MARCH 29, 1940 SCIENCE-ADVERTISEMENTS 9

McGraw-Hill Books in Photography

ELEMENTARY PHOTOGRAPHYBy GILFORD G. QUARLES, University of Alabama. 351 pages, 6 x 9. $3.00

Here is a book designed to fill the need for a text on photography intermediate between very ele-mentary ones and those of an advanced, technical nature. Thus the present volume assumes noprevious knowledge of the subject, and follows what the author believes to be the normal order oflearning rather than the normal order of the photographic process. Besides descriptive materialcovering the most generally used apparatus, actual working instructions are given for carrying outall the processes discussed.

THE Handbook of Photography. By KEITHHENNEY and BEVERLY DUDLEY. 871

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KEITH HENNEY. 281 pages, 5t x 8. $3.50By JULIAN E. MACK, University of Wis-consin, and MILES J. MARTIN, Milwaukee New Ways in Photography. By JACOBExtension Center, University of Wiscon- DESCIN. 307 pages, 5 x 8. $3.00sin. 575 pages, 7 x 91. $5.00

In this book the authors give a unified, cor- Making Pictures with the Miniatureprehensive treatment of photography, cover- Camera. By JACOB DESCHIN. 251ing thoroughly and accurately every aspect pages, 5 x 8. $3.00of the process, from optics, lenses, cameras,exposure, development, etc., to scientific and

Finding New Subjects for Your Camera.pictorial photography. The manual section Finding New Subjects for Your ameraof the book gives working directions for a By JACOB DESCHIN. 239 pages, 5 x8.variety of specialized operations, including $2.50lens testing, the use of polarizing discs, sensi-tometry, color photography, etc. Through- Lighting Ideas in Photography. Byout, details are considered as special examples WILLIAM HERRSCHAFT and JACOBof the general principles outlined, in order DESCHIN. 278 pages, 6 x 9. $2.75that the student may be prepared to cope withnew problems as they arise.

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MARCH 29, 1940 SCIENCE-ABDVERTISEMENTS' 9

SCIENCE-SUPPLEMENT

SCIENCE NEWSScience Service, Washington, D. C.

THE ECLIPSE OF THE SUN(Copyright, 1940, by Science Service)

FOR the first time in eight years, on Sunday, April 7,the entire United States will be able to see an eclipse ofthe sun. This coming solar display will be a partialeclipse over the whole nation. The nearer one lives tosouthern Texas and the Gulf States the. larger will be theapparent "bite" which the moon will take out of thesun's disk.

In the 150-mile wide band that enters southern Texas,follows the Gulf of Mexico coastline and passes overnorthern Florida, will occur one of the unusual andpleasing annular, or ring, eclipses. For times varyingfrom over 6 minutes to 5i minutes, observers in this bandwill see the black shadow of the moon nearly coveringthe sun's disk. The moon's diameter will cover 92 percent. of the sun's diameter, to be exact.

This means that observers, during the eclipse, will seethe sun as a thin ring of light instead of its flaming disk.

Farther north, outside of the annular band, observerswill see a partial eclipse. Far to the north and west inOregon and the state of Washington the moon will blockout 40 per cent. of the sun's diameter. Other sections ofthe nation will see the partial eclipse as shown on theadjacent map. The symbols at the left show the relativesize of the sun's disk that is covered.The exact direction in which the moon will start to

block out the sun's disk is not given on the map correctlyfor all observers because this direction differs for everylocality.

The longest time in which the moon will nearly coverthe sun's disk will be in southwestern Texas, where theduration of the eclipse will be 6 minutes, 37.6 secondsaccording to calculations at the U. S. Naval Observatoryin Washington. As the eclipse progresses eastward alongthe annular band the duration becomes shorter and willbe only 5 minutes, 38.8 seconds at the line marked off thecoast of Florida.

