the opening was not wide enough for either Drake or me to push through. The curious heat enveloping us came with the light through the slit. We peered through. At first all that I could see was a space filled with saffron radiance. Then this was splashed with tiny flashes of the jewel fires, little lances and javelin thrusts of burning emeralds and rubies, darting gem -hard flames rose -scarlet and pale sapphire, quick flares of violet. NORHALA APPEARS UNEXPECTEDLY Through the irised, crocus mist swam the The Story of radiant body of Norhala! "Dont tell me She stood, clothed only in veils of hair you never had a chance! that glowed like spun silk of molten copper, Chemistry her eyes wide and smiling, and ago you and worked at the strange DARROW "Four years I galaxies of tiny stars sparkling through their FLOYD L. same bench. I realized that to get ahead I gray depths. And all about her swirled a needed special training, and decided to let countless host of the Little Things. within your grasp! the International Correspondence Schools From them came the gem fire piercing the help me. I wanted you to do the same, aureate mists. They played about her in but you said, `Aw, forget it!' You had the scores of swiftly forming, swiftly changing, same chance I had, but you turned it down. goblin shapes. They circled her feet in shin- -interesting- No, Jim, you can't expect more money until ing, elfin rings; then opening into flaming discs and stars, shot up and spun about the Chemistry-Floyd L. -/Darrow you've trained yourself to handle bigger has presented this subject in a work." white miracle of her body in girdles of multi- colored living fires. Mingled with discs and concise, simple manner. There are lots of "Jims" in the world- stars were tiny crosses, gleaming with sul- Though a great deal of time in stores, factories, offices, everywhere. Are len, deep crimsons and smoky orange. and work was consumed in you one of them? Wake up! Every time A flash of blue fire, and a slender pillared research and study, the book a is in a readily grasped form, I. C. S. coupon your shape leaped from the floor. It became you see an chance is toward and it will be nothing at all staring you in the face. Don't turn it down. coronet, a whirling, flashing halo which streamed up the flaming tendrillings for you to obtain a good un- Right now over 180,000 men and women of Norhala's tresses. derstanding of the subject. are preparing themselves for bigger jobs Other halos circled her arms and breasts. 530 PAGES-b" x 9" and better pay through I. C. S. courses. They spun like bracelets about the out- The book is beautifully and You can join them and get in line for stretched arms. sturdily bound, with a good promotion. Mark and mail this coupon, Then like a swiftly rushing wave a host supply of interesting illus- and find out how. of the Little Things thrust themselves up, trations. her and hid her in a jewelled cloud. covered The price is a low figure at . itself from INTERNATIONAL CORRESPONDENCE SCHOOLS I saw an exquisite arm thrust gain such a complete "The Universal University" their clinging. I saw her head emerge from which to Box 622IE, Scranton, Penna. education as it affords Without cost or obligation, please send me a copy of the incredible draperies of living jewels. I your booklet, "Who Wins and Why," and full particulars heard her laughter, sweet and golden and far about the subject before which I hare marked X: The Story of Chemistry Industrial Management Business Correspondence away. Personnel Management Show Card and Sign Madonna of a Metal People! Traffic Management Lettering Accounting and C.P.A. ['Stenography and Typing "Their babies !" I whispered. Special Price Coaching Civil Service "Their nursery," sighed Drake. "The el Cost Accounting Railway Mail Clerk $3.98 Bookkeeping D Common School Subjects nursery of the-Little Things !" D Salesmanship High School Subjects Secretarial Work Magazine and Book Norhala was gone, blotted out from our USE COUPON BELOW Spanish D French Illustrator sight. Gone too were bar of light and the Advertising Cartooning been peering. TECHNICAL AND INDUSTRIAL COURSES chamber into which we had Electrical Engineer Architect We stared at a smooth, blank wall. With Electric Lighting Architects' Blueprints swiftness the wall had closed, Mechanical Engineer Contractor and Builder ensorcelled THE STORY Mechanical Draftsman Architectural Draftsman even as we had stared through it; closed so Machine Shop Practice Concrete Builder Railroad Positions Structural Engineer quickly that we had not seen its motion. Gas Engine Operating Chemistry Pharmacy U Civil Engineer Automobile Work But the opposite wall was opening ! s, J Surveying and Mapping D Airplane Engines a.aa,9.,. . _ Metallurgy :limning Agriculture and Poultry First it was only a crack, then rapidly it Steam Engineering Radio D Mathematics widened. I gripped Drake and shrank with him into the farthest corner. There stretched a loxi .L. I Name pP

Yrain at ome to Flying Blind Orders - Inquiries (Continued franc paye 1037) Can be e Gi'. ',act". PE mired;; ing in element the body of man. Captain id 0 Ocker, who entered the Army through the by Cavalry in 1898 and who began flying in MILL , Arine!'af' 1912 with the original Curtiss school, later Tr-Le Do you want a better position and a higher salary? You can becoming one of the original four Army have these if you can do the work. LaSalle experte will show air instructors, has now proven, with the you how, guide you step by step to success and help solve your personal business problems through the time -saving collaboration of Surgeon D. A. Myers, after . LaSalle Problem Method. Our salary -increasing plan enables you to prepare during your spare hours. without inter- seven years of experiment, that the vestibular ference with your present duties. Simply mark on the coupon canals, far from balancing the body in them- the field in which you desire success, and we will mail you a POLK' PREFERENCE BOOK valuable book describing the opportunities in that field, to- selves, contribute delusions in the air which gether with an outline of our salary -increasing plan. Also lead directly to pilots and Mailing List Catalog copy of "Ten Years' Promotion in One." There is no cost or spinning and diving obligation. Find out how the salary -increasing plan starts into the ground, while they confidently be- Gives counts and prices on over 8,000 average men and women on the high road to success and different lines of business. No matter financial independence. Check and mail the coupon NOW. lieve they are on safe courses. what your business, in this book you -Find Yourself Through LaSalle Many pilots who have been observed by will find the number of your prospec- - - tive customers listed. LA SALLE EXTENSION UNIVERSITY comrades to come suddenly out of clouds Valuable information is also given as to The World's Largest Business Training Institution spinning and continuing their spin on into how you can use the mails to secure Dept, 3384-R Chicago orders and Inquiries for your products Tell me about your salary- increasing plan the ground below, have flied through this or services. for my advancement in the business field misguidance of the semi -circular canals. Un- checked. Send also copy of "Ten Years' Write for Your FREE Copy Promotion in One," all without obligation. til now, it has been believed they permitted R. L. POLK & CO., Detroit, Mich. Business Management Person- their planes to get out of control, which was Largest City Directory Modern Salesmanship nelMan- Publishers In the World agement not the case in most instances. Had a Mailing List Compilers-Business Statistics Higher Accountancy Producers Direct Mail Advertising Traffic Management Expert brother pilot been sitting beside them, they of Railway Station Book- would doubtless have insisted they were fly- Management. keeping Law -Degree of LL.B. Business English ing safely and on a proper course. Commercial Law Commercial Spanish Industrial Management Effective Speaking C. P. A. Coaching WHY PACIFIC OCEAN FLYERS WERE LOST Banking and Finance Stenotypy Help Wanted O Modern Business Corre- ID Telegraphy When the writer was first called into con- spondence Credit and Collection We require the services of an ambitious person to Modern Foremanship Correspondence sultation with Captain Ocker and Myers, it do some special advertising work right in your was by a telephone message, which stated own locality. 'The work is pleasant and dignified. Name Pay is exceptionally larga No previous experience that the officers were certain they could ex- is required, as all that is necessary is a willing - Present Position plain the loss new on your part to carry out our instructions. of most of the trans -oceanic If you are at present employed, we can use your Address planes which failed to arrive at their over- spare time in a way that will not interfere Witt. your present employment-yet pay you well for seas destinations during the tragic circus of your tima death which prevailed during a few months If you are making less than $150 a month the 1927, offer I am going to make will appeal to you. 'Your of following the momentous flight of spare time will pay you well-your full time will Colonel Lindbergh from New York to bring you in a handsome income. Paris. Its costa nothing to investigate. Write me today All available statistics tended to prove that and I will send you full particulars by return so many mail and place before you the facts eo that you Wright Whirlwind engines could can decide for not conceivably have yourself. failed in flight. The ALBERT MILLS. Ben. Mgr. Employment Dept testimony of the few successful overseas 200 American Bldg., CINCINNATI, OHIO. flights showed that all the successful pilots 500 TRICKS-IOC. suffered a number of spins and death -cheat- BE POPULAR-LEARN TO ENTERTAIN ing moments; and Amaze and mystify your friends. Earn Money further, that those who ar- SAW and 7 at Clubs and Parties. It's easy. No skill rived at their destinations all utilized some required. Our copyrighted book, "Fun- BLADES SI Magic-Mystery" tells how and explains variation of the Ocher -Myers system. Pilot many Tricks you can do. Also catalogs over Ernest Smith, the first civilian pilot fly Cuts Wood & Iron 500 Mystifying Tricks-Illusions-Jolies- to Puzzles-Books-European Novelties, at Re- the Pacific between San Francisco and duced Prices. New 1928 Edition, profusely Hawaii, personally Illustrated, sent postpaid, only 10e. attended the Ocker -Myers instructions and after his flight to Hawaii The F.P.M. saw cuts wood, iron and bakelite LYLE DOUGLAS, Station DALLAS, A-3, TEX.. declared that his success was entirely due to! at any angle. Used and recommended by ex- the perts in every line. Unequalled for sturdy, PROMPT SERVICE -o -LOW PRICES prevention of vertigo by their method: lasting construction and fine workmanship. He spun twice in the first 600 voiles out, L'lades of finest tempered steel. Get the each time coming out successfully by the use F.P.M. Saw at any hardware store or order of his instruments. direct. ea ambi nrd ed time. Lieutenants Maitland and Hegenberger, 1 F.P.M. Saw and 7 Blades sent prepaid $1.00 Electrical Over 5000 21men trained. Condensed course in Theoretical and Practical Elec. who were also using the system, then issued DEALERS Write for Discounts JOBBERS trial Including the statement to the close- Captain Ocker that the N.AAshland Ave. Engineerin ly related Army's success was due to the quelling of F. P. MAXSON,3722 Chicago subjects of Mathematic' and Mechanical Mahler. Studente construct motors, Install wiring, teat elec- vertigo by psychological cooperation with trical machinery. Course designed to be comDleted the instruments. In one college yen', BLISS, HOW COL. LINDBERGH FLIES ELECTRICAL SCHOOL fer'yeur profession In -the Following these remarkable statements, it In Amazing Method -- east interesting city the world. was ascertained Irregularpe made Catalog on request. that Colonel Lindbergh, be- without rtIPreparo63 Tektites Ave.. WuMneten,- fore leaving Diego, his at on. Results cuar- O. San where plane was anteed.Quick and per- constructed, had had a lengthy motion m. Is absolutely pic- D.ainleao.harmleae.Uver ture made of the of his instruments 60000 doctors and users working praise it as a most mare l- while in the air in the factory test flights. oue method. These were made by Major H. A. Erickson, Thirty Day Free Trial Rash roar name and ad- Army Photographic Officer at San Diego, dress today for Free Plan. Easy to learn watch and and they were then run off privately for ANITA INSTITUTE clock repairing, engraving, 373 Anita Building. and jewelry work by our Lindbergh, while lie studied every action of Newark, N. J. practical system of individ- the instruments for several days. Then, ual training. Day or evening he school. Learn in a few months working alone, adopted the identical to fill job paying up to $100 a Ocker -Myers system without realizing the Week or start your own business. Big shortage of trained watchmakers. We help you earn biological reasons therefor, but wise enough FOREST RANGERS money while you learn. Write at once for FREE BOOK! to understand that he liad better depend on MEN, get Forest Ranger job; $125-$200 mo. and NATIONAL SCHOOL OF WATCHMAKING home furnished; hunt, fish, trap, etc. For details 4340 South Michigan Avenue Dept.30 Chicago, ill. instrumental flight, though he was credited. write Norton, 2650 Temple Court, Denver, Colo. with rare flight sense. And the newspapers TAUGHT AT HOME. called that man "Lucky Lindbergh." If it be Write today for FREE SQUAB g) BOOK C9 FREE Book. IT TELLS How luck to discover through the channels of Breed squabs and make money. Sold by millions. to Learn to Play. Your common-sense a principle worked ont by a Write at once for free 40 -page book beautifully onlyTENORBANJO expense about 2c Per Day for music and postage used. printed in colors telling how to do it. You flying officer of 15 years' experience, asso- will be surprised. PLTMOUT11 ROCK SOUKS CO. AMERICAN SCHOOL OF MUSIC H 64 Manhattan Building Chicago, Ill. ciated with one of the leading flight surgeons 506 St., Melrose Highlands, Mass. 1051 Science and Invention for March, 1928

