SCIENCE-ADVERTISEMENTS

HECTOR, LEIN & SCOUTENElectronic PhysicsWritten for beginners, this text gives a clear, well integrated study of the 289 Illus.fundamentals of electricity and light by means of modern electronic con- 355 Pagescepts. The illustrations are in colors. By L. GRANT HECTOR, H. S. LEIN $3.75and C. E. SCOUTEN.

FOLEYCollege Physics-3rd EditionFor students of liberal arts and science, this text contains those elements 470 Illus.which make for a quicker and clearer understanding of beginning college 757 Pagesphysics. It is widely adopted. By ARTHUR L. FOLEY. $3.75

DUFF (And Contributors)Physics-8th EditionWell liked by students and teachers, this text offers a stimulating study of 630 Illus.-physics as required by students of engineering and the sciences. Written 715 Pagesby collaboration of eminent physics teachers. Edited by A. WILMER DUFF. $4.00

STRANATHANThe "Particles" of Modern PhysicsBuilt around the "particles" of modern physics, the electron, positive rays, 218 Illus.photons, positrons, neutrons, mesotrons, X-rays, alpha, beta and gamma 571 Pagesrays, and cosmic rays, this text presents the essential fundamental con- $4.00cepts. Experimental foundation for each concept is stressed. By J. D.STRANATHAN.

SURVEY COURSESMcCORKLESurvey of Physical Science for College StudentsThis text is designed as a survey or orientation course in the physical sciences 273 Illus.giving the background required by the teacher in general science and by the 471 Pagesliberal arts or cultural course student. Experimental exercises are included. $2.75By PAUL MCCORKLE.

CULVERMusical AcousticsFor students majoring in music and those interested in a modern study of 128 Illus.the physical basis of music, this book offers a well balanced and thoroughly 194 Pagesinteresting study of the subject.. By C. A. CULvER. $2.50

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AUGUST 25, 1944 9

SCIENCE-SUPPLEMENT VOL. 100, No. 2591

SCIENCE NEWSSience Service, Washington, D. C.

ToH USE OF RADIO FOR RAILROAD COM-MUNICATION AND SIGNALING

A NEW application of radio to increase efficiency, speedoperations and insure safety on railroads will be the sub-ject of hearings before a committee of the Federal Com-munications Commission to begin in- Washington on

September 13. Interest in the use of radio by railroadshas reached an all-time peak, as witnessed by the factthat over 37 applications for two-way radio equipmentdevelopment have been filed with the FCC, since January.Some permits have already been granted.

These hearings are for the purpose of developinginformation which may be of assistance and guidance toall parties in carrying out their further programs on theuse of radio on railroads. Although no immediate de-termination of policy is contemplated, the present investi-gations may herald a new era of railroad safety, ac-

cording to an interview with James Fly, chairman ofthe Federal Communications Commission, as follows:"The applications now pending before the FCC cover

two-way radio communications between the dispatcherand trains in motion, between trains, and between thehead-end and rear-end of each train. The use of 'walkie-talkie' for flagmen and brakemen is also contemplated."All these services involve two-way radio communica-

tion as distinguished from carrier-current systems whichtransmit through the rails or other metallic circuits ad-jacent to the tracks, using low frequencies."The fact that to-day radio traffic control methods are

used in directing the movement of railroad cars carryinghigh explosives is proof of the safety of the method. Ithas been stated that an engineer in a radio-equippedengine can do in three minutes with radio what he wouldotherwise take 15 to 20 minutes to do. Radio may beof great help in bottleneck freight yards where you now

have to depend on flag, lantern or messenger signals.Operation would be more efficient because the engineercan acknowledge receipt of information and ask questions.In the event of derailment or other emergency, traincrewmen would be able to carry on two-way communica-tion with the nearest control point."It is possible that many terrible railroad accidents

could have been averted if radio equipment had beenavailable."Radio if put into regular use on trains will supple-

ment existing telephone and telegraph equipment, ratherthan replace it. Although radio was tried out experi-mentally first by the New York Central Railroad as earlyas 1925, the railroads have not been as quick to takeadvantage of radio as the maritime world and the avia-tion industry."The FCC is very sympathetic regarding the need of

radio for safety purposes by the railroads, and standsready to grant applications as long as the operation re-

quested will not interfere with other communications.At the same time we feel that the initiative should come

from the railroads, and to avoid crowding of the channels

it may be that the railroads will have to work out some

joint communications system."Use of radio in lieu of standard broadcast for rail-

road communications is a possibility. FM will not beaffected by high interference levels in Diesel-electriclocomotives, and in addition to operation in railroadyards, it can operate for intra- and inter-train communi-cations on main lines. Practicable means may be foundto use radar in the future to warn engineers of theapproach of another train. With radar an engineer willbe able to 'see' a train on the track ahead at a longdistance."Chairman Fly predicted that radio might some day be

used to break the present wall of isolation between railtravelers and the outside world. He suggested thatradio could provide two-way telephone communicationfrom moving trains, and that radio and television couldgive travelers entertainment, thus combining a safer andspeedier trip with all the comforts of a modern home.-ROBERT N. FARR.