For all those who view the eclipse smoked glasses, or a

piece of photographic film exposed and densely blackened,are necessary. Serious damage can be done to the eyesby a glance at the sun's flaming surface without this aid.

There was a time when annular, or ring, eclipses suchas that of April 7 were almost entirely without scientificinterest. The progress of research, however, and ad-vances in scientific instruments have made possible usefulscientific observations on the coming solar event.With special thermocouples and infra-red filters an

expedition of the University of Chicago and the Univer-sity of Texas will go from McDonald Observatory at Mt.Locke, Texas, down into better observing position'andseek to study the faint light on the sun's limb (its outeredge) which is normally obscured by the much morebrilliant rays from the center of the sun's disk. At Mc-Donald Observatory, itself, will be set up the televisionapparatus invented by Dr. A. M. Skellett, of the Bell.Telephone Laboratories, for viewing the sun even when

an eclipse does not occur. This device works well evenwhen the sun's light is not blocked off by the moon.With an eclipse of about 90 per cent. magnitude sched-uled for McDonald Observatory it is believed that evenbetter pictures can be obtained because of the moon'shelp.

Journeying from Washington to near San Antonio,Texas, will be the expedition of the National Bureau ofStandards and the National Geographic Society whichwill study the eclipse by radio signals and the behaviorof the ionized reflecting layers far above the earth. Withtrailer-mounted equipment scientists will study the timeof the radio "echo" signals during different stages ofdarkness.At the Kensington Laboratory of Carnegie Institu-

tion's Department of Terrestrial Magnetism, Dr. L. V.Berkner will also investigate these radio reflections dur-ing the entire day of the eclipse. From the lower reflect-ing layers (at heights of 60 and 130 miles above theearth) it is hoped that data can be secured which willtell how fast the ions in the atmosphere recombine. Inupper regions of the ionosphere (at heights of 220 miles)the general behavior of the reflections during the eclipsewill be studied. Past investigations seem to show thatthere is no general pattern for this behavior during theprevious eclipses. The eclipse at Kensington, just out-side Washington, will be about 65 per cent. total.Amateur astronomers can aid science by observing the

time of first and last contact of the moon and the sun.To take this information so that it will have meaning,it is necessary to have an accurately calibrated chronome-ter for noting the time, and the exact geographical loca-tion where the observation was made. One can not simplygo out in the backyard with a watch and do the job.Science Service will gladly forward the data obtained byamateurs to astronomical centers for study and possibleuse.-ROBERT D. POTTER.

HIGH PRESSURE(Copyright, 1940, by Science Service)

SCIENTISTS stand at the threshold of experimentswhich should enable them to duplicate pressures en-countered 745 miles down inside the earth, and doublepresent world's record pressures of 3,000,000 pounds tothe square inch and over.The record high pressure, equaling pressures more than

100 miles within the earth, has been obtained by twoscientists of the Carnegie Institution of Washington, Dr.Roy W. Goranson, of the Geophysical Laboratory, andEllis Johnson, of the Department of Terrestrial Magne-tism, with a "cascade bomb" apparatus. Their resultsvirtually duplicate the high pressure of 3,000,000-3,500,-000 pounds per square inch reported-by Professor P. W.Bridgman, of Harvard University, in the Physical Reviewlate last month.The only reason the Carnegie experiment was stopped

at 3,000,000 pounds per square inch, or 200,000 atmos-

10 VOL. 91, No. 2361

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VERTEBRATE ZOOLOGYBy WILLIAM HENRY ATWOOD

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Throughout the selecting, assembling andwriting of the materials of this textbook thepossibilities of its use in three types of courseshave been constantly kept in mind. 1. Pri-marily it is a text in vertebrate zoology, andas such may be used in a semester coursedevoted exclusively to that subject. 2. Ingeneral zoology courses where invertebratesare studied the first semester and the verte-brates the second semester this text should bevaluable. 3. In vertebrate anatomy courseswhere two or three types are dissected, thistext with the lectures should provide a valu-able orientation of subject matter.