of the world in collaboration, then indeed was Colonel Lindbergh lucky. But the ap- I'll Give You pellation appears very paltry after studying the young Colonel's elaborate preparation for his feat. BULLDOG COURAGE SECOND TAIL SPIN OFTEN A DELUSION Captain Ocker states that, when the "City In 48 Hours of Dallas" plane, piloted by Captain Erwin, itself first in one spin and then in a -OR NO COST ! reported second one, after which the plane was Are you timid? Bashful? Self- definitely lost, it had no actual second spin conscious? Are you afraid of people?-afraid of superiors? and that the personnel of the plane, with Give me 48 hours and I'll lights extinguished make you bristle with bull- their instrument -hoard dog courage-or no cost! and flying blind, were under a common de- Thousands of men and wo- lusion regarding the second spin. The sec- men are being held back- ond, or "hallucination" spin could have been made miserable-made un - sys- DAVID V. B SH because compensated for with the Ocker -Myers happy. Why? Simply it. Un- of bashfulness-self-consciousness, fear of criticism, tem. But they knew nothing of business worries and dozens of other fears. doubtedly, states Captain Ocker, the second Yet fear is ABSOLUTELY UN NECESSARY. spin was a delusion, and the pilot, when he I have discovered an amazing meth od which ban- ishes fear forever! No trouble! No inconvenience. worked the controls to get out of it, was' No long waiting for results. My method is perfectly himself and companion to logical. It works simply driving simple-perfectly natural perfectly in almost instantly. Try it. You will be astonished! In death the Pacific Ocean. just a few hours you will find yourself brimming over It might be mentioned here that Ocker with splendid new courage-new daring-new self- knows his planes. And all their conceivable confidence. reactions. As one of the Army's first two ONLY SO CENTS (now Dr. Bush gives you his secrets of real, he-man courage acrobatic pilots, he, with Lieutenant in his book called "Spunk: It is one of the most startling Major) B. Q. Jones, developed all or most books ever written. You can't read it without a quick- EARLE E. LIEDERMAN-"The Muscle Builder" ening of your pulse-without a surge of red-blooded of the early acrobatics and special flights Author of "Muscle Building," "Science of Wres- courage. when the Army possessed only two planes tling," "Secrets of Strength," "Here's Health," This book is declared to be the masterpiece of Dr. etc. Bush, who has astounded throngs in America's greatest housed in crude hangars at Rockwell Field, "Endurance," cities and shown thousands the one way to health, prosperity, and self-confidence. Write for this amazing near San Diego, California. book today. Send only 50 cents in full payment. If you The work of Captain Ocker has been the HowStrongAreYou? are not delighted, return the book within 5 days and your money will be Instantly refunded. development of a device incorporating a Can You Do These Things? V. BUSH, Publisher indicator and a standard with one arm; bend DAVID Ill. bank- and turn- Lift 200 lbs. or more overhead Dept. K1093, 225 N. Michigan Blvd., Chicago, be added to the Jones- and break a horseshoe; tear two decks:of playing magnetic compass to yourself with one hand. Barany flight -testing chair in the surgeons' cards; bend spikes; chin offices, so that pilots can be instructed at the you do any of them? I can and many of my 120 MILES ON 2 CANpupils can. It is remarkable the things a man very beginning how their vestibular canals really can do if he will make up his mind to be strong. GALS. OF GAS in the inner ear delude them in the air. This I have taken men who were ridiculed because of¡their Starts Coldest Motor Instantly. much has been done and the device has been frail make-up and developed them into the strongest men of their locality. For all cars, including the NEW FORD. One Free presented to the Chief of Air Corps and the 90 Days drawing account and of Surgeons. Captain Myers I Want You for to Exclusive Agents. Liberal Chief Flight These are the days that call for speed. In olden days traveling expenses guaranteed to distributors. has developed the biological reactions of the it took years to develop a strong, healthy body. I can QUICKSTART CO. method, and the foremost instrument makers completely transform you in 90 days. Yes, make a CURTAN- in with the Air Corps arc complete change in your entire physical make-up. Dept. 863-C, 154 E. Erie Street, Chicago, III. now collaboration In 30 daysI guarantee to increase your biceps one full looked to for the mechanical equipment of inch. I also guarantee to increase your chest two inches. the planes. But I don't quit there. I don't stop till you're a finished reports and dupli- athlete-a real strong man. I will broaden your S4 9s Prior to transmitting shoulders, deepen your chest, strengthen your neck. A SHIP MODEL FOR cates of the test devices to the Chief of I will give you the arms and legs of a Hercules. I will the Major Gerald C. Brant, put an armor plate of muscle over your entire body. Flight Surgeons, powerful lungs which S ta Maria r the Mayflowerr hh Field, Presidio of Sall But with it come the strong, ownnoreplica hands. We will furnish the parts commanding Crissy enrich the blood, putting new life into your entire being. complete for only $4.98 plus a few cents Francisco, and the superior commanding of- you will be bubbling over with strength, pep and for postage. No tools needed except a vitality. small hammer. Write for our Illustrated ficer of Captains Ocker and Myers, issued catalog. that no pilots of the Air Corps A Doctor Who Takes His Own MINIATURE SHIP MODELS instructions 3518-20-22-24 Baring St. should be perntitted to fly Army air craft, Medicine Dept. S-6 Philadelphia, Pa. unless they had been instructed in the Ocker - Many say that any form of exercise is good, but this understood it. is not true. I have seen men working in the factories, Single Acting High Speed Myers system and and mills who literally killed themselves with exercise. They ruined their hearts or other vital organs, ruptured Model Steam Engine THE NEW PILOT TEST -CHAIR themselves or killed off what little vitality they pos- bore sessed. Type Q Stationary -1 in. in ...s,4.4of health and x fl 13l in, stroke. Weight, 8 By attaching the bank -and -turn indicator I was a frail weakling myself search lbs. 6 ozs. Price complete, chair, strength. I spent years in study and research, analyzing $17.00, forwarded prepaid. Many and a compass to the Jones-Barany my own defects to find what I needed. After many other types model Engines, on the results were illuminating. Men who tests and experiments, I discovered a secret of pro- Boilers, Boner Fittings. Catalogue 20e. (refunded own arme over six first order).! vomited and who suffered various phenomena gressive exercising. I increased my found and a half inches, my neck three inches and other parts Bathe Mfg. Co., Dept. 2-5214 Woodland Ave.. Phila., Pa. of vertigo, without the instruments, of my body in proportion. I decided to become a public themselves at all times perfectly orientated benefactor and impart this knowledge to others. and without nausea, when the instruments Physicians and the highest authorities on physical culture have tested my system and pronounced it to were added for their undivided attention. be the surest means of acquiring perfect manhood. LESSONS This was achieved by mounting a case con- Do you crave a strong, well-proportioned body and the taining the instruments on the chair and abundance of health that goes with it? Are you true ¿VCARTOONON APPROVAL to yourself? If so, spend a pleasant half-hour in learn- course i. cartooning on apMoeaL causing the pilot to look upon them in such it. The knowledge is yours for the . Gm ei 20 lemon ing how to attain my personal instructions d then pny . sway under see nothing but the asking. Mw I,, Iran a manner that he could weekly while learning. Only a WEE[í Send for My New 64 -page Book No valeta in it.. 5 week: timer an make money. instruments and no extraneous objects n ° n.cewary. Send 5c samp, for aienê - TO simulating flight in clouds or "MUSCULAR DEVELOPMENT" the room, thus Send One Penny- PAY fog, or at night when earthly and heavenly IT IS FREE-Don't invisible. The It contains forty-eight full -page photographs of my- objects were beclouded and self and some of the many prize-winning pupils I have photos and drawings show this new pilot trained. Some of these came to me as pitiful weaklings. AT HOME help them. Look them over and LEARN AVIATION Hinton test -chair. imploring me to Under Lieut. Walter to marvel. This book will prove a real inspiration to AVIATION INSTITUTE OF U. S. A. Captain Ocker does not limit himself you. For the sake of your future health and happiness Dept. A-33, 1115 Connecticut Ave. N.W., Washington, D.C. the apparatus disclosed in the accompanying do not put it off. Send today-right now before you drawings and description, as the method and turn this page. apparatus may be varied and improved, as EARLE E. LIEDERMAN the need arises, without departing from the Dept 2703 305 Broadway New York City of his developments. Send 51.00 for Beginners' Instructions with spirit EARLE E. LIEDERMAN, laugh producing program of 23 conic trick The whole invention relates to a principle Dept.2703, 305 Broadway, New York City of Chalk Talk supplies free. Dear Sir:-Please send me absolutely FREE and with- drawings. Catalog Ocker in 1919, and of BALDA ART SERVICE. Dept. 4. Oshkosh, Wisconsin discovered by Captain out any obligation on my part whatever, a copy your perfected by November, 1926. latest book, 'Muscular Development." (Please write or definitely print plainly.) STROUT'S SPRING FARM CATALOG wherein are combined the Jones-Barany Just out; hundreds of bargains, Ilke 25 acres black loam, on turning chair, the orientator, the aeroplane, Name. stream near concrete hway & village; nice 5 room house & bldge Street. only $1100, Including horse, 4 cows, poultry, tools, crape; part or anything that turns with such instruments cash. Write today, copy free. hank-and -turn indicator, compass, City. State STROUT AGENCY, 255 Fourth Avenue, New York City as the 1052 Science and Invention for March, 1928

altimeter, inclinometer and air -speed indicator in a manner such as indicated, for the purpose of training and safeguarding pilots 250 POWER O while flying in darkness, fog, storm, or any MICROSCOPE .MAD[ 1N U.S.A. I combination of these weather conditions. The principle involved teaches the pilot Educational, entertaining, this that after one or more blind turns, he is fine microscope helps all to know suffering from a state of vertigo, which is life that can't be seen with un- per- aided eye. Tiny insects look like a reaction experienced by every normal monsters. Plant and mineral life son. The instruments mentioned are to be reveal new wonders in form used to correct this error of our senses, and and color. Used by stu- absolute reliance can be placed in them until dents, dentists, physicians, such state of vertigo has passed away. scientists-in home, office, The discovery also covers the use of the school, and laboratory. dis- Precise optical foot rudder in the training apparatus, to qualities. Build and Fly a 3 -Ft. Model of close amount of deviation from the true the Magnifies zoo to LINDBERGH'S course by the pilot when in a state of vertigo. 25o times. Tilting "Spirit of St. Louis" HALLUCINATIONS PILOTS_ HAVE stand, fine finish, TWO plush- Plans for This IDEAL New York Parts Mono nickel trim, Model Airplanes plane is a perfect copy, 3 ft. size, of In fog or blind flying, when the "feel" of lined case, prepared slide, 25c per set the machine in which Lindbergh cross- are two instructions. New York Paris ed the Atlantic Ocean. Any bright the airplane leaves the pilot, there At your dealer or Plane, FOKKER boy can build this model: The IDEAL distinct hallucinations that all normal pilots direct postpaid. North Pole Plane, Construction Outfit contains every- Money hack guar- CURTISS JN4D thing needed: all parts, fittings, mater- are subject to: First, when a pilot is turning 2 Biplane, DORA ials and supplies, including careful and then discontinues the turn and flies a antee.Othermodels VILAND Biplane, Instructions, plans and diagrams. The $2.50 to $S.jo. NC 4 Naval Sea model Is wonderful; has mane features straight course, his senses tell hint that he Catalog Free plane, Bleriot- of the original and Is guaranteed to is turning in the opposite direction; and, sec- "I aube or Nieuport fly. Complete Construction $7.50 monoplanes, Cecil Outfit P ond, when he is turning and simultaneously Wollensak Optical Company Peoll Racer. (West of Denver, Colo., and In 661 Hudson Avenue Rochester. New York Canada, price is $8.00) descending, upon straightening out and fly- HOW TO Ask your dealer or order direct. ing level, he will liare the sensation of turn- BUILD AND FLY New 64 -page Book ing in the opposite direction and ascending. MODEL AIRPLANES of Model Airplanes mast Teaches the principles of flying: contains plans and direction for building gliders TOP VIEW OF FLIGHT AOMes and racers, and full information about scale Models of real planes; also moat PILOT TURNING ANO THEN complete catalog of materials for STRAIGHTENING COURSE Aever for SC onaGailoi model builders. Sent postpaid '\ HAS FEELING THAT HE IS 57 Ideal Aeroplane & Supply Co., Inc. TURNING IN OPPOSITE F Spring St. New York City DIRECTION According to a recent article by the 165-169 ß president of the world's largest motor research corporation, there is enough energy in a gallon of gasoline If converted 100% In mechanical energy to run a four cylinder car 450 miles. Build Your Own FIRST HALLUCINATION NEW GAS SAVING ASTONISHES HORN PILOT SIMULTANEOUSLY TURNING INVENTION EXPONENTIAL ä`!S=1;& This marvelous 17x21" AND DESCENDING, UPON CAR OWNERS cabinet orthophonie STRAIGHTENING OUT ANO horn with a 96" air LEVEL, GETS THE A marvelous device, already installed column can be easily RFLYINGSENSATION OF TURN- on thousands of cars, has accomplished built in a short time by ING IN THEOPPO- O wonders in utilizing a portion of this any amateur. It Is built SITE DIRECTION waste energy, and is producing mileage or soft wood which pro- AND ASCENDING tests that seem unbelievable. Not duces the best tone only does it save gasoline, but it tivallty of' any known i also creates more power, gives instant material. starting, quick pick-up, and eliminates carbon. We furnish you with a set of SECOND HALLUCINATION FREE SAMPLE and $100 a Week FULL - SIZED To obtain national distribution quickly, men are being PATTERNS Illustrating the two major hallucinations that appointed everywhere to help supply the tremendous many demand. Free samples furnished to workers. Write which have been ac- affect the pilot of a plane under today to E. Oliver, Pres., for this free sample and big curately and scientific- conditions. money making offer. ally worked out according to the exponential WHIRLWIND MFG. CO. principle, and from which it is These reactions are not shown or explained 999-183E Third St., Milwaukee, Wisc. DECIDEDLY SIMPLE TO BUILD to the student or old pilot by the usual this latest and most efficient tone producer. It Is most any tests gratifying to build your own horn, especially since the Jones-Barany chair tests or other results are equal to those of the most elaborate and now in existence. Therefore, Captain Ocker's expensive horns on the market. invention is of the utmost importance, as it Send $2.00 for a set of these full-sized natterns and complete instructions, thoroughly demonstrates and explains these reactions to the pilot, thus teaching him to RADIO PRODUCER COMPANY not in his 1244-5 Jefferson Bldg. Dept. 7 Peoria, Ill. place his faith in instruments and senses. These principles have not only been tested in the chair, but also in the air by airplane, and have been found to be the same Be an electrical specialist. Gain quick success 'in this most in both places. fascinating and profitable field. Learn at National in the Duet cm tNs The magnetic compass is used to demon- center of tremendous electrical projects costing more than TURN YOUR TALENT INTO MONEY instrument causes con- $100,000,000.00-unlimited opportunities now. - Cartoonists earn from $50 to $250 per strate that this classic Practical, intensive training by National's job experience week-some even more. Remarkable new giving an illusion that Circle System of Drawing teaches you in fusion, by frequently method in 6 to 9 months. All technical essentials included. half the usual time. Send for booklet the machine is turning around the compass, School endorsed by leaders in electrical industry. You learn and sample lesson plate explaining full is turning, all branches of electricity; radio. Million dollar institution; details of the Course. No salesman will hereas the compass dial itself all modem equipment and training fad'. call. clue to forces caused by the rapid turning. ities. Life scholarship. No age limit. Free THE NATIONAL SCHOOL employment service. Over 17,000 success. OF CARTOONING "I he bank -and -turn indicator, therefore, is 628 Penton Building Cleveland, Ohio ful graduates. 23rd year. Big, illustrated used as a stabilizer for the magnetic compass. 84 -page catalog sent FREE. Write today. One of the objects of the device is to pro- »O vide means whereby a subject under exami- NATIONALALE r1 SSROoL nation for his physical qualifications for fly- Dept. 250 4006 So. Figueroa, LOS ANGELES, CALIF. ing duty, may be brought to a full realiza- tion of the inaccuracy of his physical and may oc- Wonderful, new device, guides your hand; corrects mental senses under conditions that Worn by praetical men everywhere. your writing in few days. Big improvement in three flight. Guaranteed shock proofme and weather hours, No failures. _Complete outline FREE. cur during o um dial. means Fine imported full jeweled movement. Rich Perfect Penmanship Inst., Dept. 44, St. Louis, Mo. Another object is to provide 'silver finish. Genuine leather strap. Sold may be caused to ex- elgewhere for $10.00. Fully guaranteed whereby said subject to a you complete and entire satisfaction. sensations similar SEND NO MONEY: Pay to your postman for names of new custom- perience, on the ground, only $.99 plus the postage on delivery, r "'Zeach ers who wear an artificial eye. to those which he would experience during JENKINS CORPORATION Send names of any you know and earn flight in an airplane, when said airplane be- 621 Broadway, New York, Dept. 6SFR commission. Nothing to buy or sell. came uncontrollable due to a loss of speed, DENVER OPTIC CO., 795 Quincy, Denver, Col. or loss of ground or horizon visibility. MEN TO LEARN It is intended to demonstrate to each pilot MOTION PICTURE OPERATING A big money profession-$2,000 to $4,000 Insure your copy reaching you each month. Sub- now in service, both Government and commer- scribe to SCIENCE AND INVENTION-$2.50 the de- MOVIE OPERATORS SCHOOL Inc., 230 cial, as well as to all pilot-aspirants a year. Experimenter Publishing Co., in - 61 SPROAT ST. DETROIT, MICHIGAN Fifth Avenue, New York City. ceit which is practiced upon man by the 1053 Science and Invention for March, 1928

