MAY 7, 1943 SCIENCE-ADVERTISEMENTS 9

NEW TEXTS FOR WARTIME COURSESIN NAVIGATION

Navigation and Nautical AstronomyBy LYMAN M. KELLS, WILLIS F. KERN and JAMESR. BLAND, United States Naval Academy. In press-ready in June

Three authors nationally known for their outstandingpublications in trigonometry have produced a text innavigation and nautical astronomy characterized by ex-ceptional clarity and simplicity. The mathematicalbackground included makes it easy for the student tounderstand the essential topics of navigation, which arearranged in logical order, lucidly explained, profuselyillustrated, and presented with numerous simple exer-cises and problems actually arising in practice.

Piloting and Maneuvering of ShipsBy LYMAN M. KELLS, WILLIS F. KERN and JAMESR. BLAND. 200 pages, 6 x 9. Textbook edition,$2.00

Represents the first four chapters of Navigation andNautical Astronomy, published as a separate volume.It explains, simply yet accurately, the fundamental prin-ciples of piloting, and applies elementary vector theoryto the relative movement of ships, torpedoes, and air-planes. Two chapters give the mathematical back-ground, the important definitions, and a brief treatmentof instruments.

Radio Navigation for PilotsBy COLIN H. MCINTOsH, American Airlines, Inc.175 pages, 51 x 8. Textbook edition, $2.00

Radio navigation is here presented from an aircraftpoint of view and is strictly limited to the practicaltreatment demanded by pilots. Approximately half ofthe book is devoted to radio range navigation and neces-sary flight techniques, and the other half to radio-direc-tion finding as a navigational aid.

Air Navigation. New third editionBy P. V. H. WEEMS, Lieut. Comdr., U. S. Navy,Retired. 406 pages, 6 x 9. Textbook edition,$3.50

The latest methods and equipment used in air naviga-tion by piloting, dead reckoning, radio position finding,and celestial navigation, are clearly and thoroughly ex-plained in the new revised edition of this well known,widely used text. The author, out of his extensivespecialization in this field, has made the treatment com-plete and authoritative, yet so simple and direct that thebeginning student will have little trouble in understand-ing and applying the methods described.

Meteorology and Air Navigation.New second edition

By BERT A. SHIELDS, Lieut. Comdr., U.S.N.R. 288pages, 6 x 9. $2.25

A revision and expansion of Parts III and IV of theauthor's well known Air Pilot Training. A chapter onnavigation problems has been added to assist the studentin solving several types of problems that have recentlybeen given considerable prominence on the pilot's writ-ten examinations. The various steps in solving off-course problems are carefully explained and a numberof typical problems are solved, including the radius ofaction type of problem.

Air NavigationThe following seven volumes, under the general title ofAir Navigation, are included in the Flight PreparationTraining Series, Published under the Supervision of theTraining Division, Bureau of Aeronautics, U. S. Navy.

Part I. Introduction to Earth79 pages, 84Jx11. $1.00

Designed to orient naval aviation cadets to navigationthat may encircle the earth. The book gives an over-allview of the earth as a sphere, of place relationships ofwar zones, of general and climatic considerations under-lying strategy, and something of the strategic signifi-cance of military objectives.

Part II. Introduction to Navigation81 pages, 84 x 11. $1.00

Covers the basic fundamentals of navigation technique.There is a detailed explanation of the various types ofmap projections, an understanding of which is essentialfor plotting courses. Emphasis has been placed uponthe importance of thorough knowledge and accuracy.

Part III. Dead Reckoning and Lines ofPosition

60 pages, 84x11. $1.00Introduces some basic applications of the fundamentalscovered in the first two volumes. It explains how theaerial navigator records the progress of his plane overthe surface of the earth, and describes certain methodsused to check the estimated position of the plane duringflight, and the manner by which the effects of air cur-rents on the movement of a plane can be determined.

Part IV.Part V.Part VI.Part VII.

In PreparationNavigation InstrumentsRelative MovementContact FlyingNautical Astronomy and Celestial Navi-

gation

Send for copies on approval

McGRAW-HILL BOOK COMPANY, Inc.330 West 42nd Street, New York, N. Y. Aldwych House, London, W.C. 2

SCIENCE-SUPPLEMENT VOL. 97, No. 2523

SCIENCE NEWSScience Service, Washington, D. C.