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pheres, was that the pressure gauge used was not cali-brated beyond that point. The pressure equipment itselfpotentially may be capable of doubling this pressure.If this can be done, it will produce a pressure equal tothat inside the earth at depths of 745 miles and permitimportant studies of the properties of matter at thesepressures.Announcement of the Carnegie's new cascade bomb

equipment was a dramatic highlight of the Conferenceon Theoretical Physics sponsored annually by the Car-negie Institution and George Washington University.Those present heartily applauded the new high-pressureachievement which was performed in an intensive all-night research by Dr. Goranson and Mr. Johnson. Itwas at this same conference, just a year ago, that thedramatic announcement was made to America that sci-ence had found a way to split uranium atoms withneutrons and make them yield enormous amounts ofatomic energy. A friendly race between Harvard andthe Carnegie Institution appears to be in progress toattain world's record high pressures.

The secret of the amazing pressures attained by theCarnegie experimenters is the use of cascade bomb appa-ratus. This device consists of two pressure chambersarranged one inside the other so that the inner one issurrounded with a kerosene-like oil known as varsol undera pressure of 17,000 atmospheres, or 255,000 pounds tothe square inch.-ROBERT D. POTTER.

NEW TYPE RADIO SETS(Copyright, 1940, by Science Service)

WITHIN a year new types of radio receivers for detect-ing the crystal clear frequency modulated (FM) radiotransmission will be selling for $33, was predicted byMajor Edwin H. Armstrong, radio inventor and professorof electrical engineering at Columbia University, at hear-ings of the Federal Communications Commission in Wash-ington. The present price of such receivers is $65 but isbased only on production of 1,000 receivers. Major Arm-strong testified that the price can be cut in half withgreater production, and that this reduction should come

within a year.Major Armstrong told the FCC that if these receivers

were plugged into console radio-phonograph receiversnow in use, through the jack for the phonograph record-playing, greatly superior performances could be achieved.The large-sized speaker in these console sets, he indicated,allowed present receivers to utilize the added tone bril-liancy and fidelity possible with FM reception. A small-sized loud speaker, used with FM receivers, would permitsome gain in performance but not very much.Under examination before the FCC it was brought out

that Major Armstrong has received $755,000 from thesale of his three outstanding radio patents: the re-

generative circuit, the super-heterodyne circuit and thesuper-regenerative circuit. All this money, he testified,he has poured back into the development of his new FM

system.It was disclosed that Major Armstrong receives no

royalties from the manufacturers of FM transmitters but

rPPLEMENT VOL. 91, No. 2361

only a lump sum payment which ranges from $300 fora small 250-watt transmitter to $5,000 for the largestpower. If the transmitter manufacturer will promise tospend a sum for research on FM equal to this amountMajor Armstrong waives his fees and receives nothingfor licensing the transmitter manufacturer. The FCCcommissioners carefully questioned Major Armstrong onhis assertion that with FM radio and directive antennasit is possible to separate two stations broadcasting on thesame frequency when the ratio of their signal strength isonly two to one. In present type of broadcasting a sig-nal ratio of 20 to one is needed for this feat.Major Armstrong has received 15 patents, dating from

December, 1933, on the new frequency modulated radiosystem, but he has studied it, off and on, for the last 20

years.-ROBERT D. POTTER;

OPTICAL TESTS FOR DETERMINING THEPRESENCE OF CANCER

(Copyright, 1940, by Science Service)A NEW optical test that tells whether a person has

cancer and whether after operation that cancer has beensuccessfully treated is claimed by Dr. M. W. Mettenleiter,New York surgeon, connected with St. Clare's Hospital.In a preliminary series of 325 cancer cases, the test isreported to have proved 96 per cent. correct.