ner ear, when it is depended upon for flying equilibrium in blind flight. A very practical demonstration was given recently when a pilot attempted desperately to make a landing on what appeared to him to be a fairly good field. He had just come out of the fog and the ground was only faint below him. Try as he would, he could not land, but he felt a great pull behind him, as though some giant magnet were pulling his plane backwards to prevent his landing. He dived at his "landing" with great speed and tried to set the plane down, but every time as he slowed his motor, the plane began to Aviation slide backwards, and he had to put on full throttle in order to pull out. Furthermore, Brings Quick the ship labored heavily as he pulled up to avoid a crash. Before any disaster overtook him, he for- Success tunately discovered that he was in reality ARTHUR PRYOR no other flying up and parallel to the sides of a preci- TO young men of daring America's Greatest field of work offers such a fascina- Trombone Virtuoso. pice, with his nose pointed at the zenith and Director, Pryor's Band tion, such high pay, nor such oppor- his tail toward the ground. Had he cut his of have tunities for quick success as the field motor to make his landing" he would is practically the Holton Reve- backwards and died in the valley Aviation. As yet, aviation "With crashed in its infancy. But now is the time to writes below. Instrumental flying, rather than in- lation Trombone", stinct -flying would have prevented this ex- get in. Arthur Pryor, tithe seem- perience, which actually happened to one of Amazing Opportunities ing impossible is made the mail pilots of the earlier air -mail days. Today, the mail pilots are flying by instru- in Airplane Industries possible. I am positively ments. In the automobile industry and in the moving Under the Ocker -Myers instructional sys- picture business hundreds of men got rich by astounded." getting in at the start. They made their success tem, Air Mail Pilot J. L. Rutledge, of the before others woke up. Today, these lines offer Have you tried our new Pacific Air Transport Company, was the no greater opportunities than a hundred and one first man to land a plane entirely by instru- others. BUT AVIATION IS NEW. Get in while American Model that the opportunities are big. All over the country ment in a fog which extended from the there will be a clamor for trained men. It will not "tunes with a touch of ground to the 5,000 feet mark on the alti- be a question of pay but of getting capable men. the thumb"? Patented meter. The act is still a dangerous one, but with fog -flying safe aloft, landings in Become an Aviation Expert -- the world's quickest fog are now commanding the attention of The study of aviation is almost as fascinating as the actual work. Every lesson is full of in- tuning trombone. Captains Myers and Ocker. They promise terest. That is why it is easy to learn aviation. some developments in this field in the near You do not have to make yourself study-it is Write for folder, "The Trom- future. like reading an interesting book that tells you bone that Built a Factory." things you have always wanted to know. Only one hour each evening will give you the basic time. FRANC HOLTON & COMPANY training in a surprisingly short McNaughton, Chicago, says: 326. CHURGi Sr. ELKHORN, WIS. One student, S.F. "Your lessons are like is more, after one rewad- ing, the student gets a thorough understand- MODEL DEPARTMENT ing. One never tires of PICK reading them." James BLUEPRINTS JOB ! Powers, Pa., another YOUR student, says, "I am indeed surprised that Correct-Easy to Follow Flying such a valuable course Airplane Instructor can be had from such Airplane Engineer practical men for so 1-2 Horizontal Steam En- little cost." gine details set $1.00 Airplane Repairman Airplane Assembler 3-4 Boiler construction for Airplane Personal above set $1.00 Mechanician Instruction 5 880 Ton Bark 50c Airplane Inspector by Experienced Men JDon't Envy the Plumber` Airplane Builder Men who have had ac- 6-7 Twin Cylinder Steam Airplane tual experience give BE ONE Engine and Boiler. set $1.00 Salesman you personal attention,. $11.00-$16.00 PER DAY and work EVERY day, is Exhibition Manager They select the lessons tlhe Plumber's wage. 8-9 Gasoline Fired Loco- Airplane Contractor lectures, blueprints and Every skilled workman will tell you that Plumbers have motive set $2.00 bulletins. They tell you the best of lt. WINTER and SUMMER the Plumber Airplane Motor things that are essen- Is bust at top wages. No skilled Plumber is ever out 10-11 U. S. S. Constitution, Expert tial in everyday prac- of a jab-compare his opportunities with any trade, plus Airplane Designer the opportunities of having your own shop. "Old Ironsides" set $1.00 tice. Each lesson is We teach you Plumbing with TOOLS (not books) under easy to read and un- Licensed Master PLUMBERS in one of the finest 12 13th Century Man -of - derstand. equipped schools in America. We make you a Plumber, every branch is taught thoroughly-Lead Work-Blue War 50c Print for plan reading-all other tricks. set 50c Get Big FREE'Book-Now without 13-14 Chinese Junk TO 12 previous Send coupon below for New Book, just out, LEARN IN 8 WEEKS 15-16 Electrically d r i v en Opportunities is if you are making less than $60.00 a week you owe it in the Airplane Industry. It to yourself to investigate. Get FREE catalog that tells Automobile set $1.00 interesting and instructive. It will show you in pictures and words how we teach this trade. Special many things you never knew before about dates now - 17-18 How to Build a Re- aviation. We have but a limited supply of UNIVERSAL PLUMBING SCHOOL flecting Telescope .. $1.00 these books-send the coupon before they are 2057 Troost Ave. KANSAS CITY, MO. all gone. J 19 Roman Ballista 50c 20-21 Simple Steam Engine, American School of Aviation IS MISERY set 50c 3601 Michigan Ave., Dept. 1423 DEAFNESS 22 "Santa Maria," complete 50c Multitude; of persons with defecFiv'i hearing and Head Chicago, Ill. Noises enjoy conversation, go to Thea. - 23-24 Model U. S. S. Ports- treandChurch because they useLeonard mouth set $1.00 Invisible Antiseptic Ear Drums. Tiny Megaphones fitting in the Ear entirely 25 Building a Model Tug- American School of Aviation out of sight. No wires, batteriesor 50c 3601 Michigan Ave., Dept. 1423 bead piece. They are Unseen Corn. boat Chicago, Ill. forts and inexpensive. Write for booklet and swotnstatementofthe Send Orders to Without any obligation, send me your Free inventor who was himself deaf. Book, Opportunities in the Airplane Industry, 785 705th Ave., N. Y. also information about your course in R. 0. LEONARD, Inc., Suite MODEL DEPARTMENT Practical Aeronautics. SCIENCE AND INVENTION FEMALE 1 re. NOT spend Spring. Summe, Fall gather- i.,, r2 Name Wily.WERA]V!a arg butterflies, insects. I buy hundreds of kinds :' ` -.4, 230 Fifth Avenue far collection s Some .orti, SI to $7. Simple work with my Instra- - - - Street pricelist Send IOs NOT STAMPS] for my Prospectus New York City bens,pictures. Stau before sendis butterflies. Mr. Sinclair, Dealer in In City esetn, Dept. 41 Box 1424, San Diego, Calif. 1054 Science and Invention for March, 1928

How to Make a Barometer By RAYMOND B. WAILES (Continued froh page 1009) i

BANK $150 to $300 More Each Month Easily earned from HB 8 -Hour Battery Service - with practically NO INVESTMENT on your part Charging batteries in % the time required by other to make shops brings you the business. Costs less to operate, A sheet of paper is folded like this making you more net profit on each battery. Re- a funnel to filter and purify the mercury. quires no special experience and PAYS FOR ITSELF on easy monthly payments WITH A PROFIT BESIDES. into the side of the cork so that air may enter the bottle. Two wooden clamps or Costs Only $16 Monthly cleats must be added to help support the Comes on 30 Days' Trial mercury tube in a vertical position. A scale is next to be added to the ba- For full Information, without obligation, cheek No. 1 in the coupon below. rometer. On the title or index page of this Practical magazine you will find just the thing that is Complete Automotive Electrical Service Ls also a Big Moneymaker needed: an inch -centimeter scale. With with an IIB Universal Test Bench paste and paper, in your shop. ONLY $20 MONTH- a pen, or typewriter, jar Radio Advice LY brings you advantages previously revise the centimeter or metric scale so to be bad only with equipment cost- big $100 to $150 more. that it apparently reads 73, 74, 75, 76, 77, 78, 79 cm. On the inch scale, mark the Get five men's profits for one man's whenever work with an HB Portable Paint numerals 29, 30, 31. Paste both scales on Spray. The wonderful new paint a cardboard hacking, which can lie affixed method you read so much about. Paint automobiles, houses, barns, to the glass tube of the barometer with wire, garages, furniture, etc. Inex- 76 are you want it! perienced men doing better work so that the 30 and the marks exactly than old time brush painters. opposite each other. 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Mall the coupon below. placed in the right position behind the glass But more than anything, the fact barometer tube is by using another barom- that Radio News can present, far in eter such as an aneroid barometer, and then advance, money -saving articles, radio HOBART HIB BROTHERS fastening with cotton covered wire the paper helps, the newest circuits and the 5uu.essfuImanufactures -since1893 ^ scale permanently on the glass tube, so that latest trends, is a great factor in its BOX S38 TROY, OHIO both barometers read the same. Another popularity., Tear off Coupon and Mail Today method by which the instrument can be cali- The Radioist who has Radio News brated, or the scale placed in the right posi- directing and advising his actions has HOBART BROTHERS CO. tion is to wait for a clear, fair day when a set that cannot be outranked--. Box 538, Troy, Ohio weather reports indicate the barometer as Send me complete Information on the Items I've checked Radio News is ever to the fore. with your 30 day trial offer, easy payment terms, and in normal. Wire or affix permanently the formation on how HB equipment will increase my earnings. scale behind the glass tube so that the top It is interesting- 1 O One Day Battery Service Profits of the mercury column reads thirty inches 2 Electrical Test Bench Opportunities It is valuable- 3 Portable Paint Spray Business or 76 centimeters, whichever scale you pre- 4 D Better Automatic Air Compressor fer to use, English or metric. It is Radio through and through. NAME As stated before, the mercury column And every copy contains something, ADDRESS will rise or fall depending on certain con- of one kind or another, that you ditions. Refer to any weather book or almanac. should know. 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Radio Equipment Co., 548 S. Wells St., Dept.182 Chicago YOU THE SECOND TIME

Wrestling Boo FREE EXPERIMENTER PUB. CO., Inc. Learn wrestling at home from former world's sham Farmer Burns and Frank Catch. Free book tolls how. Secret holde. blocks. tricke revealed. Be strong. healthy. 230 Fifth Ave. 'New York City addle big men easily. Write for free book. State age. The well of the barometer. Note the slotted ara!?r floras 1 óoo', .763^,_i 't ay 72.;.,Or,sLa, Ee!. cork. Science and Invention for March, 1928 1055

The Case of the S-4 By H. WINFIELD SECOR (Continued from page 980) Achieve

As the naval officer interviewed by the writer stated, the only successful method of SUCCESS raising a submarine thus far established, is by the use of pontoons, as was the case of the S-51. in Radio Briefly explained, the method of raising a heavy and fairly delicate structure, such as a submarine, by the pontoon method, is New course gives finest to pass several slings around under the hull, and to these are attached on either side, pon- instruction obtainable G ales. Cal. toons sunk in place by filling them with "Gentle- water. To each pontoon there are attached You Can Learn at Home! men: 'ou may be interested one or more air lines connected to powerful pay from to know I have air compressors on salvage craft above. Good the start, received Japan and rapid advancement, and phe- Australa using your Eliminator. D. J. Mills." When all the pontoons have been put it (From letter of Nov. 28th, 1927) nomenal success-a life pro- Think of it! Performance beyond the capabilities place, the compressors are all started work- of many of the highest priced Eliminators-for only ing, and the water slowly forced from the fession of fascinating brain- $6.851 Is there anything in Radio to equal it. Every day such letters as the above prove the pontoon chambers, which naturally become work-that is what Radio thrills and wonders possible to users of the mar- more and more buoyant. With velous Townsend B Socket Power. Convince your- the proper holds for the man who knows self immediately at our risk. number of pontoons, the submarine is finally his subject thoroughly. Since IO Days' Free Trial lifted. 1909 Radio Institute of You are the Judge! Just put your name and ad- Many caustic comments in R.L.DUNCAN, dress on a piece of paper, pin a $1.00 bill to it and appeared the Director, America has trained thou- mail today. Upon arrival of the B" Socket Power daily press because large lifting cranes were Radio Institute Unit, deposit only $5.85, plus postage, with the of America and sands to become successful Postman. Try out for ten days-then if not more sent to Provincetown, and then left idle author of than pleased. return ft and purchase price will be refunded. without even attempting to bring up the S-4 several volumes in the many branches of Ra- from its watery grave. The reason these in radio. dio. Are you going to plod Townsend "B" cranes were not used, is because the sub- along at a thirty-five dollar a week job marine was far too heavy, especially in her when REAL MONEY is waiting for you water-logged condition, for the cranes to in radio? Socket ever be successful in lifting her. That was the statement made at the interview the New Course Finest Ever Power writer bad with the expert aforementioned, Prominent radio men have en- Approved and Passed by and he took occasion to nullify the sug- thusiastically greeted RIA's Radio News and Popular gestion of many civilian inventors by stat- new course as the most com- Radio Laboratories. ing that it was quite impossible to have plete and up-to-date offered Townsend Laboratories today. All this first- quality 713 Townsend St., BALANCE attempted dragging the S-4 into shoal water. equipment is furnished FREE Dept. 35 Chicago. Ill. C.O.D. This was so because of the great distance, WITH THE COURSE-parts for making many practical and most important of all, because of the radio circuits and the Peerless great weight of the S-4. Besides, the pull- Signagraph for code instruc- ing strains might have ruptured the sub- tion. q5io Weeki marine. 425 Many people made the suggestion that Charging Batteries magnets should have been secured to cables t and lowered into contact with the steel hull, dsiStarts You and the submarine thus raised completely Let me show you how and safely. It was absolutely impossible to to make big money do anything like this for the simple reason Q _-Q right from the start. that the magnets would have pulped the I've prepared a FREE book explaining all details. First plates off the framework of the hull, and week's profit pays for ail equip- the only way ill which magnets could have ment. You can get all the battery been used at all, would have been if the sub- charging business in your community with my marine huge iron blocks mounted at Service Station Charger-it's years ahead of or- had dinary chargers handles 50% to 70% more equally divided sections along the top of batteries. I explain- everything-start you in a the hull. This of course is quite impractical. business of your own and put you on the way to big money. Write for FREE BOOK. VACUUM CUPS RIA backed by RCA, G -E C. F. HOLMES, Chief Engineer, Dept. S.I. Independent Electric Works OTHER inventors suggested the use of and Westinghouse 6116 R wood Ave. Chicago, lit. rubber (or rubber rimmed steel cups) You get all the benefits of instruction conducted vacuum cups placed on the lower ends of by RCA and sponsored by RCA's associates, G -E cables sent down to the scene of the wreck. and Westinghouse. Our employment department When the divers had placed these vacuum is at the service of graduates. cups in contact with the hull, the air was to be exhausted from them through )lose lines Study at Home! FREE --Radio Catalog you can STUDY AT Te Dealers-New, illustrated 1925 Wholesale Radio running to the surface craft above, and in Moreover Sesosenilerr Catalog gives lowest priers; on accessories, kith, packs, this way the wreck finally raised. The same HOME-when you please and as OSA el parts, and sets. Features master-built single control radio long as you please. sets for both battery and all electric operation. Full technical objection again becomes effective; showing of "A" and "n" Eliminators and thousands of This new booklet describing the other great values. Write on business letterhead for this the vacuum cups would hold to the steel course is just off the press. If you free book today. plates that they were in contact with, and want to learn more about the well Hamilton -Carr Radio Corporation rip the plates from the whole frame. ine is fascinating W. 382 Chicago, III. pprofessiionposisend thtions coupon now 711 Lake Street Dept. for your copy. MARKER BUOYS- FOR SUBS OF AMERICA ? AS one of our enterprising congressmen RADIO INSTITUTE 'CanYouSellGasat5cPerGa1 New York City If so write me quick. My Distributors make as high as $3,000.00 pointed out in the daily press, an order Dept. G.3 326 Broadway, per month with amazing new thermostatic car- had been put through some years ago calling buretor device. Let me show you how. for the installation of a marker buoy on RADIO INSTITUTE OF AMERICA, Dept. G-3 SEND FOR FREE TRIAL each submarine, this buoy to be available in 326 Broadway, New York City Proof of astounding success and my $15.00 cases of emergency, so that it could be re- Dear Mr. Duncan: a day Guarantee to Distributors. leased and floated to the surface, attached Please send me your new catalog. I want to Frank Andrews, Pres. BLANCKE AUTO DEVICES CO. by a cable of course to the vessel below. know more about your new radio course. 154 E. Erie St. Dept. 863-C Chicago, III This congressman raised the question as to Name when the order for installing these marker Address 2. i THIS CLASS PIN 30 buoys was rescinded, and aside from this 12 or more, Si,. ver plate, Single pivaauc ta. oho),2 cule phase of the argument in regard to the S-4, p, amet, 3 letters, date. Sterling Silver, l t or more 50c ea. Single phis 60e. ea. Free Cat. ahow, Pins,Ringa,Emblema 25c to 88ea. a few very interesting and vital questions 685 METAL ARTS CO., lac, 713 Portland Ave., Rochester, N.Y. arise in regard to the use of buoys. 1056 Science and Invention for March, 1928