THOMAS JEFFERSONTHOMAS JEFFERSON'S two hundredth anniversary was

given special observance at the annual spring meeting ofthe American Philosophical Society. For 1943 marksalso a bicentennial milestone in the history of the society.It was in 1743, the year of Jefferson's birth, that thelittle informal club called " Junto, " which BenjaminFranklin had got together to discuss scientific and otherscholarly matters, was formally organized under the fulltitle which it still retains: "The American PhilosophicalSociety Held at Philadelphia for Promoting UsefulKnowledge. "Thomas Jefferson was a young man and Benjamin

Franklin was old when the two worked together in thecause of American independence; but the two could meet

on common ground at many points. Science, especiallyphysical and mechanical science, was one of the best-established of the common fronts existing between theelderly Philadelphian and the youthful Virginian; bothliked to try to find out what made things go, and bothhad a decided bent towards the invention of ingeniousand practically useful gadgets, like Franklin's lightning-rod and heating-stove and Jefferson's improved mold-board plow.At one point, however, they diverged: Franklin was a

city businessman, Jefferson was by choice a farmer. Inthis, Jefferson was more nearly at one with his fellow-Virginian, George Washington. This aspect of Jeffer-son's life and interests was discussed at the meeting ofthe Philosophical Society by M. L. Wilson, director ofextension work in the U. S. Department of Agriculture.Owner of a hill farm (for Monticello stands on a moun-

taintop), Jefferson was one of the country's first prac-

titioners of soil conservation methods, including thecontour-plowing that is now being preached as the new-

est thing in soil-saving devices. He also introduced new

plants and improved livestock varieties brought fromEurope, and was an early believer in crop rotation.

J6fferson founded the University of Virginia (it is theone boast of achievement carved in his epitaph) just as

Franklin was active in the establishment of the Univer-sity of Pennsylvania. In one of his statements of desir-able university policy, Jefferson came out positively for

the inclusion of agricultural science among the subjectsto be taught-something of a novelty in a day when

higher education still centered almost exclusively around

the classics. Yet Jefferson is not to be counted amongeducational leaders who place sole emphasis on the scien-

tific and "practical" to the neglect of the classics and

the humanities. He was himself well educated in Latin

and Greek, but in his hands the old languages were not

"dead, " as Dr. Louis B. Wright, of the Henry E. Hunt-

ington Library and Art Gallery, pointed out. "In the

early years of the republic," Dr. Wright reminded his

hearers, "the classies had not yet foundered on the aridshores of pedantry."

Jefferson once declared: "No occupation is so delight-ful to me as the culture of the earth." Translated into

Latin, that could easily be passed off as a quotation fromthe Georgics, Vergil 's great poetic work in praise ofcountry living.-FRANK THONE.

A THEORY OF GRAVITATIONA THEORY of gravitation that makes it a push instead

of a pull, thus avoiding the bugbear of action at a dis-tance, and makes it a repulsion deep within the stars andplanets, was presented by Anatol James Shneiderov atthe meeting of the American Geophysical Union. Mr.Shneiderov holds the Russian degree of " Magister inMilitary Engineering" and is also a civil engineer. Heis at present on the faculty of the George WashingtonUniversity, where the meetings were held.

There is something occult about the motion of force ata distance, Mr. Shneiderov said. His theory is in a sense

a modernized version of the theory of the Swiss scientistLe Sage, proposed some years ago. According to thistheory, streams of particles incessantly traversing space

in all directions impinge upon the farther sides of twoplanets or other celestial objects, but are screened fromthe nearer sides by the planets themselves, and so pushthem together.

In place of streams of particles, Mr. Shneiderov sub-stitutes streams of energy. These pass through matter,losing energy as they go. He has developed a formulafor the force produced which is more complicated thanNewton's, but not as complicated as Einstein's. Outsidea planet it gives the same force as Newton's law, andagrees with Einstein when account is taken of the in-crease of mass with the speed.But inside a planet, Mr. Shneiderov gets very different

results. The attractive force diminishes below the sur-

face down to a certain level, where it becomes a repulsionwhich then increases exponentially the rest of the way tothe center. According to Newton, the attractive forcediminishes continually and becomes zero at the center.According to Mr. Shneiderov the force around the centerof the earth is so great that all atoms are disintegrated,the nuclei stripped of the surrounding electrons. Thecore of the earth thus becomes an electronic gas. "This explains why the core does not transmit transverseearthquake waves which it would if it were solid as hith-erto supposed.

These great forces in the deep interior of the earth are

mainly responsible for earthquakes, and Mr. Shneiderovbelieves that a fuller understanding of them may lead

to the possibility of predicting earthquakes long before

they happen.-MoRToN MOTT-SMITH.