ITEMSEUCLID, the great ancient Greek mathematician, who

lived 2,200 years ago, presented a classical problem thathe was unable to solve and which remained unsolved untilthe present time. A solution was presented at the Wel-lesley meeting of the American Mathematical Society byDr. Charles N. Moore, professor of mathematics at theUniversity of Cincinnati. The total number of unsolvedtheoretical mathematical problems is now decreased byone. Euclid, Dr. Moore stated, proved that there existan infinite number of primes, that is, numbers such as

two, three, five and seven having no divisors but them-selves and unity. Succeeding generations of mathe-maticians have guessed, but have never been able toprove, that there likewise exist an infinite number ofprime-pairs, that is, successive primes which differ bytwo, such as 11, 13; 17, 19; 41, 43; and so on. At themeeting, Dr. Moore presented an involved but convincingpaper giving his proof of the infinitude of prime-pairs.

1I we can recognize the need for speed in building post-war houses as it was realized in constructing homes forwar workers, we shall have taken the most significant stepin the direction of solving our housing problem, accordingto a report made by Philip M. Klutznick, commissionerof the Federal Public Housing Authority, before a con-

vention in Chicago of the American Home EconomicsAssociation. It was pointed out that we were compelledduring the war to break loose from tradition and use our

imagination. Vastly improved methods of productionand ingenious use of substitutes were brought about bywar housing. No one yet has computed the assets of the

public housing program against actual costs and figuredout that either a community or the nation was the loser.

Each low-rent project has reduced disease, juvenile delin-

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munity.

10

AUGUST 25, 1944 SCIENCE-ADVERTISEMENTS 11

More than 50,000 copiessold since pu icationl

A special edition of 15,000. copies was purchased by the Armed Forces Institute this spring

THE

MACHINERYOF THE BODY

by ANTON J. CARLSON and VICTOR JOHNSON

Enthusiastic comments are still coming from hundreds of teach-ers all over the country.

* "This is the sixth year I have been usingsthis excellent text and expect to con-tinue to use it. I know of no other text in this field that even remotely approachessuch a fine piece of workmanship."-C. P. HICKMAN, De Pauw University.

* "We feel that this book is one of the best in the field, and are glad to hear thatit is finding increased usefulness in schools of nursing, which is as it should be."-HEiLEN G. SCHWARZ, School of Nursing, University of Cincinnati.

* "My decision to re-adopt this text was prompted in part by the repeated state-ments of many students that they preferred it. . . . When a text . . . promptsstudent commendation and otherwise suits the course, it's the one I want to use."-F. H. MCCUTCHEON, North Carolina College of Agriculture and Engineering.

* "I consider this book to be one of the best texts available for the teaching ofhuman physiology."--A. L. HERSHEY, New Mexico State College of Agricultureand Mechanic Arts.

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THE WOODS HOLE MARINE BIOLOGICAL LABORATORYby FRANK R. LILLIE. An Informal history of 56 years ofscientific research at a unique institution. Makes the readerfeel something of the enthusiasm and determination that wentinto its making and its early struggles. Many of America'sfamous biologists pass in review. Illustrated. $4.00

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Published first in 1937, revised in1941, this physiology text still holdsits place as a best-seller among text-books. During 1943-44 schoolsbought 2,000 more than in theprevious year, showing that thisbook continues to meet the needsof teachers and students of physiol-ogy better than other books in thefield.

This NEW PLAN TEXT was usedlast year in the following courses:

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SCIENCE-ADVERTISEMENTS

1844-1944

DANA'S

SYSTEM OF

MINERALOGYVolume I-ELEMENTS, SULFIDES,

-SULFOSALTS, OXIDESRevised by

CHARLES PALACHE,HARRY BERMAN,

CLIFFORD FRONDEL;Harvard University

Volume I

July 19440

Seventh Edition* 6 by 9 * $10.00

DANA is considered indispensable by mineralo-gists, physical chemists, crystallographers, and allthose whose work deals with the study of minerals.The book is known throughout the world, and hasbecome the final authority on the subject of miner-alogy in the hundred years since Wiley first becameassociated with the work in 1844,

This latest edition represents a radical revision,involving a complete change in the book to accom-

modate the new.information that has become avail-able since the previous edition was published. Thevolume of data to be added was so great that thepresent authors found it necessary to rewrite thebook almost entirely. To make the material more

accessible and more convenient to use, DANA hasbeen thoroughly modernized in format.