In the first place, hundreds of inventors have sent in illustrated suggestions and plans for crew salvage buoys. In the more elabo- High School rate plans of this type, the inventors specify that each of the live or more water -tight compartments in a modern submarine, should COOKERY have one of these crew -saving buoys ; some Education inventors suggesting a steel buoy capable of holding one man, and others again speci- in Question and fying a buoy to hold three men. The first serious objection to these crew rescue buoys, Answer Form is that they would take up a lot of room on It's FUN getttngyour the submarine, where the space is already High School Educa- a alone tion this new easy at premium. This one objection way. Just read fascin- practically settles that suggestion. ating questions and answers! These The next form of buoy we come across, 1 welve wonderful books is the marker buoy. The first application of give you the essentials the marker buoy is for use when a sub- of the complete 4-year High School Course. marmq has sunk, out of control, so that the They qualify you for buoy can be released by suitable wheel gear, a Certificate. and allowed to float to the surface. Here it would serve as a marker to passing vessels Get Your Education In Spare and indicate that a submarine was lying in Moments at Home distress at that point. Some inventors sug- A few minutes a day of entertaining reading lits you for bigger gest that this marker buoy could send out greater Social advancement.n You learnn;even' 311ggh subject: English; Fre ch Spanish; y; flashes of light in Morse code signals as Modern, ºo American History; Literature; Biology; Physics well as fire rockets, and could also send out Algebra; Economics. - sound signals in short and long blasts cor- A Remarkable Bargain responding to Morse code signals. Your eotplete High School Education costs you only $15.85 on easy monthly terms. "The greatest bargain in education The naval expert with whom the writer ever offered," students say. Ezamine the 12 books FREE. talked over this idea, was in accord with SEND NO MONEY No money In advance, no the plan for marker buoys. C.O.D. Simply return them in 5 days or send $3.85 tine payment and $4.00 monthly for 3 months. (Or only $14.27 if you pay In regard to these buoys, there is one Ida Bailey Allen's cash after examination.) Send name and address NOW. thing that the civilian inventor always for- HIGH SCHOOL HOME STUDY BUREAU Delightful Book of 31 Union Square Dept. 243, New York, N. Y. gets, as has been pointed out by the naval men. In the first place, unless a fairly recipes strong steel cable joins the buoy to the sunken submarine, the cable will he ruptured menu (*WIiZ as the buoy bobs about on the surface, a especially if a storm occurs. In the second diet place, if a fairly strong cable is used, then conduct of house- NAMI the weight of the cable comes into the question, and a larger buoy must be used in hold, buying aids, Sedan order to be able to rise with the added weight of this heavier cable. Now again if etc. a larger buoy is used, then quite a bit of or valuable space must be sacrificed in the sub- Special Price $1.98 marine hull to accommodate it. There are *1400 other objections of course to marker buoys, Regular Price $2.25 in cash in that they may fail to rise at the desired Someone who answers this ad will receive. time, or the relcasei gear may become cor- IDA BAILEY ALLEN, in this absolutely free, a fully equipped De Luxe Model Nash Sedan, or full value in cash if pre- 14 roded and jammed so that they do not book, has a cook book ferred ($1,085.00). In addition to this Nash written Sedan we give away,'absolutely free, a latest operate when sorely needed. One of the more. This is a thor- model Chevrolet Coach or its cash value 1 Navy Department experts at Washington -yes-and ($595.00), a Brunswick Panatrope Phono- ough discussion of the subject, graph, a Six Tube. Single Dial Freshman 10 stated that such marker buoys were officially Radio, a Corona Portable Typewriter in time from festive desserts to feeding many other valuable prizes and Hundreds -of frowned upon, for the reason that Dollars in Cash. 8 of war the buoy might become released in the sick. Solve This Puzzle some way and float to the surface, when a The numbers in the squares to the right spell was hiding on the bottom of the It is a practical aid that every two words. The alphabet ie numbered. A is 1, 19 submarine ß is 2, C is 3, etc. Can you make out what the sea. This would disclose that a sub -sea household should have. The :wo words are? When you do this, send me 5 our answer right away. It may mean winning craft was lying at that spot; as soon as hostess will find it invaluable in äe Nash Sedan or 31,4.00.00 in cash. the buoy was spotted by the enemy, a quan- planning the small house party 4 on $315.00 Cash For Promptness tity of depth bombs would be dropped or the wedding banquet. In addition to the two automobiles, the 1 the scene, anti the submarine wiped out. many other valuable prizes and llundrede of Ida Bailey Allen is a nationally Dollars in Cash, we are also offering a Special The author does not agree with this Prize of E315Á0 in Cash for Promptness. First 14 official opinion, and believes that a marker known expert of Domestic Science. prise winner will receive 31.400.00 in cash, or the Nash Sedan and 3315.00 in cash. In case of ties buoy should certainly be installed on every When she writes, it is well to incor- duplicate prizes will be awarded each one tying. Ge and posi- busy right away. Solve the puzzle and Bend me you submarine, and that a satisfactory porate her many ideas and breadth answer together with your name and address written tive release gear can certainly be designed, Plainly. EVERYBODY REWARDED. Address of experience into your own. M. L. BOEING, Dept. 3793 so that there will be no danger of the buoy 323 So. Peoria St., Chicago, Ill. being unconsciously released in time of Also it should be possible to design it 2500 RECIPES SALESMEN ! $100 WEEKLY war. SELL. COX HOLDFAST SCREWDRIVERS so that it will hardly ever fail to rise to 1001 PAGES the surface. Special Price $1.98 A well-known New York City inventor, Regular Price $2.25 suggests that . who has studied the problem, The Household Through the every submarine should carry a buoy marker iffee, Eyes of an Expert especially designed for use when rising to Also made to use In Yankee or Ratchet Handle. Sells on sight to is no it Delivery Garages, Radio Men, etc. Self Holding, Self Releasing. Sample the surface. There doubt about Use this Coupon-Immediate and proposition, fine. S. J. COX, Dept. J, Franklin, Pa that at the present time it is a very weak that there is point in submarine operation, CONSRAD CO., Inc., easily recognized signal by Ko1ME? no definite and 230 Fifth Ave., New York. N. Y. WANT WORK which ships in the vicinity may know that Gentlemen: I enclose $1.98: please send me ru 520 to 550 a wed: reto:; teng photos -men one copy of Ida Bailey Allen's COOK BOOK. or women. No selling or canvassing. we teach a subsea craft is about to appear at the sur- you at home, furnishing working outfit and calls for light employment service. Write today. Artcraft, face. This engineer's design Studios, Dept. 43, 3900 Sheridan Rd., Chicago and sound signals in the Morse code, giving NAME...... a pre -arranged signal, by which sea -faring Your Own men in the vicinity would know that a sub- ADDRESS PrintCards. Stationery, Circulars, Paper, etc. Save marine was to come to the surface in say, money. Print for others, big profit. Complete CITY outfits 58.85. Job press $11. $29, Rotary $149. All two or three minutes at about that spot. It easy, rules sent. Write for catalog presses type r-07, .nrldap, Cons.. was the opinion of one of the naval Science and Invention for March, 1928 1057

officers to whom this scheme was explained, that when the submarine was moving through the water horizontally and gradu- "\,» ally approaching the surface, that the buoy would be dragged at a downward angle and would never reach the surface. We do not 4111414 *ens think that this is the case, however, if the of Uokn it1lsical Superiors? 4q!<. buoy is properly designed as to size, and fitted with the proper size of cable. Do you look with envy and C1iI0 hatred upon the man who W00, out in a crowd the stands Another suggestion for rising signals for picture of health and vigor and strength -the real man- use on submarines takes the form of calcium ly fellow? Do you sneer at NEW JER.0'EY ,li carbide bombs, which can be released from the peppy pugilist, the powerful wrestler, the AND /" a special gun on the sub -sea craft when she speedy runner, the grace- is about to bomb ful dancer-do you call arise, this chemical ex- them "big stuffs?" THE LOVELY ploding and giving a smoke and flame signal Beware, man, if this is on the surface. It has been stated by several your feeling toward strong healthy men --you are filled experts that submarines are supposed to give with jealousy. You feel a rising signal of short on the your own weakness. In your three blasts heart you wish you were LAUPEL under water, sound wave oscillator; but if a like these fellows. You want to be strong and vessel such as the coast guard destroyer healthy. You want to com- Paulding is not fitted with under -water lis- mand the attention of men and the admiration of wo- HOufE tening devices, it is doubtful if these signals men -you wouldn't be half a man if you didn't. You will save a submarine, and the S-4 accident know your own weaknesses seems to prove the point. even if you are hiding them from others, and you envy One those who are your super- expert pointed out that if the S-4 did iors -those who seem to get give a rising signal on her under -water oscil- the center of the stage MI DWI NTER GOLF wherever they are. They are lator, this signal could have been heard on the "life of the party" al- the Paulding, even without under -water ways, everywhere. They are WINTER .1PORTJ the fellows who get all the "ears ;" but the navy officer the writer inter- promotions, all the good CONCERTI-DANCING viewed did not think this possible. He fur- jobs. ther stated that although the Paulding, now There's No Place in use. by the Coast Guard service was an For Weaklings old naval vessel, -and you needn't be a when these naval boats weakling-You needn't be are turned over to any other service than jealous- you needn't have physical superiors -you can that of the navy, the sound -sensitive devices, STRONCFORT be strong and healthy your- HO'TEi. such as under -water sound wave listening Builder of Men self. You don't have to go A PERFECT on ailing and complaining. and sending instruments are removed. You don't have to be ashamed of your weakness-even WITH !REMARKABLY though you know better than anyone else what brought you to your present condition. There's a way out of your dilemma. You are no different from LOW RATE.' ESCAPING THROUGH TORPEDO TUBES thousands of others who have gone the pace, dissipa- ted their strength, and are paying the penalty. You ONE of can be put back on your feet. You can be made a the orthodox rescue methods sup- 100 per cent man-energetic, vigorous, alert, ambi- posed to be available on submarines, tious, happy-a respected husband-a proud father- it's all up to you, it's for you to say whether you are was the escape of the crew when trapped going to become a shiftless, useless derelict, or an through the torpedo tubes. This is feasible upstanding man among men. UNDER in many instances, when compressed air is available for shooting a man out of the STRONGFORTISM RENOWNED tube, but in the case of the S-4, due to the Science of Health and Strength severe damage caused through the ramming Do Wonders for You by the destroyer Paulding, the men trapped -Will J'A LTZ MAN It was through the methods I used in developing my in the torpedo room in the forward end of own body that I won the world's record as the finest specimen of muscular development and champion- MANAGE.M ENT the craft, did not have the use of compressed ships in feats of great strength, in Europe and in the air lines and air storage tanks in the com- United States, that I constructed the science of STRONGFORT ISM. It is through it that I reclaim partment to the rear of their position. wrecked and weak men, make them into new beings, and give them a body and arms of which they can No drugs Also it must be remembered boast. I require you to use no apparatus. that the S-4 or medicines are prescribed. No inconvenient hours landed on a very muddy bottom, and that are required. Only a little of your time in the privacy of your own room is necessary to follow my easily un- the outer openings of the torpedo tubes were derstood instructions and, oh man, how glad you'll be covered mud. One of the suggestions that you listened to me, once you start on my course with as alive. made was that the men might have escaped It means a new day for you, that's sure you're through the torpedo tubes one at a time, a Send For My FREE BOOK man opening the inside door, crawling into I've packed the experience and research of a lifetime of physical and health building into my startlingly inter- the tube, and then when one of the crew esting book, "PROMOTION AND CONSERVATION opened the outside man in OF HEALTH. STRENGTH, AND MENTAL EN- door the the tube ERGY." IT IS PRICELESS. could crawl out and start swimming to the In it are plain facts that will astonish you and help PERSONAL surface. As long as a salvage craft was you out of your sorry plight. Just check the subjects on the free consultation coupon on which you want Appearance over the spot, he might be in luck, for he special confidential information. certainly would have a bad attack of the Copy TODAY Is now more than ever Send For Your the keynote of success, "bends," due to the rapid change of pressure both In social and busi- as he came up from a depth of one hundred ness life, Bow -Legged and Knock-Kneed feet. Providing the salvage boat, such as the RTIRONG OOT nisTrrUTE men and women, PLIONEYSICALST.ANRONGFORT. DIIRECTOR. young and old, Falcon, was on hand with a recompression ALTH both U.S.A. will be glad to hear t hat chamber, in which the man could be placed, DEPT. 442 NEWARK. NEW JERSEY. my new appliance will Buccesgfully straighten, so as to adapt his lungs to the normal atmos- within a short, time, pheric be __CLIP and SEND THIS COUPON -- bow-leggedness and pressure, he probably would knock-kneed legs, safe- saved. The last two men would doubtless FREE Consultation-Absolutely Confidential ly, quickly and per- have lots for this method of escape; Mr. Lionel Strongfort, St rongfort Institute, Dent. manently, without to draw 442, Newark, N.,!.: Please send me absolutely free pain, operation, or discomfort. Worn at night. My new and moreover it is the opinion of several n,y ropy of your book. "PROMOTION AND CON- "Lim-Stmitner," Model 18, U.S. Patent, is easy to adjust: SERVATION OF HEALTH, STRENGTH AND Its results will soon save you from further humiliation. and engineers and naval men, whom the writer MENTAL ENERGY." I have marled (xi before improve your personal appearance 100 per cent. (Model 18 interviewed, that it was practically impos- the subjects in which I ant most int erect ed. Is not Iike.old-fashioned splints or braces, with bothersome ..Colds ..Weak Eyes ..Weak Heart straps, hard to adjust, but a scientific, modern device of for a man to escape in this way from Strength proven sible ..Catarrh ..Increased ..Great nmrlt, used and recommended for the last 7 years by he would doubtless be ..Asthma Height ..Lung Troubles physielare everywhere.) Write today for particulars, testi- the torpedo tube, as ..Headache ..Flat Chest ..Poor Circulation monials. and my free copyrighted physiological and anatom- drowned from the inrush of water (and mud .. Rupture .. Despondency .. Round ical book which tells you how to correct bow and knock- ..Thinness ..Emaciation Shoulders kneed !ego without any obligation. Enclose dime for postage. in this case) as the outer door was opened. ..Pimples ..Rheumatism ..Skin Troubles M. TRILETY, He could not hold his breath very long, so ..Insomnia ..Nervousness ..Stomach SPECIALIST ..Overweight ..Constipation Disorders 1604 L, W. U. Building Binghamton, N. Y. the water could not be admitted slowly; ..Weak Back ..Short Breath ..Muscular further, he would doubtless be drowned by Development thus admitting the water in slow fashion. ..Private Ailments Name One of the Navy's schemes for supplying food and oxygen bottles to the crew in Age Occupation t cnn moire a good penman of you at home during such a predicament as the men trapped in Street your spare time. Write for my FRE s BOOK, "HOW TO BECOME A GOOD PENMAN." the torpedo room of the S-4, was explained Your naine elegantly written on a card If you City State enclose stamp. Write today. F. W. TAMBLYN, to the writer. This scheme, which was to 424 Ridge Bldg., Kansas City, Mo. have heed tried at Provincetown, if the 1058 Science and Invention for March, 1928

