FEBRUARY 11, 1944 SCIENCE-ADVERTISEMENTS 9

,f necki~ 7k £5a Fe' SW~e

Storer's

GENERAL ZOOLOGYBY TRACY I. STORER

Professor of Zoology, University of California at Davis

McGraw-Hill Publications in the Zoological Sciences

798 pages, 6 x 9, 551 figures, 5 colored plates. $3.75

This effectively organized basic text has already been adopted by over 60 colleges anduniversities. The following institutions are representative:University of ArizonaBrown UniversityUniversity of CaliforniaUniversity of California at

Los AngelesCornell UniversityDuke UniversityFresno State CollegeHaverford CollegeUniversity of IllinoisKansas State CollegeLouisiana State University

Massachusetts State CollegeMiami UniversityMills CollegeUniversity of MontanaUniversity of North CarolinaUniversity of Notre DameUniversity of OregonPomona CollegeQueen's UniversityReed CollegeRice InstituteSan Diego State College

San Jose State CollegeUniversity of Southern CaliforniaUniversity of South DakotaSyracuse UniversityTexas Technological CollegeUniversity of TorontoTufts CollegeUniversity of UtahUniversity of VermontUniversity of WashingtonWellesley CollegeWells College

"I have made a careful examination of this book and sincerely believe that it is the best textbook ingeneral zoology that I have ever seen." Professor H. W. CURRAN

Queen's University"I have explored its pages carefully and can say unhesitatingly that no zoology text of recent yearshas caught my eye to the extent that it has. I predict for it a very high place among the outstand-ing American textbooks in zoology." Professor H. M. HARRIS

Iowa State College"It is a very fine book, in the production of which both the author and publisher may well be proudof their achievement." Professor HAROLD KIRBY

University of California"Professor Storer should be congratulated on his success in setting forth the principles underlyinganimal biology, and yet including a comprehensive, systematic survey of the animal kingdom withinthe confines of a single volume." Professor B. P. YOUNG

Cornell University

Send for a copy on approval

McGRAW-HILL BOOK COMPANY,- Inc.330 West 42nd Street, New York 18, N. Y.

FEBRUARY 11, 1944 SCIENCE-ADVERTISEMENTS 9

Aldwych House, London, W.C. 2

SCIENCE-SUPPLEMENT VOL. 99, No. 2563

SCIENCE NEWSScience Service, Washington, D. C.

SX CASSIOPEIAEA STAR that appears to be "playing catch" with itself,

tossing a part of its own flaming atmosphere far out intospace, clear around its companion in a double-star teamand recovering part of it on its return trip, is describedby Dr. Otto Struve, of the Yerkes Observatory, in TheAstrophysical Journal.

The star is a rather faint double one, designated byastronomers as SX Cassiopeiae. Cassiopeia is the con-

stellation landmarked by the great W-shaped group ofstars on the opposite side of the Pole Star from the GreatDipper.As Dr. Struve pictures the phenomeon, a stream of gas

issues from one member of the double-star team anddivides on the far side of the second member. Part ofthe stream flows off into space, while part circles aroundthe second star and returns to rejoin the atmosphere ofits parent star. Some tenuous, absorbing cloud of gases

acting in this manner would explain the peculiar varia-tions observed in the case of SX Cassiopeiae.A powerful stream of cool but rapidly moving gas flows

out from the G star toward its companion. One part ofthe stream, presumably composed of the more distant or

more rapid strata, expends outward and leaves the sys-

tem. The other part flows around the A star, and havingbecome hotter, but traveling more slowly, ultimately re-

turns to the G-type star. It is not possible to see thisstreaming action, but spectroscopic studies make this themost plausible picture.