MEASUREMENT OF LARGE QUANTITIESOF WATER

RADIUM in tiny quantities may be used to measure

large masses of water, but the method is not as simpleas it seems at first glance, was pointed out by Dr. Victor

F. Hess, German Nobel prizeman in physics now at Ford-

ham University, at the Washington meeting of the

American Geophysical Union.

10

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Approximately 305 pages; 6 by 9; Probable price, $4.50

EMOTION IN MAN AND ANIMALBy PAUL THOMAS YOUNG, Professor of Psychology, University of Illinois.

A new book that offers authoritative material, for study and discussion, on emotion, attitudes and motives. It isintended to promote an understanding of the individual. The data presented are of importance for students of childpsychology, education, anthropology, physiology, social and experimental psychology, and allied fields.

Approximately 415 pages; 6 by 9; Probable price, $3.50

ORGANIC SYNTHESES, Volume 23By LEE IRVIN SMITH, University of Minnesota; Editor-in-Chief.

Tested laboratory methods for preparing various organic chemical reagents in one-half-pound to five-pound lots. Thisvolume covers the preparations worked out in the past year. 124 pages; 6 by 9; $1.75

ORGANIC SYNTHESES, Collective Volume 11Edited by A. H. BLATT, Queens College, Flushing, New York.

This volume contains in revised form the material which appeared in the annual volumes 10 through 19 of "OrganicSyntheses." Modifications and improvements in procedures are incorporated, and eleven procedures not appearingin the single volumes have been added. Advances in methods are recorded.

654 pages; 6 by 9; $6.50

TEXTBOOK OF ORGANIC CHEMISTRYBy GEORGE HOLMES RICHTER, Assistant Professor of Organic Chemistry, The Rice Institute.

In this edition the content has been rearranged, and much new material has been added. Among the changes shouldbe noted: the collection of the material on natural products in a single chapter; the inclusion of an entire new sectionon the terpenes; the introduction in Chapter I of the concept of resonance; the enlargement of the chapters on ali-phatic hydrocarbons; the inclusion of new material on plastics.

Second Edition: Approx. 824 pages; 6 by 9; Probable price, $4.00

CHEMICAL SPECTROSCOPYBy WALLACE R. BRODE, Professor of Organic Chemistry, The Ohio State University.

A completely modernized edition, with revised tables for emission analysis, an up-to-date revision of the section on

theoretical spectra, an expansion of the section on quantitative emission spectra, and other important additions.Second Edition: Approx. 631 pages; 6 by 9; Probable price, College Edition, $6.50

JOHN WILEY & SONS, Inc., 440-4th AVE., NEW YORK

SCIENCE-ADVERTISEMENTS 11MAY 7, 1943

12

Some indirect means is desirable for accurately measur-

ing large quantities of water in reservoirs, where directweighing is not possible. One method that has been triedhas been to dissolve a lot of salt in the water, then collecta sample of it as it comes out of the tailrace of the power

plant and determine the salt concentration in that.Some time ago the noted French physicist, Dr. J. Joly,

suggested the use of minute amounts of radium, whichdiffuse rapidly and evenly in water, but he did not doany experimental work on the method himself. Dr. Hesshas done so, making use of a large tank in Pennsylvania,loaned for the purpose by a power company.

Sources of error were found to be more numerous thananticipated. There was a tendency for part of the ra-

dium to become tied up in insoluble form with "harden-ing" chemicals in the river water; this could be partlyovercome by adding hydrochloric acid. Minute but vari-able amounts of radium are naturally present in thewater, so that their effect has to be measured in advanceand proper allowances made. Even the type of glasswareused in the laboratory may falsify results unless greatcare is exercised. Dr. Hess concluded by cautioning hishearers not to "attempt blindly to set out to measure

large volumes of water with too little radium."

LIGNITE DEPOSITS OF THEUNITED STATES

THE huge lignite deposits in the United States are a

potential source of war power was reported to the Ameri-can Society of Mechanical Engineers by Professor C. J.Eckhardt, Jr., and C. W. Yates, of the University ofTexas. Only an insignificant fraction of the nation's939 billion ton reserve is being utilized. But soaringfuel consumption to meet war needs brings increasedattention to this low-rank fuel.