signals from the crew had persisted a little longer, was to force open the outer door of the torpedo tube, and place some properly High School protected food and oxygen bottles in the The torpedo tube, close the door (divers doing Possibility of the Course in this work of course), and then signal the crew to open the inside door. When they Great Impossible- 2 Years opened the inside door, there would be quite his simplified, complete High School Course-speciallyprepared for home study a little ,ater released into the compartment, by leading professors-meets all require- but this would pass into the bilge space be- , clients for entrance to college, business, and low the floor of the compartment, and then Other leading professions. one of the men could crawl into the tube !rf0 ii I h e r Over 200 noted Engineers, Bus - CoursesipnessRen,andEducatorshelped and safely obtain the oxygen bottles and repare the special instruction food. A variation of this scheme, as the 'whichyou n fed for success. No matter what your Inclinations may be, you can't hope naval officer explained, was to drill a hole to suoceed without specialized training. Let in the outer door of, melve you the practical training you need. the torpedo tube and American School connect an air supply hose to this opening. Drexel Ave. ft 58th Street Dept, H.326 Chicago SEVERAL suggestions for drilling a hole through the steel the If Not Satisfied wall of submarine Money Back When You Finish in order to safely connect an air line to the American School, Dept H-321 Dreiei Ara and 58th St.. Chicago torpedo room, for example, were suggested. Send me full information on the subject checked and the how you will help me win success In that line. On second day after the S-4 went down, Architect Electrical Engineer a small steel bell with drilling attachment Building Contractor General Education inside it, was sent to Provincetown by a Automobile Engineer Lawyer Civil Engineer Mech. Shop Practice well-known civilian concern. Coincidentally Structural Engineer MechanicalEngineer a similar idea was developed by the author, Business Manager Steam Engineer and it is shown in the illustration presented C. P. A. & Auditor Sanitary II Heating Bookkeeper Surveyor & Mapping at the start of this article. By means of this ..._.Draftsman&Designer » High teasel Graduate drilling bell, which can be held against the . . hull !either by water pressure, or else by .)'t,/: .' Name electro -magnets, or as one of the navy ex- nG.Wtil=; tairl l_ liel,lti Adenas perts suggested, by fusing it fast with an under water oxyacetylene torch, a hole could be safely drilled through the hull wall of the compartment containing the living mem- CHEMISTRY bers of the crew. As will 'be seen from the Complete, practical home-study featuring courses prepared by some of the illustration, it is a simple matter to supply best-known chemists in this fresh air through the bell from the salvage country, including craft above; also liquid food could be ALLEN ROGERS, B.S., easily "When the Sleeper Wakes" M.S., Ph.D.-Head of supplied through a hole in the center of the by H. G. WELLS Department of In- drill, or by some other simple means, and dustrial Chemistry, oxygen could be Pratt Institute; L. transmitted either down the M. TOLMAN, Ph.D., air tube, or from separate tanks attached "The Moon of Doom" Vice-president directly to the bell by divers. United Chemical by EARL L. BELL and Organic Prod- Another idea would be to have a small UCtS CO.; BRADLEY steel cylinder to screw into an emergency ' STOUGHTON, B.S.- outlet fitted in the hull, and to one side of AMAZING STORIES Head of the De- this partment of Metallurgy Lehigh University, and cylinder, containing concentrated food QUARTERLY OWEN L. SHINN, Ph.D. - Professor of Applied and oxygen bottles, an air hose could be Chemistry, University of Pennsylvania. readily connected. To pass the food and Mail Coupon for Free Booklet oxygen supplies to the crew into the opening, INTERNATIONAL SCHOOL OF CHEMISTRY 1 the diver simply turns a handle on the end 50c Division of the International Correspondence Schools of the cylinder, as the illustration shows. STORIES of unusual interest for the scien- Box 6225-E. Scranton. Penna. tific trend of mind. [.---...---Without cost or obligation, please send me full I F a sufficient quantity of air could have Places that have been dreamed about details of your home -study course In passed throughout the ages-out in Analytical Chemistry Metallurgical Chemistry into the entombed men, Simon the great un- Chemical Engineering Short Chemistry Course Lake's idea of rescuing the crew then be- known-beyond the pale of scientific re- Industrial Chemistry Pharmacy search. This is the appeal of the AMAZING came a very good one. When the air pres- STORIES QUARTERLY! Nomo sure became great enough inside the sub- Here, the visions of the world's foremost marine, to counteract the pressure writers of scientifiction are viewed: Address of the There is H. G. Wells and Earl L. Bell. J water, then Mr. Lake, famous builder of Certainly scientific men need no intro- submarines, stated that the divers could burn duction to them. Dr. Miles Breuer pre- a hole sents his "The Puzzle Jewel." Edward through the steel hull of the sub, pass R. Sears his "The Atomic Riddle." in diving suits to the crew and let them come Clelland Ball his "The Gravity King," BUILDY°Hóord"MOCK out through the hull one by one. As they and numerous others of note. came out onto the sea bottom, a line would Every story is a vivid picture of interest Profitable spare time work for winter. be fastened to you. Turn idle hours intowelcome dollars to them and they could be hauled building clocks from our instructions. slowly to the surface in the same way that 150 pages, large magazine size, We furnish plans, instructions, blue- the divers ascend, in order to become accus- 9 x 12 inches prints, works, dials and all materials at surprising low prices. tomed to the reduced pressure as they approach the surface of the sea. Amazing Stories Quarterly You make a big profit building artistic clocks for your friends. Simple chemical purifiers for removing carbon dioxide from the air should be Banjo Clocks, Mantel Clocks, placed 50c Beautiful Grandfather Clocks in each compartment also; and some im- Absorbing-In teres ting-Thrilling with Chimes. Complete works as proved method of sending signals by sound USE COUPON low as $5.00. Many styles, all waves from the submarine through the water, Note-We have on hand a few copies of prices. ASK FOR OUR ATTRAC- AMAZING STORIES ANNUAL, containing TIVE FREE BLUEPRINT PLAN in the place of hammer signals should be Edgar Rice Burrough's famous 'The Master AND CATALOG. provided. Mind of Mars." Write us and enclose 50c. for If the men in the torpedo room immediate delivery, before they all go. of the S-4 had had diving helmets American Chime Clock Co. available, 1679 Ruffner Street, Philadelphia they could have opened the inner door on EXPERIMENTER PUB. CO., INC. one of the torpedo tubes, and also the outer 230 Fifth Avenue New York, N. Y. door, donning the helmets beforehand, of WA1l;ri course, and then worked DIRECT FROM their way out from EXPERIMENTER PUB. CO., INC. SWITZERLAND the flooded compartment, through the tube 230 Fifth Ave., New York City and up to the surface, Gentlemen: Kindly mail THE AMAZING with the help of the STORIES QUARTERLY immediately. En- guide lines and the salvage divers. closed is 50c. Either a gas flame, a mechanical cutter or other special tool should be provided in Name each compartment, for the purpose of cut- hole Address Radium Dial _ t Silveroid. Cushion ting a through the wall of the sub- Jeweled Movement - -- Shaped Case marine large enough to pass a man ; in the TM. bony guaranteed watch\ cannot be manufactored in Ameriea -torleaethan'l2 Mate Genuine leatteeetrau. Aecerate--durable--handsome. event that City SEND NO MONEY. Pay on delivery Sass pine postage. FEDCO these self-contained diving hel- U.S. evoke agents. S61 Broadway. New York City Dent. W-17 mets are carried in each compartment. Science and Invention for March, 1928 1059

We are in touch with the best and most reliable eeilaols in America. If you are interested 1* art. engineering. electricity. radio, aviation. or ants kind of Dueness training, we wile help you find what you want. Please enclose 10x. to cover cost of postage and receive advice of prominent school expert. Ad- dress School Dept., P.CS, 9 East 46th St., New York. SCHOOLS Home Study and Resident Learn electricity at home through complete, practical Courses written by well-known electrical engineers. Indorsed by Edison and 1.e to Yer Hour Steinmetz. Write for Free Booklet. INTERNA- $7.00 for TIONAL CORRESPONDENCE SCHOOLS. Dept. 1228. Scranton, Penna. Your Full or Spare Time Learn Electricity In Los Angeles. Tech- Cash In Advance for Spare or Full Agents! Men and Women. Make big nical practical training qualifies You for respon- easy with elble position. 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Amazing 512 page book-"SafeCounsel, ' $5.00 as special advertising offer. Only limited tells the truth about sex. Explains the Laws of World's longest wearing suits, 31.2.5(1. Amaz- number of pupils accepted at this ridlculouely No Experience Or Capital Needed. Sell the Love-Ilte. Scores of Intimate subjects. ing wear demonstration makes hig, steady low price, so mall a Five Dollar bill TODAY to Taylor RainProof Cape and Women's Hats to 104 chapters, 121 Illustrations. Send no money sales certain. Write today for Free Kit, St. Johns System. 418 St. Johns Place Suite 2C. friends, neighbors, etc. Make $75.00 weekly. -Write for a copy We'll send our regular full starting Instructions. Nogar Clothing Brooklyn, N. Y. Money back It not satisfied. Expensive samples and outfit tree. Taylor Cap $4.00 Gift Edition. Pay postman only $1.98, Mfg. Co.. Dept. CS -3, Reading. Pa. Mfrs Desk F-4, Cincinnati, Ohio. plus postage upon arrival. Satisfaction guaran- Agents -$300 Month. Sell Guaranteed MONEY SAVING DEPT. Free Outfit With Actual Samples of Bos- teed. Catalog Free. Herbert Wilson, 800 N. Silk Hosiery. Must wear 7 months or replaced. tonian broadcloth gets quick sales for our Clark Street, Chicago, Dept. 4700. New selling plan. We furnish auto. Free silk "A bargain or your money back" nationally known Bostoan Shirts at three Bankrupt and Rummage Sales. Make hosiery for your own use. Write for samples. For special service, please mention name for $8.95, postage paid. Liberal cash com- $50 daily. We start you, furnishing everything. Betterknit Textile Company, Silk, 835, Green- of this magazine when ordering mission of $1.50 on each order of three shirts Permanent business. Free details. Distribu- field, Ohio. big profits Send 25c for Five Issues of French earns for you. Bostonian Mfg tors, Dept. 279, 429 W. Superior, Chicago. POLMET POLISHING CLOTH. -Cleans Humor, a weekly magazine full of live, Co., Desk 8M2, 72 Summer St., Boston, all metals, enthusiastic attention, sells fast Macs., Established 1883. We pay women $6.00 an hour to wear gets clean Illustrations and jokes right from -, exquisite Fifth Avenue dresses and show at 25e; sample free. F. C. Gale Co., 99 Edin- France. Newsstand Price 50c, French Humor, $15 a Day Demonstrating Amazing New them to friends and neighbors. Experience boro St.. Boston, Maas. 230 Fifth Ave., N. Y. C. kind men's of hosiery for largest company in busi- unnecessary. Write today to Fifths Avenue Women Representatives Wanted. New No more bother with "B" Batteries. Get ness. Powerful selling outfit Absolutely Free. Styles. Dept. 1003. Scranton, Pa. Invention prevents shoulder straps slipping. No perfect reception from light Per- Write for exclusive territory Superwear Hosi- more discomfort. Women adore It. Write for direct socket. ery Co., Desk C-90, Minneapolis. 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"Tell me about your spare time offer" and ash, trap etc. For details, write Norton,270 C.O.D. for balance ($3.95 plus few cents post- $1,000.00 Reward If this is not the great- state how your home la lighted-Gas-Elec- Temple Court, Denver, Colo. age) Carroll Sales Co., 3242 Boudlnot, Cin- est money -making house to house proposition trlclty-or Oil. We Start You Without A Dollar, Soaps, cinnati, Ohio. ever known. N.R.G. tablets wash clothes Sell Men's Fine Sults (extra trousers Extracte, Perfumes -Toilet Goods, ex- Special until May 30th! Eleven pocket In 10 minutes without rubbing. Free Samples. tree) for $16.95. Commission $4.00. $90 a perience unnecessary. Carnation Co. size detective books. Thrilling) "Valley of Miss- N.R.G. Co., P232, W. Superior, Chicago. week for you, also tailored pants, $3.95 ($5.00 Dept. 593, St. Louis, Mo. ing Men," "Creen Eyed Monster" and nine Old estab. mfg. co. gives you credit; value). Big extra commissions. 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Cigar Stores Novelty Jackson Blvd., Chicago, Ill., specialists in now and get big tube of New Quick Shave guaranteed for full yearl Large swatches and Co., Dept. PX, Peoria. Ili. direct selling, mall-order and poultry advertis- Cream free. Mail only $1 to Carter Distributors outfit free. Write quick! Palmer Clothing Free Ad No. 33, over ing. Service circular on 3242 Boudmot, Cincinnati, Ohio. Mfrs.. Dept. JW-6, hattanooga, Want Catalogue and catalog request Tenn. 1.000 publications. Many combination offers. Agents; 500% Profit Free Samples Gold If you need money and want to make it Agents-Just Cott $8.88 for Men's Publishers rates, place anywhere. Brinker- Sign Letters for Stores and office windows. at home In spare time get my big Illustrated Suite) Anyone can sell! Commission $3 hoff, Inc., 37 W. Van Buren, Chicago. Ill. Easily applied. Large demand everywhere. book of 87 tested plans that show you how to In advance! Free Sales Kitt 8t}S Company. New Patented Self -Feeding Pencil! 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All wool and pure worsted suits not be manufactured In America for less than Lincoln Place, Brooklyn, N. Y. and topcoats at $18.75 with $3.75 to sales- $12.00. We sell for only $3.99. Send no money. Send 25 Cents for a $1.00 Pocket Cigar man and 7% to manager. Outfits free. One of Pay on delivery. Money back If not delighted. Lighter and learn how to make $10.00 0 the largest companies In America. We back day Easy. Sells on sight. Particulars FREE. IS IT'S NOT HERE WRITE UM every garment. Canterbury Tailors, Dept. Handell Company, St. Johns Place, Brooklyn, Rapid Mfg. Co.. 799C Broadway, New York. Here is a new service for the convenience of M-7, 22 West 22nd Street, New York. N. Y. our readers. If you are looking for certain articles Dress Up! Get three beautiful Rayon Why not sell us your spare time? $2.00 not listed, write P. C. S. Information Dept., High grade managers with good Silk Ties In latest Parisian Patterns by mailing an hour $19.70 daily easy full time. 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Money back If not delighted. 1060 Science and Invention for March, 1928