The stream of ionized metals such as calcium and ironflows at a height above the surface of the A star aboutequal to the star 's diameter. According to Dr. Struve,"The most interesting feature of SX Cassiopeiae is theobservation of an approaching shell at and near sec-

ondary eclipse. These motions are plausibly attributedto the turning over of the stream due to conservation ofangular motion. Only a part of the stream is retainedby the system and completes the entire circuit around theA star. "

The spectrum of this eclipsing double star is a blendof a true star of the G type, to which class the sun be-longs, and lines of another origin which resemble theshell lines of an A star, a type which has much hydrogenin its make-up. The giant G-type star, which ejects thestream of gas, is believed to be larger than the luminousA-type star. The relative masses of the two, however,have not as yet been determined. The A star is com-

pletely eclipsed once every 36.567 days, giving a chance toto study the G star directly. But the streams of gas fromthe G star are projected upon the disk of the bright Astar, so that a clear view of it is never realized for study.

That SX Cassiopeiae is not just a simple system of twoeclipsing stars was discovered by Mme. L. Ceraski at Mos-cow in 1907. Peculiar variations in the star's velocitycurve were observed by A. H. Joy at the Mount WilsonObservatory. These, Dr. Struve believes, are probably dueto changes in the density of the gas within the streams."The entire picture is very similar to that observed in

Beta Lyrae, " he states, " only here the smaller, andprobably less massive star, is the bright A-type com-

ponent."

THE POST-WAR STEEL INDUSTRYIN a report to the American Chemical Society, Dr. John

M. Weiss, New York industrial chemist, expresses theopinion that aluminum and magnesium will not seriouslymenace the steel industry after the war, neither willplastics. Nor will the use of plastics be a hindranceto light-metal developments.The yearly capacity of the steel industry is approxi-

mately 100,000,000 tons, the estimated capacity figuresfor aluminum and magnesium are 1,500,000 tons and300,000 tons respectively, he states. The production'capacity of the light metals is less than 2 per cent. ofthe steel production. "Competition and new needs may

so stimulate the alloy steels as actually to increase pro-duction," he said, "and thereby bulwark the steel manu-

facturers. "The present large uses of aluminum and magnesium

are in airplane construction and in incendiary bombs.The latter will disappear with peace and the former willundoubtedly be sharply reduced. New uses for aluminumand magnesium reaching far beyond the transportationfield will be necessary if the plants are to continue tooperate at capacity. It is estimated that synthetic plas-tics capacity represents only about 15 per cent. of theprojected light-metal capacity.

Dr. Weiss concludes that "Many uses of plastics,notably the protective coating field, are not competitivewith the light metals. Likewise, the transparent andcolored specialty products do not fall into the competitiveclass, so that the impact on metal is even less than thetonnage figures indicate."

MONTHLY CLIMATIC MAPSA GLANCE at the series of new monthly climatic maps

of the world prepared by the Army Map Service showswhat kind of weather may be expected, on the average,

each month in the year over all six of the world's conti-nents. Each kind of climate is shown by a distinctivecolor, so all you need to do is find a matching color on

the map of North America or other familiar region, andplan accordingly. Thus, Timbuctu in June is colored up

like western Texas in July. You'll find the same coloraround Darwin, in northern Australia, right now-it'sstill high summer in the southern hemisphere.By matching colors on these new maps, the supply

officer will learn that Tokyo weather is virtually identicalwith that of Washington, D. C.; that the terrific Russianwinters are about like normal winters in northern Minne-sota, North Dakota or Maine; that the city of Duluth isclimatically about on a par with Leningrad; and thatBismarck, N. D., has a climate similar to that of Moscow.