Lignite, often called "brown coal," is more widelyused in Europe than America. It appears to be a half-way station between wood and coal, occurring at a more

youthful age than its true coal relatives.Lignite contains more water and ash than ordinary

coal. But misconceptions are commonly held about theproperties of lignite that stand in the way of its more

extended use. " The failure to use appropriate gratesurfaces has caused this fuel to be maligned with regardto sifting losses from size reduction of the fuel particlesas heat is applied and moisture is driven off. Yet thewater losses are no greater than those of some of themore admirable fuels and the size reduction while thisfuel burns can be rendered inconsequential. The mostserious misconceptions relate to its tendency to undergosize-reduction processes while in storage and while beinghandled. "More than a sixth of the nation 's mineral-fuel reserve

is lignite. Principal deposits are mainly in Texas, Mon-tana and the Dakotas, where no mountain-making move-

ment of the earth's crust has occurred.

ITEMSOCEAN current surveys for the Navy will be made this

spring on the Atlantic Coast by floating radio robots-

VoL. 97, No. 2523

boat-like metal buoys with radio masts fifteen feet high.A streamlined meter containing a compass will be sus-

pended from each buoy to record the velocity and directionof the current. It automatically broadcasts this to themother ship. At the receiving end, the radioed impulsesof the meter are recorded by a robot mechanism in groups

of three; the distance between two of the "ticks" givingthe velocity and the location of the third between themgiving the direction of the current. Dr. L. 0. Colbert,of the U. S. Coast and Geodetic Survey, speaking beforethe American Geophysical Union stated that the new radiocurrent meter decreases the number of vessels needed forsuch a survey as simultaneous observations can be madeat several current stations. Another advantage is thatthe streamlined current buoys can remain at their postsduring bad weather and in strong currents with less diffi-culty than a ship anchored under similar conditions.

A PHOTOGRAPHIC recorder used to replace previous meth-ods of obtaining a series of wind velocity measurementswas described at the meeting of the American GeophysicalUnion by Dr. Leonard B. Corwin, of the U. S. Soil Con-servation Service. Dr. Corwin stated that the recorderwas developed to secure simultaneous measurements ofwind velocity at several different levels where electricalpower was unavailable. The dials or faces of severalcounters were photographed as the simplest and surestway to obtain multiple records. By adjustments, photo-graphic observations could be obtained at intervals of one

minute up to an hour or more. Dr. Corwin stated thatthe photographic recorder "appears to offer a means ofobtaining an autographic record of many if not mostmeteorologic and climatic values." Further simplifiea-tion of the apparatus is contemplated.

SYNTHETIC plastic material to supplement the availablesupply of mica necessary in war-used electrical equipmentis promised in the near future. Priorities have beengranted for the materials to construct a plant where thesynthetic product will be made. It is expected that theplant will be in production about July 1. The materialis a synthetic polymerized resin. It is reported to havehigh temperature resistance and low dielectric loss. Theseproperties will permit its use in several types of radio

equipment now requiring mica. It will be known under

the trade name of Polectron. This new plastic is a prod-uct of the General Aniline and Film Corporation. It has

been tested for the corporation by the laboratories of the

Massachusetts Institute of Technology and those of one

of the large industrial companies making electrical appa-ratus. It has been tested also at Wright Field. Much

of the mica now in use is obtained from India and Brazil.

It has been called by the War Production Board an

urgently needed raw material vital to mechanized warfare,and mica users and fabricators were warned many months

ago to conserve the supply in every way possible. One

ton of the new plastic, fabricated into mica replacementmaterial, will replace from ten to fifteen tons of the im-

ported block mica, it is expected, thus saving much

strategic material.

SCIENCE-SUPPLEMENT

MAY 7, 1943 SCiENCE-ADVERTISEMENTS 13

AerialPhotographsAND THEIR APPLICATIONS

By H. T. U. SMITHASSISTANT PROFESSOR OF GEOLOGY, UNIVERSITY OF KANSAS

TJHIS is a practical, profusely illustratedtext that provides a working knowledge

of the simpler methods of making mapsfrom aerial photographs and places greatestemphasis on the interpretation and use ofaerial photographs, with special reference tothe needs of the geologist, geographer, en-gineer and military scientist. Contrary toother books in its field Smith's Aerial Photo-graphs and Their Applications deals withmap-making as a means to an end, ratherthan as an end in itself, and stresses the de-tails of practical procedure instead of dis-coursing on confusing theoretical matters.A large number of its illustrations are ar-ranged for stereoscopic examination. To bepublished in May.