Thought Konzentrator- Latest Swindle WI N1OOO (Continued front page 981) Wkatè achievements. Professor Mueh has treated some dour troub 80,000 men and women during the last few years for weak mental faculties, and Konzentrators is the result of his enormous experience. It can, therefore, be accepted as at least worthy of a trial, and those who have ventured to acquire Here's the answer this wondrous psychic accessory are all full of praise for the unexpected benefits they obtained. HOW TO USE THE KONZENTRATOR to any Radio Noblem First dampen both temples with a little water; then breath several times (3 or 4) upon the center capsule (perforated) containing the concentration chemicals which the warm moisture in your BEFORE AFTER breath changes into a battery. that ever existed Here's how Gregory And here he is thirty The two antennae should just cover the temples Paradise looked before days later-his body and the whole apparatus should be placed lightly he started Titus training I covered with muscle Here's my latest prize winner! $1,000.00 in cash and solid gold medal awarded to Gregory Paradise for the greatest Improve- ment in physical development. Another amazing demonstration of Titus Training! In March "Radio News" YOU'RE NEXT ! YOOUR MúMUSCLES it a wow! Dec. Fellows. was On 31st G R O W ! Encirling the World on a Two -Tube Set- my 1927 muscle bulling contest ended By Magee Adams with a bang! Physical culture authorities were amazed at the Charles startling results of Titus Training as shown in photographs and Bridge by Radio-By G. C. B. Rowe measurements, before and after, of applicants all over the country. The Screen Grid Laboratory Model Super- Now we're off on my 1928 Prize Contest. YOU'RE NEXT! Ernest R. Pfaff. Just give me 30 minutes a day for 30 days. See how I changed heterodyne-By that lati above from a puny weakling into a GIANT of muscle? A Four -Tube Screen Grid Receiver-By I'll do the same for YOU right in your own home! Hugh H. Knowles CLES The Distant Signal A.F. Amplifier-By FREE BOOK INIMUSC E Gerard J. Kelly Write today for my wonderful book on building muscles. Also details of 1928 Contest. No cost, no obligation. Controlling Volume in Your Receiver- The one 105 East 13th Street, By John B. Brennan, Jr. and only TITUS Dept. A -I24, New York, N.Y. The United States-A Broadcast Studio- By Joseph Riley The Action of "B" Socket -Power Devices PLUMBINGHEATING -By John B. Brennan, Jr. What Constitutes Tone Quality ?-By R. N. Install Your 010n-Save Half Auble Lowest wholesale prices on highest quality Grade A goods. Any Handy Man can install his own Plumb- 1 EDITI01 !ng and Heating BY OUR around the head without any pressure whatso NEW EASY METHOD. Get -ver. When the body heat (in a minute or two 8 the best and pay only a little has warmed up the Konzentrator you retire to a each month. quiet place, and comfortably teated, relaxing fron JQ tr Send for FREE Book. head to foot, thinking practically of nothing, you , New bargain catalog lust issued. With allow your soul to float away towards the IN ire our cut-to -lit systems you save waste FINITE, letting it vibrate into the Harinoniou material and high labor cost. 50 years will return to its mortal she! esc.tos home farmers. Cosmos, whence it roo1 of and mechanic° ilioDollar equipped with new thought -power, ready to re !An&ArisvVe back up our Bonded Guarantee. FREE book especially the neurones weeyou the whole story. Write for your copy create every body cell, ar. our brain nerve cells which we use up by our ,e1 wasteful thought action. You wear the apparatus 116 Pages-9 x 12 Inches OVER 6 for about ten minutes. You will then feel in- 50 HARDIN-LAVIN Co.18 spired and roused to activity. Do not resist it. Be prepared-This means but 50c, YRS. 104-14 West_ Pershir.gR d., Chicano. III Get busy with whatever work you have to do. and it is well within the means Notice how eager you are to take up that task; everyone. to write that letter; that brief; that sermon; of PHOTO ENLARGEMENTS that poem; that music; that book; that scientific Size 16x20 inches treatise, or whatever your professional work may 1001 RADIO QUESTIONS length require for you. Magically new and original oro buspricefrm.oeeuulplel C AND ANSWERS -50c name.. ideas come to your brain at the right moment enlargements of aanals,ÿyar1 dynamic. of group picture. Safe re- and you are wonderfully turn of your own original (Please takg care of your digestive organs. Be THESE questions are the ones photo guaranteed. regular in everything; avoid systematic toximea, SEND NO MONEY enapehotl(panyelO' by which your brain is naturally affected. Con- arising every day of the year and within a week you will receive your beauH- sult your physician in this respect.) guaran- not reg- -they are the ones that are teel d madÌein. Paypostman 98e plus pose -- If you desire quick thought -results do ne send $1.00 with order and we pay portage. or skeptical attitude, saying to wt< ister a negative costing you money through lack Special Free Offer ,1 yourself: Now, then, let's see what this thing is will send FREE a hand -tinted miniature reproduction of bote seat. good for and what it will do for me, etc., etc.... of knowledge. But it is so un- Tike advantage now of this amazing offer end send your photo today but rather, use Konzentrator piously, meekly necessary now! This great UNITED PORTRAIT COMPANY with humble expectancy. Allow the psychic 1652 Ogden Avs.,Dept. 683 Chicanos 116 power of the instrument to act independently, Question and Answer Book, electonically. (No such word.-EDITOR.) If you do this twice daily you will soon be transformed compiled by the staff of Radio into a mental giant. Use the Konzentrator for News, probes into Radio and the first time immediately before retiring (sleep will be refreshing and recreative), then in the its problems from every angle- morning immediately upon awakening preparing gives have yourself for the day's work. As soon as knotty and answers that the Choose ANY problems tax your mental power put on the sweet tingle of money saved. Konzentrator and seek inspiration from it and $20 Musical Instrument not be disappointed. Thoughts come to Circuits, Amplification, Bal- Yea,wo wí11 give you free a $20.00 qual!ty V iolin,TenorBanio, you will Hawaiian Guitar. Banjo, Banjo -Guitar, Cornet, Goiter, you in logical order. Empty-headedness is a ancing, Regeneration, Trans- or rand1in. Learn e thing of the past. teach mmen Bawomen, boy Amaaziyngnnew, elm- sbyy meall. Lessons. KONZENTRATOR will help you in your home mission, Set Construction, Oper- mentfulphó and fisi ssonneston FREE TRIAL. er 600,000 am. To follow a correspondence course be- cupils.i Write today. No obligation. studies. ation, Speaker Design, Control, CHICAGO CORRESPONDENCE SCHOOL OF MUSIC INC. comes infinitely interesting instead of wearisome. 1632 No. Halsted St. Dept. 55-4 Chicago, Ill. High School and College Students who cannot Electrification, Accessory In- stick to their work are strongly recommended to use the KONZENTRATOR; in short every man stallation, Antenna Possibilities You and every woman, whatever their calling, should not a thing about can possess this wonderful psycho -technical instru- -there's earn mon- ment and use it diligently. Radio that it misses. ey and Do not loan or allow your KONZENTRATOR BOYS to be worn by any other person. The apparatus 1001 RADIO QUESTIONS win prizes in your spare time. will adjust itself to your peculiar body heat and to your own personal psychic nature and nerve AND ANSWERS Write Me Today centers. C'T'I Pu Co. information will follow. Jim Thayer, Dept. 54, Id,hing Further 50c at all newsstands or direct In a separate postal card, sent to a "sucker" list, the following interesting state- EXPERIMENTER PUB. CO., INC. HandiellWtorTkooslla inp Your are made by the iJovom Chemical LE PAGE'S ments 230 Fifth Avenue New York, N. Y. Company : I GLUE In bottles. tubes and cans (Continued on next page) Science and Invention for March, 1928 1061

THOUGHT KONZENTRATOR-LATEST SWINDLE (Continued from page 1060)

September Discount to Educators 20'7.'0. airedale could perhaps not have allowed his Use new psycho-electro-physiolochical ac- the the infinite ! cessory KONZENTRATOR and note how you are soul to float away toward able to concentrate your thoughts and how new, original ideas flow into and Loin your mind, it may, the test of the Kon- whether writing business or private letters, legal BE that as brief, music, a sermon, a speech, facts or fiction. zentrator, on which we concentrated It opens the mind to inspiration; it recharges our for almost a week, proved a grand flop. depleted neurones, the bi -polar nerve -cells of the other stunts with the brain. Every EDUCATOR, thinker, professor, We would have tried teacher, student, lawyer, musician, preacher, Konzentrator, because the Novom Chemical housewife, housemaid; also all mentally and Company told us that further information physically backward school children, should use but such did not prove the the KONZENTRATOR; all need more and better would follow, brains. All study, and even memory training are case, so we reluctantly had to abandon our FUTILE if the mind is in the least degree un- investigation. INSTANTLY receptive, unretentive or morbid. of this You can now start any cold motor without trou- KONZENTRATOR is efficient and quite harm- Seriously speaking, the cleverness ble and do it in a few seconds, through the use of a less. It weighs and is worn like, and is to the latest swindle is, that here we have a con- marvelous new device which puts power into the cylinders. Not a gas, not a special liquid. Works mind, what spectacles arc to the eyes. glomeration of meaningless articles, which results. None sent on approval. Shipped by first-class thinking, and im- from the Dash. Just a touch gets mail in elegant pocket rase anywhere in the are supposed to stimulate U. S. A., prepaid, for ?10.00 P. 0. Money Order. prove thinking. It is supposed, according This Amazing Invention Is simple, but utilizes a well known scientific principle NOVOM CHEMICAL CO. to the German booklet, to refreshen you which gives marvelous results in cold weather starting, mentally. In two weeks, you are supposed It fits any car. It fits any engine and can be installed In BUT this literature is really quite harm- to lose all nervousness, if you only wear the just a few minutes. The cost Agents' Offer is so small that anybody can Any go-getter who less when you compare it to what the Konzentrator; it helps your health, and, ac- afford It. wants to make a lot of you must learn how money, who wants to Germans are putting out. They are actu- cording to the booklet, be independent of a ally publishing books and booklets about to "think plasticly"-whatever that means. Winter Driving mere job and who can It's now a pleasure to drive sell a "good thing" this new wonder, the Konzentrator, and it Not only that, but it is supposed to make in cold weather. Let your car should write quick for stand wherever you want to. offer of too ! The Konzentrator our special to live would take about half of the text pages you a clairvoyant, Don't worry about its getting agents. Send for in - he cold. Step on the starter and now SCIENCE AND INVENTION to quote all of the is advertised to an accumulator and collec- away you go. Or a turn of the formation about results. bíg discounts and cabalistic properties of the Kon- tor of mental energy. crank gets equally good be - wonderful Use your car in cold weather. special proposition, zentrator. The Konzentrator, by the way, It's fun driving when equipped fore the best territory la all taken tu t is manufactured by a German concern in with this marvelous device. Wurtembuerg, the full name being Baum - Satisfaction Verlag, City of Pfullingen. It is interest- Absolutely GUARANTEED firm publishes a num- Yes, we guarantee every Impelerator to do exactly ing to note that this what we claim for it. We guarantee it to make cold ber of mystic books of a non-scientific weather starting easy and we back our guarantee with a great money back offer. Try the Impelerator for one character. day, five days, ten days if you want to. In the worst kind of weather, and then if you are not more than satisfied, send it back to us and every penny will be returned WHEN we first received the Konzen- to you without question or argument. You can't lose and you can have all the summer advantages of driving la trator, we of course submitted it to the coldest weather. Write today. all of the tests given. We dampened both with a little water, breathed Send No Money of our temples Don't send a cent, but write quick for full particulars several times upon the center capsule con- which tell you bow you can get this marvelous device at a special low price. Remember its cost is so little that taining the famous concentration chemicals, anybody can afford it. Even on the cheapest ear. It is to say, our breath did not changt handsome in design and an ornament to the Dash. Do but, strange not hesitate, the capsule into a battery. None of the tes' but write right now. we made proved that anything went on what- The Impelerator Corporation, Dept.2638 soever. When our body heat (as per in- 25 East Jackson Blvd., Chicago, Ill. structions) had warmed up the Konzentra- Please send me hill particulars free, and without our- obligat Ion, of your marvelous invention, the Impelerator, tor, we retired to a quiet place, seated and tell me how I can get one for my car. selves comfortably, relaxed from head to If you are interested in the Agents' Offer, foot, and thought practically of nothing. But Check Here our soul had not been induced to flgat away Name towards the infinite, and it absolutely refused Address to vibrate into the Harmonious Cosmos, as per directions. We wore the apparatus for K®N71IENTlRAú®R City State ten minutes, and had a number of people who knew nothing about it wear it also; but after the test, they all wanted to know what Type of illustration used in the Konzentrator the joke was, because nothing was changed advertising. in their bodies, nor in the souls of the wearer. PARKS It did, however, have some effect. Some of Lack of space forbids us to quote all of WOODWORKING MACHINES the subjects got quite angry for taking up the rest of the bunk that the Konzentrator Cabinet their time with this hokus-pokus, and we is supposed to effect, yet, this fake is not Shop are not certain that the Konzentrator thus as bad as some of the other American ones, Special cure affected their souls and their "Harmonious because, at least, it is not supposed to No. 10 Cosmos." all sorts of diseases, and in this way is only a harmless swindle ; if it does you no good, WE then submitted the Konzentrator it can do you no harm. It is a sort of difference $290 to a number of laboratory tests; elec- glorified rabbit's -foot, with the tric, magnetic, chemical, as well as radio that you are paying $10.00 for it. It is, in with Motor all respects, just as efficacious as the rab- You ought to have this test, much to the amusement of the labora- handy Parks in your shop. assistants. There was, however, no bit's -foot or an elk's tooth, carried as good Compact, eompletemaclihie tory designed like a big produc- indication that the Konzentrator had the luck talismen. tion outfit at one -fifth the cost. Fits in a corner of your slightest effect on anything. Thinking, per- Oh, yes, come to think of it. It did stimu- basement. Does any kind of cabinet and joinery work. late our thoughts to one extent, at least. Write for circular haps, that our flagrant disbelief had some THE PARKS WOODWORKING MACHINE CO. misunderstood Kon- We wondered what we paid the $10.00 for. 1553 Knowlton Street, Cincinnati, Ohio mystic effect upon the Canadian Factory: 20s Votre Dame East, Montreal zentrator, we next tried it on an airedale The device is clever, because it is a jum- for ten minutes. The airedale was resting, bled, nonsensical conglomeration of metal, while the test leather, cork and gelatine. It has a mystic AROUND THE WORLD WITH and was dozing comfortably not went on. If he had a Harmonious Cosmos, appearance. Yet the makers are careful THE INTERNATIONAL CLUB the supposed action of the concen- the test did not reveal it, because the dog to state letters, magazines, form Interesting and are very silent about it, be- Exchange post cards. never moved; and when the test was over, trator. They educational friendships with members in Old Mexico, Spain. Cuba. of course, that there is no he merely blinked his eyes at us, the same cause they know, Porto Rico, Central and South America. Language students. place within the Kon- as he always does when he wakes up. Of action at all taking travelers, educated young people everywhere. send 10 cents in course, the test may not have been fair to zentrator. stamps for booklet and full particulars. A harmless swindle, but a fake, neverthe- the Konzentrator, because a dog is not sup- INTERNATIONAL CLUB. BOX 670. HAVANA. CUBA posed to have a soul, and consequently the less ; all the way through. Science and Invention for March, 1928