Developed from German studies reported over the lastthirty years, the Mettenleiter test involves the measure-ment of the densities of a number of samples of the per-son's blood serum by use of an interferometer. Theblood serum from the patient is mixed with an extract ofhuman cancer cells from a patient known to have carci-noma of the breast.Varying amounts of the suspected patient's blood

serum are placed in four test-tubes containing equalamounts of the cancer extract. After incubation andsettling, the densities of the four dilutions are obtained,and plotted out graphically. The curves are reported toshow a characteristic difference between cancerous andthe non-cancerous blood serum.

Dr. Mettenleiter believes that the test will prove ofassistance in the early diagnosis of cancer and in de-termining the course of a case. He finds that a curve

indicating cancer slowly changes to a normal curve aftera successful operation. He reports that it changes againfrom a normal to a cancer curve in the earliest stages ofrecurrence. A cancer curve, it was found, does not

change postoperatively if metastases or spreading of thecancer have already or are about to take place elsewherein the body.The test reaction failed to appear when serum of a

pregnant woman or of a person with tuberculosis, syphilisor numerous other diseases was used, it was reported.However, as was to be expected, fever and intensive x-raytreatments influenced the serum so as to make the testuncertain. Extract of normal organs, for example, fibroidtissue, failed to show any reaction.

Dr. Mettenleiter made known his researches througha communication to the British science journal, Nature.He is a fellow of the American Medical Association and

_. __ __ __ ____

7

SCIENCE-SU

of the American College of Surgeons. Born and educatedin Germany, he has practised in New York since 1927.A successful, practical test for cancer has been sought

by many experimenters. About a score of such tests havebeen announced from time to time. The Mettenleiter testwill undoubtedly be received with interest. Others work-ing on cancer will try it and they must report successbefore it can be expected to come into use.-WATSONDAVIS.

CANCER AND SUNLIGHT(Copyright, 1940, by Science Service)

PREVENTING cancer by sunlight may be possible if morecan be learned about how the sun's rays affect the body.Evidence that exposure to sunlight does produce cancer

immunity in some cases was presented by Dr. Frank L.Apperly, Medical College of Virginia, at the meeting inPittsburgh of the American Association of Pathologistsnd Bacteriologists.Cancer mortality in the United States and Canada,vs less, Dr. Apperly finds, as the amount of sunlightases across the continent and as more people are

'd to sunshine, for example, where more of the..ation is engaged in farming or other outdoor

occupation.Differing from some others who believe sunlight holds

the key to cancer prevention, Dr. Apperly does not be-lieve it is necessary to have skin cancer in order tobecome immune to other forms of cancer. Those whohold this view believe cancer deaths might be reduced byenough sunlight to cause skin cancer, which is easilycured, and which might leave the individual with immun-

ity to other more killing forms of cancer.

Sun rays, or something closely associated with them,according to Dr. Apperly, have two separate effects: (1)They produce some sort of relative immunity to cancer

in general and, in those localities where the mean tem-perature is less than about 42 degrees Fahrenheit, even

to skin cancer; (2) at mean temperatures above 42 de-grees Fahrenheit, sun rays produce more cancer on thoseparts of the skin exposed to them, in spite of a generallyraised immunity.

Besides the statistics of cancer deaths in various cli-mates, Dr. Apperly cited animal studies by other investi-gators which, though not completely applicable to humans,have a bearing on the question. When mice were givena large dose of x-rays before application of a cancer-

causing coal tar chemical, methylcholanthrene, they diedat almost three times the rate of animals not previouslyx-rayed. Small doses of x-rays before the chemical treat-

ment, however, protected the mice against the cancerous

effect of the chemical to such an extent that the cancer

mortality was only one third that of the non-x-rayedgroup. "We may be able to reduce our cancer deaths,"Dr. Apperly concluded, "by inducing a partial or com-

plete immunity by exposure of suitable skin areas to sun-

light or the proper artificial light rays of intensity andduration insufficient to produce an actual skin cancer.