This newly developed monthly breakdown replaces thevery general system of dividing the world into yearlyregional climates. Presenting complete information on

10

Fuui 11 194SINEA ETSMNS1

U-OW Er~Uaam4wa~~~ecc~~

-U

ELEMENTS OF BIOLOGYBy PERRY D. STRAUSBAUGH, Professor of Botany,West Virginia University, and BERNAL R. WEIMER,Dean of the Faculty and Professor of Biology, BethanyCollege, West Virginia; Authors of "General Biology"

A broad perspective of biology is offered to students at the college level in this new text-book. By means of judicious selection and condensation, the authors have presented thesubject in a form suitable for use in one-semester courses. They have also presentedbasic material which the instructor can readily adapt for use in the premedical coursesin the Army and Navy programs. Principles are stressed, together with factual materialdeveloped along functional lines. The illustrations, of which there is an ample supply,have been chosen particularly for their teaching value; they include eleven colored platesdesigned to bring out more clearly certain details and structural relationships.

ELEMENTS OF BIOLOGY meets certain very important objectives:1) It gives some training in, and appreciation of,the scientific method. The first chapter acquaintsthe student with the procedure of the scientificmethod; in addition, it introduces him to the vari-ous fields of biology and orients him to othersciences. At various points throughout the bookfurther development of the scientific method ispresented, as well as descriptions of the pro-cedures followed by scientists in making certainbiological discoveries.

2) It introduces the student to those guidingprinciples and facts of biology which underlie thefundamentals of personal health, and acquaintshim with problems relating to personal health,conservation, heredity and eugenics. Health prin-ciples and practices are developed more directlywith respect to man. Biological facts and prin-ciples are presented which will enable the student

to understand why certain health laws and regu-lations are necessary for the community, state,and nation. Stress is laid on the balance in na-ture and the consequent necessity for conserva-tion; attention is directed to some of the currentpractices in this field. In the treatment of he-redity and eugenics, certain genetic material ispresented to enable the student td gain some con-cept of the mechanism of heredity. Eugenics ispresented from the point of view of such modernproblems as declining birth rate, foreign eugenicsprograms, the effect of war, and so on.

3) It points out some of the economic aspects ofbiology aside from those affecting personal health.More than the usual amount of space is devotedto the discussion of the sources of man 's foodsupply, clothing, shelter, drugs, and the like.These matters are treated from a world viewpoint,rather than from a purely local or national one.

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12 SCIENCE-IS

the rainfall, temperature and humidity, the maps are aninvaluable aid in the determination of types of clothingand equipment for our fighting forces stationed at distantand heretofore relatively unknown and uncharted regions.Looking into the future, Major W. F. Heald, of the

Climatological Unit of the Quartermaster Corps, predictsa very practical peacetime use of these maps when pleasuretravel is again in order. A glance at the current map,and no guesswork at all will be necessary for planningwhat to pack into a suitcase on any trip, no matter whereyou are going.

ARTIFICIAL SUNLIGHT AND JAUNDICEA "PILOT experiment" suggesting that artificial sun-

light may be the weapon for fighting the danger ofjaundice in persons who get human blood serum fortransfusions or protective inoculations is reported byDr. John W. Oliphant, Dr. Alexander G. Gilliam and Dr.Carl L. Larson, of the National Institute of Health.

The problem has caused national concern when morethan 28,000 soldiers developed jaundice following in-oculations against yellow fever. The Army solved itsproblem by switching to another type of anti-yellow fevervaccine which does not contain human blood serum. Sofar as known this new vaccine has not produced jaundice.Jaundice, perhaps of the same type, was the major dis-ease with which the Nazis have had to deal on the East-ern front, according to German medical reports that havereached this country.Even though our fighting men are not now in danger

of jaundice from vaccinations protecting them againstyellow fever, cases of the same ailment have been re-ported among civilians who were given convalescentserum for measles and mumps and following bloodtransfusions.

If the findings of the Public Health Service pilot ex-periment are confirmed by further tests, the danger ofjaundice following transfusions might be averted bypassing the blood or serum for the big transfusion banksin a thin stream through artificial sunlight. Forsmaller quantities of human serum, used to prepare vac-cines against disease, advantage might be taken of thefact that about two and a half months after a personhas had this jaundice, the disease-producing agent dis-appears from his blood.The cause of the disease is believed to be a virus, but

so far scientists have been unable to identify it, or togive the disease to laboratory animals. For the PublicHealth Service studies, 189 persons volunteered to getthe disease so that their blood could be used to learnmore about it. Most of them had only mild attacks andall recovered.