Opportunity Ad -lets YOU will find many remarkable opportunities and real bargains in these columns. It will pay you to read and investigate the offerings made every month by reliable firms, dealers and amateurs from all over the country. No matter what you may be seeking, whether supplies, automobile accessories, the opportunity to make money, or anything else, you will find listed here the best and most attractive specials of the month. Advertisements in this section twelve cents a word for each insertion. Name and address must be included at the above rate. Cash should accompany all classified advertisements unless placed by an accredited advertising agency. No advertisement for less than 10 words accepted. Ten per cent discount for 6 issues, 20 per cent discount for 12 issues. Objectionable or misleading advertisements not accepted. Adver- tisements for the May issue must reach us not later than March 5th. EXPERIMENTER PUBLISHING CO., INC., 230 Fifth Avenue, New York, N. Y.

Advertising Agencies Airplanes, Aviation (Continued) Correspondence Courses

24 wards -355 Rural Weeklies $14.20. Ad -Meyer, Model Airplane Engines: t,ü h. p. in 3 lbs.; 1 h. p. in Used correspondence school courses sold on repurchase 4112 -SI Hartford, St. Louis, 1110. 5 1hs. Stationary Engines: 1/2 h, p. in 10 lbs.; 1 h. p. in basis. Also rented and exchanged. Money -back guarantee. 15 lbs. Circulars free. DYNAMIC MFG. CO., First Nat'l Catalog free. (Courses bought). Lee Mountain, Pisgah, Bank Bldg., Chicago. Alabams. Agents Wanted Boys -12 Inch Cross -Atlantic Model, "Lindy" type Airplane -50c. Takes off by own power. Travels over 40 Agents: Newest sensation-Rhinestone Initial Fountain feet. Very fascinating and educational. Thrilling fun! Detectives Pena. Everybody wants one. No competition. $8.00- Easy construction set, complete materials; postpaid U. S. $15.00 daily in advance. Chaton Novelty Co., 602 Blue 50c. (No stamps.) Satisfaction guaranteed or money Detectives Earn Big Money. Travel. Excellent oppor- Island, Chicago. refunded. Model Aircraft Co.. Box 331, Chillicothe, Ohio. tunity. Slake secret investigations. Great demand everywhere. Experience unnecessary. Write American Detective System, MIRRORS RESILVERED AT HOME. COST LESS 5 Send dime for 12 -inch mounted propeller and circular 2190 Broadway, N. Y. cents per square foot; You charge 75 cents. Immense on free three-foot model aeroplane. No selling. Aero profits. Plating autoparta, reflectora, tableware, stoves. Shop, 3050 Hurlbut Ave., Detroit, Mich. Refinishing metalware, etc. Outfits furnished. Details FREE. Write SPRINKLE, Plater, 955, Marion, Indiana. Drawing Why work for ethers? Employ agents yourself. Make Battle Photos and War Relics Amateurs!. Draw Cartoons for Magazines. Newspapers. your own Products. Toilet Articles, Household Specialties, Stamp brings particulars. Western Service, S. 1224 N. etc. 500% profit. Valuable booklet free. National Artesian, Chicago. Scientific Laboratories, 5975W Broad, Richmond, Va. For Dens: Relics from Europe's battlefields (also medals) illustrated catalogue with sample war photos 25c. Interna- $50.00 Weekly easy, applying Gold Initials on Automo- tional, 885 Flatbush Ave., Brooklyn, N. Y. biles. No experience needed. $1.45 profit every $1.50 Electricity lob. Free Samples. "Rake Monograms," R1043, Wash- ington, Boston, Mass. Books Electric Fun! Seventy stunts, 110 volts, $1. Cuttingco, Gold Leaf Window Letters & Script Signs. No ex- Campbell, Calif. free. Consolidated, 69 -R - perience; 50% Profit. Samples Free-My illustrated Circulars on Newthought, Selfcul- West Van Buren, Chicago. tare. Healing, Yogi Philosophy, Occult, Mystic and Scien- New Invention -400% profit. Liquid quick mend for tific Books. Martens Publisher, Inc., Burlington, Iowa. For Inventors Fabrica and Hosiery. Stops runs. Every woman buys. Hundred other fast sellers. J. E. Johnson Co., Dept. 863, Inventions Commercialized. Patented or Unpatented. 6129 Wentworth Ave., Chicago. Business Opportunities Write Adam Fisher Mfg. Co., 205 Enright, St. Louis, Mo. day representing big Harley factory. Established 35 $12 Unpatented Ideas Can Be Sold. I tell you how help years. Sell friends, neighbors-daily necessities that re- $100 per month in your home, folding and mailing and peat-groceries, extracts, medicines, etc. Steady, profitable you make the sale. Free particulars (Copyrighted). Write circular, We furnish everything. Particulars and samples W. T. Greene, 808 Jenifer Bldg., Washington, repeat bustnese. $3.00 hour part time. Samples furnished. 25c. Adams Mailing Service, Box 236, Belwood, Pa. D. C. Harley Company, Desk C-2524, Dayton, Ohio. Patents Obtained under cooperative payment plan. Write Agents Wanted to sell Men's Hats direct from factory. Sell Komic Kards in spare tine. Dime brings samples, for particulars. W. E. Beck, Registered Patent Lawyer. Write for catalog. Model Hat Mfg. Co., Dept. M-11, information. Robert Fleming, 331 Wooden St., Pawtucket, 953 Jenifer Bldg., Washington, D. C. East Orange, N. J. lt. I. lamps, Inventors. Use our special service for presenting your $10 daily silvering mirrors, plating and refinishing $50.00 for one Photograph! ! 1 Earn extra money, spare new method. Outfits invention or patent to manufacturers. Adam Fisher Mfg. reflectors, autos, beds, chandeliers by time with a camera. Experience unnecessary. Address, Co., 205-A Enright, St. Louis, Mo. furnished. Write Gunmetal Co., Ave. D, Decatur, Ill. REDKItAFTS, Dept. 9, Denver, Colorado. or outfits. $25.00 cash prize each month awarded to inventors of Big money easily made without peddling By large Free particulars. E Elite, 38E Elizabeth St., N. Y. Sell Mail!-Books, novelties, bargains; profits! unpatented inventions, with right to publish. Send draw- Particulars FREE! E -Elfes, 525 South Dearborn, Chicago. ing or photograph with description. Dynamic Mfg. Co.. Agents-We start you in business and help you succeed. First Nat'l Bank Bldg., Chicago. No capital or experience needed. Spare or full time. You Print 250 Signs or Pictures an hour without press, type can earn $50-$100 weekly. Write Madison Company, or machinery. Sample and particulars 10c. Straco, Take Care of Your Ideas, and they may some day take 566 Broadway, New York. 1015%. Springfield, Ohio. rare of you. Thru "IDEAS" Incorporated, Lancaster, Pa. Patents, United States and Foreign, Searches. Rummage sales make $500.00 monthly. We start you, Free Book. Start little Hall Order business, Hadwil, furnishing everything. Experience unnecessary. Monarch, 5A-74 Cortlandt Street. N. Y. Desk 4, 609 Division, Chicago. Formulas Just Out-New Patented Apron. No strings or straps- Amateur Cartoonists: Make money in apare time with new cartoon selling plan. Write Smith's Service, Wen- $20.00 a day every day; over 100% profit; commissions 500 Formulas and Big Catalog 20c. Ideal Book Shop daily. Write for free offer. Sta -Put Co., Dept. 503, atchee, Wash. (N), Park Ridge, III. St. Louis, Mo. 24 Money Making Plans, 25c (coin). Soffron, 780 We Start You-Silvering mirrors; plating tableware, Hazelwood Ave., Pittsburgh, Pa. autoparts, headlights, etc.; refinishing metalware, chan- Health deliers, bedsteads, etc. Immense profits. Outfits furnished. WESCO. B-1246, D, Wichita, Kans. Cameras and Photography Supplies Tobacco or Snuff habit cured or no pay. $1.50 if men Sent on trial. Willard Company, Box 796, Los We Start You in Business, furnishing everything; Amired.ngeles, Calif. and women, $35.01) to $100.00 weekly operating our "New Few dollars start you Make money in Photography. Learn quickly at home. System Specialty Candy Factories." Spare or full time. New Nothing like it. Ex- home or small room anywhere. Booklet free. W. HILL- plan. 1.29, Orange, N. J. perience unnecessary. American Sehpol of Photography. YER RAGSDALE., Drawer East Dept. 5333, 3601 Michigan Avenue, Chicago. Help and Instruction Agents-Best seller; Jem Rubber Repair for tires and of over 800 per Men-Women, 18 up. Get U. S. Government Life Jobs. tubes; supersedes vulcanization at a saving $1140 to $3300 year. Steady work. Many Railway Mail cent; put it on cold. It vulcanizes itself in two minutes Chemistry Clerks-Clerks-Carriers. appointed every year. Inside and is guaranteed to last the life of the tire or tube; sells and Outside Work. Experience unnecessary. Common to every auto owner and accessory dealer. For particulars education sufficient without coaching. List positions and bow to make big money and free sample, address Amazon Learn Chemistry at Home. Dr. T. O'Conor Sloane, Our full particulars-FREE. Write today sure. Franklin Rubber Co., Philadelphia, Pa., Dept. 601. noted educator and scientific authority, will teach you. Institute, Dept. A4, Rochester, N. Y. home study correspondence course fits you to take a posi- $60-$200 a week. Genuine Gold Letters for store win- tion as chemist. See our ad on page 975 of this issue. dows. Easily applied. Free samples. Liberal offer to Chemical Institute of New York, 16 E. 30th St., New Work for "Uncle Sam." Life Jobs. Steady work. Metallic Letter Co., 441 B., North Clark, York City. 995.00-6275.00 month, Men -women, 18-50. Thousands 1928 general agents. appointments. Common education sufficient with our Chicago. coaching. Experience unnecessary. List positions and full buys gold ini- "Dope Sheet for Chemical Experimenters" 25c. "101 Write today sure. Franklin Institute, Big money and fast sales. Every owner EXPERIMENTS" 25e. Good stuff. Both particulars-FREE. tials for his auto. You charge $1.50; make $1.35. Ten CHEMICAL, Dept. A16, Rochester, N. Y. free samples, just published. A. Walker Co., 1514 Allison, Washing- orders daily easy. Write for particulars and ton, C. American Monogram Co., Dept, 71, East Orange, N. J. D. Succeed With Your Own Products. Make them yourself. Your Chemical problems solved and working process fur- Help Wanted Formulas, Processes, Trade -Secrets. All lines. Catalog, nished for Five Dollars. Write me. W. Stedman Rich- free. D. Thaxly Co.. Washington, D. C. ards, Consulting Chemist, Box 2402, Boston, Mass. Men-Experience unnecessary; travel; make secret in- Circulars vestigations; reports; salaries; expenses. Write American Agents: Big season on. No competition. $10.00- Practical Chemistry, a 5x8, 12-20 page, chemistry Foreign Detective Institute, 304, St. Louis, Mo. $15.00 daily. Rhinestone Initial Buckles, etc., sell on magazine. See it for 10e. Practical Chemistry, Lake sight. No investment. Chaton Co., 600 Blue Island, Andes, S. flak. Silvering Mirrors. French plate. Easily learned, im- Chicago. mense profits. Plans free. Wear Mirror Works, 16 W. Attention Chemical Experimenters! 100 Chemicals con- Excelsior Springs, Mn. sisting of complete selection for the experimenters' Labor- Aviation atory. Put up in wooden box In a manner easily access- Distributors-No canvassing; no capital. Honery, Roseta. Airplanes, ible. Sufficient quantities for hundreds of experiments. Pa. $7.00. 50 Chemicals, 12 pieces apparatus. Really a won- Biggest, Best Catalog Model Airplanes. Parts, Supplies; derful outfit for experimenter's laboratory. Sufficient for 1691/2 Spring Street, New 5e postpaid. Ideal Company. many experiments. $5.00. Postpaid U. S. A. - Send How to Entertain York. money order or C. O. D. to Pines Chemical Company, Ave., Brooklyn, N. Y. Airplanes-Send for free cuts and Plane of our wonder- 1524 St. Marks Plays, Musical Comedies and revues, minstrel music, ful two Place. Companion type, small, high life wing blackface skits, vaudeville acts, monologs, dialogs, recita- and New "Amateur Chemist" magazine. Everything for tions, entertainments, musical readings, stage handbooks, monoplane, and information. How to build this ship, -Allen Lab., 910 W. be sure it will fly. also Propeller literature. Crawford chemist. Only 10e copy. Thompson make-up goods. Rig catalog free. T. S. Denison & Co.. Aimlane Manfgr., Seal Beach. Calif. Pine. Shamokin, Pa. 623 So. Wabash, Dept. 99. Chicago. Science and Invention for March, 1928 106.3