The study of the effects of sunlight on the living organ-ism, and of those conditions in the skin which modifyits action, may produce results of inestimable value."

rPPLEMENT 13

ITEMSTHE report of papers presented at New Orleans before

the Federation of American Experimental BiologicalSocieties, printed last week, should have been signedJane Stafford, medical staff writer of Science Service.

SPRING farm work has been delayed a full two weeksin many sections of the East and Central Valley regions,by continuing cold, wet weather, the U. S. WeatherBureau's weekly survey shows. At this time last year,farmers were troubled by an exactly opposite state ofthings: a persistent spring drought that even made itselfseverely felt in Florida. Dry weather, however, has pre-vailed in the nearer Southwest, from upland Arkansas to

Texas, where corn planting has had to be postponed in

many communities until rains come. Early cotton plant-ings show poor stands in Texas, and little is up at all inother parts of the western Cotton Belt. In eastern cottonstates planting still awaits drier soil and warmer weather.The Plains area reports conditions ranging all the wayfrom a severe dust storm in Oklahoma to unworkably wetfields in Montana. In general, Plains farms have ade-quate topsoil moisture at present.

THE extreme precision needed in modern airplanemanufacture requires the use of rivets which have been

kept chilled at the temperature of dry ice. At the worksof the Boeing Aircraft Company, at Seattle, Washington,special heat treatment is given to aluminum alloy rivets.

They are then placed in refrigerated boxes at dry ice

temperature which retards their aging, or hardening,characteristics. As used they are removed from the boxesand quickly driven into place.

THE medical care and health service plan which thisnation finally adopts will be that one of the various pro-posed plans which captures the public's imagination,according to the prediction of J. Douglas Colman, di-rector of the Associated Hospital Service of Baltimore.The most obvious channel through which health services

might flow is, of course, that of government, Mr. Colmansaid in a discussion of medical care at the Johns Hop-kins School of Hygiene under the De Lamar Foundation.Other channels are private enterprise, the cooperativemovement and local voluntary effort as exemplified "inour voluntary hospital system and more recently in

Hospital Service Plans. Already there are indications ofmarkedly increased activity in each of these fields. Prob-

ably each one of them will contribute in some measure

to an ultimate solution and probably under each one ofthem a fairly workable program could be developed.Certainly the choice will be made by the public, and interms of the one which can most capture its imagination.During 1940, the 56 non-profit hospital service plansapproved by the American Hospital Association, he re-

ported, will provide their 4,500,000 subscribers with ap-proximately $25,000,000 worth of hospital service. Sub-scribers to these plans have increased from about 50,000in 1935 to the present 4,500,000.

MARCH 29, 1940

14 SCIENCE-ADVERTISEMENTS VOL. 91, No. 2361

THE SCIENTIFIC MONTHLYJ. McKEEN CATTELL, F. R. MOULTON and WARE CATTELL, Editors

CONTENTS FOR APRIL

SCIENCE AND SOCIAL EFFECTS: THREE FAILURES. PRESIDENT ISAIAH BOWMAN.SEVENTY YEARS OF SUEZ. PROFESSOR W. 0. BLANCHARD.MANAGEMENT OF AQUATIC WILDLIFE IN THE GREAT BASIN. PROFESSOR ANGUS M. WOODBURY.DEVELOPMENT AND MANUFACTURE OF OPTICAL GLASS IN AMERICA. M. HERBERT EISENHART AND EVERETT

W. MELSON.ANALYSIS OF WORLD'S FAIRS' HEARING TESTS. H. C. MONTGOMERY.ORGANISM, SOCIETY AND SCIENCE. I. PROFESSOR R. W. GERARD.MUSICAL INHERITANCE. PROFESSOR CARL E. SEASHORE.THE "CHAIR" FOR INSECTS? DR. ROBERT C. MURPHY."MIND IS MINDING," BUT OR STILL. But, PROFESSOR JARED S. MOORE; Still, PROFESSOR LESLIE A. WHITE.BOOKS ON SCIENCE FOR LAYMEN:

Children's Science Books Published in 1939; Photographing the Invisible; The Life of the Mind; The Rise of Civilizttion.