Of particular interest are these changes found inthis seventh edition: a new mineral classificationbased on crystal chemistry; a new elastic series of

classification numbers for species; new data on

x-ray crystallography; introduction of the treat-ment of species, including generalized formulas fortypes, discussion of group relations, and a sharperdefinition of varieties; revision of specific gravities,based on new observations.

Volume II. Halides, Carbonates, Sulfates, Borates,Phosphates, Arsenates, etc.

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VOL. 100, No. 2591

AUGUST 25, 1944 SCIENCE-ADVERTISEMENTS 13

Storer s

GENERAL ZOOLOGYBy TRACY I. STORER

Professor of Zoology, University of California at DavisMcGraw-Hill Publications in the Zoological Sciences

798 pages, 534x 83/4, 551 figures, 5 colored plates. $3.75-In the past 18 months this immediately successful text has been adopted by 95colleges and universities and has won widespread recognition as an admirablyorganized and unusually teachable treatment of the subject that can unquestion-ably be classed as a standard in its field.

University of AlabamaUniversity of ArizonaUniversity of British ColumbiaBrown UniversityUniversity of CaliforniaUniversity of California at

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Praise for the book:"I sincerely believe that it is the best textbook in generalzoology that I have ever seen.' '-Professor H. W. CUR-RAN, Queen 's University.

"I have explored its pages carefully and can say un-

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"It is a very fine book, in the production of which boththe author and publisher may well be proud of theirachievement. "-Professor- HARoLD KiRBY, University ofCalifornia.

"Professor Storer should be congratulated on his successin setting forth the principles underlying animal biology,

and yet including a comprehensive, systematic survey ofthe animal kingdom within the confines of a singlevolume. "-Professor B. P. YOUNG, Cornell University.

Laboratory Manual for General ZoologyBy TRACY I. STORER. McGraw-Hill Publicationsin the Zoological Sciences. 131 pages, 5% 83/4,$1.25

Designed to accompany Storer 's General Zoology, thisforthcoming manual for the beginning course in zoologycontains a great variety of exercises, resulting in unusualflexibility in outlining a laboratory program.

Suggestions for Laboratory InstructorsBy TRACY I. STORER. (Furnishedgratis to users

of the Laboratory Manual)Offers suggestions regarding laboratory demonstrationsand procedures, to aid the instructor in conducting hisclasses.

Send for copies on approval

McGRAW-HILL BOOK- COMPANY, Inc.

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SCIENCE-ADVERTISEMENTS

VWHEN Fraunhofer in 1814 added a telescope to

Newton's glass prism and Wollaston's light-slit,he was able to locate 576 dark lines crossing thespectrum of the sun. These Fraunhofer lines, as

they are now called, could not be seen by Newtonand were merely noticed by Wollaston.The young experimenter tried prisms of various

transparent materials, and found that the darklines could not be due to the prism itself. Thenhe examined the spectra of the moon and theplanets, and terrestrial objects shining by reflectedsunlight. Since the lines remained in all cases

identical as to number and position, he knew thatthey were not caused by the atmosphere. Whenhe studied the spectra of the stars, however, hesaw that although the colors appeared in thesame order, the dark lines had changed positionand intensity. The character of the light source

itself, then, must somehow be responsible for thelines, and we know now that they are the finger-prints of the atoms.

Fraunhofer invented the diffraction grating,but before he could use it in extending his studyof spectra, he died at the age of 39.

THE PROGRESS OF RESEARCH

Newton to Wollaston to Fraunhofer and theirmany successors- so was research in the scienceof spectroscopy begun and developed.Today, research is kept alive under the care of

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AUGUST 25, 1944 17

18 SCEC-DERIEET Vo 0, 429

. . so that men canfly as high as their planesThe enemy is only one of four adver-

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-indeed, to keep alive and conscious-high-altitude aviators must inhale ox-ygen constantly. Because life itself de-pends upon the cylinders which supplythis oxygen, extreme care must be takenin their design and construction, for inthem the gas is confined at a pressure of400 pounds per square inch.At the Firestone Steel Products Com-

pany, one of the principal suppliers of

this equipment, Spencer microscopesare used to aid in solving the metal-lurgical problems, involved and in main-taining quality of manufacture.

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SCIENCE-ADVERTISEMENTS VOL. 100 N4 25911&-