Mineralsand Rocks

By R. D. GEORGEEMERITUS PROFESSOR OF GEOLOGY, UNIVERSITY OF COLORADO

THIS new book presents a concise, well-organized, and broadly inclusive discus-

sion of the ever-increasing number andvolume of earth materials, both metallicand non-metallic, which have become essen-tial to present-day industries and have beeninstrumental in enriching life. Each ele-ment is fully described, its uses, both aloneand in compounds, are explained; and theminerals from which it is derived are de-scribed. The illustrative material includesline drawings and photographs, picturingcrystal forms, ore bodies, rock structure,apparatus, etc., and diagrams representingthe chemical and mineral compositions ofthe rock families. Price, $6.00.

D. Appleton - Century Company35 W. 32nd St. New York, City

THE VERTEBRATE EYEAND ITS ADAPTIVE RADIATION

By Gordon Lynn Walls"It should certainly be read by all biologists including medicalmen, interested in visual problems."-Nature"It is a 'must' book for every biologist, whatever his spe-cialty."-Journal of Mammalogy."Never before has so much light been shed at one time on ananimal organ . . . a tremendously interesting and valuablebook."-American Naturalist

Published 1942. 785 pages, 197 figures, $6.50Orders sent postpaid within the continentalUnited States upon receipt of remittance.

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Today the products of Kewaunee Manufacturing Com-pany, whether for the Scientific Laboratory or for otherwartime needs of America and her allies, continue tobe distinguished by their efficiency in service.

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full instructions. Price $2.00 f.o.b. Towson, Baltimore,Maryland.

LaMotte Chemical Products Co.Dept. H. Towson, Baltimore, Maryland

MAY 7, 1943 SCIENCE-ADVERTISEMENTS 13

14SINEAVRIEET O.9,N.22

Justed Published

PHYSIOLOGICAL REGULATIONSBY EDWARD F. ADOLPH, Ph.D.

Associate Professor of Physiology in the University of Rochester

A valuable Reference and Laboratory Aid for Physiologists, Biologists andall other science workers interested in metabolisms.

The major subjects of this study are: Water exchanges in animals;Rates of certain classes of physiological processes; Quantitative compari-sons of like functions in diverse species and individuals; Organ and tissueexchanges; Similarities and contrasts in the metabolisms of diverse com-ponents.

Water Exchanges of DogOther Types of Water Increment (Dog)Variabilities of Water Relations (Dog)Water Relations of ManWater Relations of FrogWater Relations of Other SpeciesEquilibrations in Parts of OrganismsGeneral Features of Water ExchangesSome Other Correlatives of Water Content (Dog)Some Other Correlatives of Water Content (in Other

Species)

495 pages 46 tables

rE NTSFurther Correlatives of Water Content and Ex-

changesWater Balances and Exchanges; RecapitulationsHeatDiverse ComponentsUniformities and Comparisons among ComponentsChoosing Physiological VariablesPhysiological RegulationsSome Speculations Concerning RegulationsConclusions, References and Index

186 graphs price $7.50

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VoL. 97y No. 252314 SCIENCE-ADVERTISEMENTS

MAY 7, 1943 SCIENCE-ADVERTISEMENTS 15

4 w ~AERODYNAMIC111l FORCES

No. 75441 Airplane Forces Ap-paratus as illustrated but with-

out support stand or cambered

wing section.

Eac

HIS Cenco-Hutchinson airplane apparatus demonstrates and measures the lifeand drag resulting from relative motion between a section of airplane wing and

the air.In use, the wind velocity may be maintained substantially constant and the angleof attack varied; or the angle of attack may be kept constant and the wind velocityvaried.The apparatus consists of a model section of an airplane wing which may beclamped in supporting arms so that the angle of attack-or the angle between thesection and the direction of the wind velocity-may be varied. The wing, or air-foil section, is counterpoised by weights slidable on extensions of the arms on theopposite side of pivots, which are mounted in a swinging frame. The frame itselfswings on a horizontal axis; it is carried by substantial vertical supports. Meansare provided on the horizontal arms to counterbalance the lift and on the swingingframe, the drag. These consist of graduated arms with rider weights and indi-cators to show the condition of balance.

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MAY 7, 1943 SCIENCE-ADVERTISEMENTS 15

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16 SCIENCE-ADVERTISEMENTS VoL. 97, No. 2523

A1-0

MAY7,1943 SCIENCE-ADVERTISEMENTS 17~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

SOLTYSACTIVE HYDROGEN APPARATUS

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18 SCIENCE-ADVERTISEMENTS VOL. 97, No. 2528

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18 SCIENCE-ADVEPTISEMENTS VOL. 97; No. 2523