THE PROGRESS OF SCIENCE:Centenary Celebration of the Wilkes Exploring Expedition; National Zoological Park Expedition to Liberia; Impor-tance of Grassland Reserves; Endocrine Glands and Their Disorders; Dispelling Fog; Average Use of Mechanical Power.

CONTENTS FOR FEBRUARY

GEOLOGY AND CLIMATOLOGY FROM THE OCEAN'ABYSS. DR. WILMOT H. BRADLEY.

WILLIAM BARTON ROGERS, PIONEER AMERICANSCIENTIST. DR. ARTHUR BEVAN.

NATURALISTS IN THE WILDS OF BRITISH COLUM-BIA. II. JOHN F. AND THEODORA C. STANWELL.FLETCHER.

"THE APOTHEOSIS OF SCIENCE." ROBERT LOVELLBLACK.

COOPERATION IN ASTRONOMY. DR. OTTO STRUVE.WHY WE EAT WHAT WE EAT. DR. WARREN T.

VAUGHAN.VIEWS ON MACHINERY AND UNEMPLOYMENT. PRO-

FESSOR C. E. DANKERT.TELEPATHY-A SURVEY. PROFESSOR SUMNER BOYER

ELY.STUDIES IN MOSQUITO BEHAVIOR. DR. JOHN A.

MILLER.BOOKS ON SCIENCE FOR LAYMEN:

Can the Disabled Exercise?; A Catalogue of PoisonousPlants; Tribute to a Scientific Leader; Drama AmongFossils.

THE PROGRESS OF SCIENCE:The American Association for the Advancement of Sci-ence; The Columbus Meeting in Retrospect; NewlyElected President; Award of the One Thousand DollarPrize; Symposium on Blood, Heart and Circulation;The Scientific Exhibition; Washington Dinner in Honorof Julian S. Huxley.

CONTENTS FOR, MARCH

THE FUTURE OF MAN AS AN INHABITANT OF THEEARTH. PROFESSOR KIRTLEY F. MATHER.

THE ROLE OF CHANCE IN DISCOVERY. PROFESSORW. B. CANNON.

NATURALISTS IN THE WILDS OF BRITISH COLUM-BIA. III. JOHN F. AND THEODORA C. STANWELL-FLETCHER.

TWENTY-FIVE YEARS' QUEST OF THE WHALESHARK. DR. E. W. GUDGER.

SOME GEOGRAPHIC ASPECTS OF THE MANUFAC-TURE OF MEZCAL. DR. RAYMOND E. CRIST.

EXPLORING THE CHEMICAL CAUSES OF CANCER.DR. GRAY H. TWOMBLY.

THE SPACE IN WHICH WE LIVE. DR. PAUL R. HEYL.SCIENCE IN AN UNFRIENDLY WORLD. DR. W. JAMES

LYONS.THE SOCIAL SIGNIFICANCE OF SCIENCE. HENRY M.WRISTON.

MEDICINE IN THE BIBLE. DR. CHARLES WEISS.BOOKS ON SCIENCE FOR LAYMEN:

Some Pioneer Psychologists; From the Dawn of Sur-gery; To Find a Snake; In the Tidal Zones; A Nation-Wide Institution.

THE PROGRESS OF SCIENCE:The Nobel Prize Award in Physics for 1939 to E. 0.

Lawrence; The Centenary of the Discovery of the Vul-canization of Rubber; Opening of the BuhI Planetariumand Institute of Popular Science in Pittsburgh; MoreSpeed in Camera Lenses; House-Heating by SolarEnergy.

PUBLISHED FOR THE AMERICAN ASSOCIATION FOR THEADVANCEMENT OF SCIENCE

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