Insects Wanted Patent Attorneys Printing Outfits and Supplies

own etc. See Sinclair's Adver- Patents: butch valuable information in our illustrated Print your cards, stationery, circulars, paper, Cash paid for butterflies, insects. Complete outfits $8.85; Job Presses $11, $29; Rotary ti-entent on page 1053. book on patents and, trademarks sent free with sketch sheet. Send your invention for inspection and opinion. $149. Print for others, big profit. All easy, rules sent. Write today. Bryant & Lowry, 314-A Victor Bldg., Wash- Write for catalog presses, type, paper, etc. Kelsey Com- D. C. pany, l'-6 Meriden, Conn. Instruction ington, Patents. Booklet free, Highest references. Best re- Watson E. Coleman, Patent T. O'Conor Sloane, sults. Promptness assured. Printing, Engraving and Multigraphing Learn Chemistry at Homo. Dr. D. C. noted educator and scientific authority, will teach you. Our Attorney, Washington, hume study correspondence course fits you to taise a position as chemist. See our ad on page 975 of this issue. Chemi- Patetfts Sectced. Easy terms. Inventors Service Bureau, 200 Letterheads and 100 Envelopes, $1.10, postpaid. cal Institute of New York, 16 E. loth St., New York City. Boa 1643, Washington. Oberman Company, Pox 1268, Chicago. Patent Lawyer, Washington Loan no Richard E. Babcock, Mirror Silvering, complete instructions and formula, & Trust Bldg., Washington, D. C., Booklet. outfit necessary. Twenty-five cents. J. Comiskey, 345- Radio Sih St., Ann Arbor, Michigan. Monroe E. Miller, Ouray Bldg., Washington, D. C. Patent Lawyer, Mechanical, Electrical Expert. Booklet. Be the licensed Radio Doctor of your community. 37- and y Record blank gratis. Make Your Own Banjo. Educational and instructive Prioril $10 spare time evenings. Secure franchised territory now. little bosh sells all. l'rice $1.00. J. Comiskey, 345 Write for free booklet. Co -Operative Radio Doctors Dept. 8th Street, Ann Arbor, Mich. Patents-Send for form "Evidence of Conception" to be 11, 131 Esc..,ex St., Salem, Mass. signed and witnessed. farm, fee schedule information free. Lancaster and Allwine. Registered Patent Attorneys in Men Wanted who can drive rar, to qualify for U. S. I 'sited States and Canada, 212 Ouray Bldg., Washington, Bulb B Eliminators. 4 taps, forty milliamperes, Silent. Government Chauffeur -Carrier (truck driver) jnbs; $141- D. C. Steel case, bronze finish, complete. $0.50 -2 -Ampere Stilt $175 month. Write Instruction Buroso, Dept. 293, Arcade chargers, $9.00. Sent C.O.D. Catalog, Elcetrs-Chemical l;ldg., St. Louis, Mu. Unpatented Ideas Can Be Sold. I tell you how and help Company of America, Indianapolis. you make the sale. Free part is utars. (Copyrighted n. Write W. T. Greene, 809 Jenifer Bldg., Washington, I). C. Set Builders. We furnish jobs. No fee. Register now Inventions Wanted Patents. Time counts in applying for patents. Don't on our list of professional set builders. Inquiries from risk delay in protecting your ideas. Send sketch or model your locality will be referred to you. We are headquarters for instructions or write for Free book. "How to Obtain a for parts of Hanunarlund-Roberts, Silver Shielded Six, Equamatic, Bremer -Tully Power Six, Harkness Inventions Commercialized. Patented or Unpatented. and ' Record of Invention" form. No charge for Karos Patent" Register at once. Write Adan Fisher Mfg. Co., 205 Enright, St. Louis, 51o. information ors hose to proceed. Communications strictly Couuterfunic and other popular circuits. confidential. Prompt, careful, efficient service. Clarence A. Give references and experience. Allen -Rogers -Madison, O'Brien, Registered Patent Attorney, Security Bank Inc., Dept. RN, 35 West 31st Street, New York, N. Y. Will buy approved invention. Write W. L. Kendig, 416 Building (direct ly across street irons patent office), Wash- N. Duke Street, Lancaster, Pa. ington, D. C. See page 1035. "Inventor's Advisor," V-aluahle Patentbook sent free. Radio Equipment Machinery and Tools Labiner, 3 Park Row, New Torir. Tremendous Sav- lve Payment Plan. Direct Factory Sale. Wholesale prices. Patents obtained under Co-oterat Selling direct to Here are some of our sunny and Catalog particulars. W. E. Beck, Registered Patent ings. you. Concrete Building Block btachines folds. Write for items: 30 Henry Choke, 100 M.A. $2.19; 10 Henry Choke, 5 St., St. Louis, Sto. 952 Jeniter Bldg., Washington, 1). C. free. Concrete Machine Co., N. First Lawyer, 100 M.A. $5.43. Power Transformers for all kinds of Eliminators and for all types of A.C. Tubes at Special Low Get your own patents. Forms, complete instructions $1. Prices. EVERY ITEM l'C'I,LY GUARANTEED. Prompt- Cutthtgbros., Campbell, Calif. ly shipped upon receipt of order. Send for free Illustrated Magic and Games catalog today. Todd Electric Co. Inc., (Manufacturers ), ADAM E. FISHER, Registered Patent Attorney, in 36 West 20t1 Street, Dept. B, New York City. Free with $25 order our large die box. Send 20c for business 25 years; references; personal attention and our large catalogue of tricks. puzzles, wigs, sensational promptness assured; Dept. E. 205 Enright, St. Louis, Sto, escapes. Oaks Magical Co., Dept. 519, O,hlao>h, AV'id. Patents. Free advice, personal service of registered At- Salesmen Wanted torney, former Patent Office Examiner. Booklet, Albert Jacobs, 723 Barrister Bldg., Washington. Magical Goods Punchboard Salesmen. $1511 weekly, selling new double he'ed cer- profit deals front catalog. 100;ó prospects. 911% sakes. Inventors who derive largest profits know and Sales. Magic --For something new and different, send 1Oc for tain simple but vital facts before applying for Patents. Exclusive territory. Repeat commissions. Rudy large magical catalogue. Sterling Magic Co., I1ox 33, Our book Patted Sense gives those facts; free. Lacey & 1652 Division, Chicago. Danville, Va. Lacey, 644 1' St., Washington, D. C. Established 1869. of character. Reliable services by A Paying Position Open to representative Patent, Trade -Marks, Copyrights, direct to wearer. Good in- an experienced practitioner devoting personal attention to Take orders shoes-hosiery Male Help Wanted P. come. l'ermanent. ACri to now for free book. "Getting each case. Inquiries invited. Reference furnished. It. Boston, Moss. Fishburne, Patent Lawyer, 525-D McGill Building, Wash- Ahead." Tanners Shoe 311g. Co., 0603 C St., Men, get Forest Ranger lob; $125-$200 month and home ington, D. C. furnished ; hunt, fi -.h, trap. Fur details, Write Norton, 265 Temple Court, Denser, Colo. Punchboard Salesmen. 2 hours daily. $10(1 every week. Patents-Wei se for Instruct tons. Carl Miller, Registered commission on repeat busi- Pat ont Office Examiner), 211-B New line. Lowest prices. full Patent Attorney (former ness. Catalog Free. Puritan Novelty Co., 1409 Jackson. Firemen, Brakemen, Baggagemen (white or colored), SleG1 il Building, Washington, D. C. sleeping car, train porters (colores), $150-$250 monthly. Chicago. Experience unnecessary. 897 Railway Bureau, East St. at home, spare time, writing short Louis, IH. Make $25 Weekly stories for phut oplays. Experience umnece:aary. Outline Salesmen wanted to sell guaranteed hen)] forged tools free. Producer, league, 1t113, St. Louis, Mo. to garage. Fly ink Tool & Forge Co., Inc., Grafton, Wisconsin, Miscellaneous Patents Procured; Trade 31 arks Registered-A comprehensive experienced, prompt service for the protection Beautiful Registered Bull Pups, 915. Bulldogs, 501 and development of your ideas. Preliminary advice gladly Rockwood, Dallas, Texas. furnished without charge. Booklet of information and Song Poems form for disclosing Idea free on request. Irving L. 41-T All angles and sides. Trigonometry; McCalhran, 202 Owen Bldg., Washington, D. C., or Angle Calculator.. l':u4c Row, New York. Free-"Song Poem \Vriters :Manua l." Sequoia Song - not needed. Fraction Table. Add. subtract. Automatically I,ns ,Aueeles, Calif. reduces lowest term. $1.00 Each. Both for $1.50. G. riters Service. Sherman Irranch, O. Matter, L'oard of Trade Bldg., Portland, Oregon. Descriptive prices Patents Song -poem writers. Address \lu,arrh. -., i \Vest 55th, "Yew Bows" ---$10 to 925-Delivered. New York. mi request. Olympic Yew Archery Co., Port Angeles. Dept. 133, Was)]. Inventions Commercialized. Patented or l'npatent ed. Write Adam Fisher \I fg. Co., 205 Enright, St. Lonis, 31o, for propesit ten. Ray Hib- Metal Song Poem Writers-Send Manufacturing- Well Equipped Factoy wants heler, 1)24, 21rí1 N. leystone Ave., Chicago. Articles to Manufacture. Vi'e also Develope-Inventions, bl alto Dies, Manufacturing Equipment. Sheldon Mtg. Co., Box 5055, Gateway Station, Kansas City. Patents For Sale Song Writers Mexican Made pistol holsters, cartridge belts, horsehair sample by nail. Sanitary Griddle free. Patent for sale, articles, rattlesnake belt. List TEX-MEX greaser. A. Jensen, R6, 886, Stockton, Calif. LEATHER CO., 313 Esperson Bldg., Houston, 'Texas. Free-"Song Writers Guide." Bearer, D21-622 Goodell. Green 11:íy. AVis. Screw Starters, Mechanics and Electricians, you need this new tool. Places screw's in profit bully inaccessible places. Patents Wanted Once you use this tool you sci I1 wonder how you ever gist along without it. Send 25 cents for this wonderful Stain ps and Coins tool. 31177 Novelty Co., 734 Chamber Si., Trenton N. J. Inventions Commercialized. Pat em cd or Unpat ente)]. Write Adam l'i ;her Mfg. ('o., 205 Enright, St. Louis, Mo. Stamps, 100, All D itlerent, 3 cents. S. I. Quaker Stamp Models and Model Supplies Company, 'Toledo, O. Personal 25e.'. Phil Lundsted, Cape ('apst:ins. 1000 Mixed Foreign Stamps Ship Model Fiittings: Steering Wheels. Cotta \mine. Anchors, Propellors. Send dime for booklet. A. J. ge, Fisher, 1002 Etowah Ave., Road Oak, Mich. You: Handwriting Reveals Character. Practical guide to success. Send ink sample of own or friend's writing for l teams. Provi - helpful analysis of surprising facts. 25e (silver). S. Pen - 100 Good Stamps Free to A pprnval 4qi dealer Stamp Co., 1511 Aberson Ave., Provi deuce, R. I. Musical Instruments craft, Cuscob, Connecticut. Movie Mail. Envelopes with canceller] Stamps atl ached Violins-Deep, Mellow, Soulful-on easy credit terms. nrondnent 11611yweod umvía stars 'csu all of my own make. De- Photography addressed to High grade, wonderful instruments 25 differ:Ist, postpaid for $1.00. - Supply velopment of many years' expertness. Write for hook. over the world; all limited. Edwin T. Vann Wart, Dept. l', F. O. Hog 381, Costae A. Henning, 512 1?niversity Ituil ling, Seattle, somple our big Washington. Have you a Camera? Write for free of Si. O., I,os Angeles, Cal. magazine, showing hose to matte Letter pictures and earn money. American Photography, 118 Cauucru House, Bos- ton, 17, Mass. Old Coins Telegraphy Transfer Photographs to metal. china, etc. Patented A real art. Lets size, 27e; -dollar size, 53e process. Makes beautiful miniatures. Morse and Wireless-taught thor- California Gold, quarter half of Inn and Anyone can do it. Outfit supplied to Telegraphy-Both Columbian nickel and catalogue, 10c. Norman Shultz, Box profit. oughly and quickly. Tremendous demand. Iii g salaries. members oak'. Write about. membership. Kyograph opportunities. Expenses low; chance to earn 716, Salt Lake City, Utah. System, 21-T) W. 17th St., New Yorlt. Wonderful Photo tart. School established fifty years. Catalog free. Dodge's Institute. Stone St., A'a 1paratso, Ind. Old Money Wanted Photo plays Wanted Typewriters $2 to $500 Each paid for hundreds of Old or Odd Coins. money, may be very valuable. Send 10e for $ $ $ For Photopiny Plots, Stories accepted any form, re- Keep all old It all standard makes. $10 up. fully guaran- new illustrated coin value hook 4x6. Guaranteed Prices. vised. criticised, copyrighted, marketed. Estab. 1917. Typewriters, illustrated lists. Company, 14 Booklet free. Universal Scenario Co., 223 Western & teed. Free trial. Write for complete Get Pasted, we pay ('ash. Clarke Coin 121 N. Franc isso Aso., Chicago. Street, Leltoy, N. Y. Santa Monica Bldg., Hollywood, Calif. Northwestern Exchange, 1064 Science and Invention for March, 1928 ONLYQLEIGH FOR BRI [LIANT NOVELS in Book Form

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