This serum jaundice is apparently not caught by con-tact with patients, although acute infectious jaundice is.Some believe that they are different diseases with differ-ent, unknown germ or virus causes. Others think thatthey are the same and that the differences are due to thedifference in getting the disease through serum inocula-tion or through contact with infected droplets on thepatient's breath.

ZI7PPLEMENT VOL. 99, No. 2563

ITEMSTHE discovery that a star, which greatly increased in

brightness a number of years ago because of an internalexplosion, has become egg-shaped may bring us closer tothe secret of the origin of our solar system. A cablereceived at the Harvard College Observatory from Dr. J.S. Paraskevopoulos, superintendent of the Southern Astro-nomical Station of the observatory, states that the oldnova in the southern constellation of Pictor, the Painter 'sEasel, is decidedly elongated. This nova brightened toa magnitude of 1.2 in 1925. Photographs made with the60-inch Rockefeller reflector at Bloemfontein, SouthAfrica, fail to show the usual haze which normally sur-rounds many of the novae. Revolutionary phenomenasimilar to those observed for the famous Nova Herculisof 1934 and Nova Persei of 1901 have apparently takenplace within Nova Pictoris. These explosive phenomenamay be linked with the evolution of planetary nebulae,but there is as yet no good evidence that they are con-nected with the evolution of planetary systems.APPARENT support for an old folk-belief that onions,

garlic and their strong-scented kin-vegetables are "goodfor what ails you" is offered by the reported discovery,by Professor B. P. Tokin, of the University of Tomsk,USSR, that their essential oils contain substances thatkill bacteria, protozoa, and even larger organisms likeyeast cells and the eggs of certain lower animals. Thereport is contained in a bulletin of the USSR Society forCultural Relations with Foreign Countries. ProfessorTokin has given the name " phytoncides " to the sub-stances he has isolated. Experimental use in hospitalsis now being made of these compounds, particularly in,the treatment of suppurative wounds.WATER can be used to conserve oil by means of a newly

developed procedure described by W. L. Horner and D..R. Snow, of the Barnsdall Oil Company, at the Chicago,meeting of the American Petroleum Institute. By in-jecting water into underground oil reservoirs as with-drawals are made, the original oil pressure is kept up to.par. Both newly discovered and partly depleted oil poolsmay use this method of maintaining underground pres-sure, providing that reservoir conditions are such that-artificial water drive can be applied. Water injection hasbeen used only on wells that are growing old; the methodhas hither not been considered suitable for pools in early-stages of production.

IF you want to know whether your favorite tooth pow-der or paste is wearing out your teeth, the National Bu-reau of Standards has a scientific test. The bureau nowhas developed a method to measure accurately the abrasiveeffects of tooth-cleaning preparations, and also the wear-ing effects on the teeth, if any, of various solutions usedas mouth washes. In measuring tooth-wear from abrasionor solution, the bureau uses an "indenter" of diamondhardness developed in its laboratories a few years ago.An extracted tooth is first polished and then scratchedwith it, making an indentation of known size. It is thenpolished mechanically with the dentifrice, or dissolved ina solution. The degree of disappearance of the marks,indicates the hardness of the tooth, or the wearing effect,of the polishing material or of the solution.

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CELLULOSE and CELLULOSEDERIVATIVESHigh Polymers, Vol. V.

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THE CHEMISTRY of LARGEMOLECULESFrontiers In Chemistry, VoL I.

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Report on recent developments in the chemistryand physicochemistry of Plastics and Elastics.

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THE CHEMICAL BACKGROUNDof ENGINE RESEARCHFrontiers in Chemistry, Vol. IL.

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14 SCIENCE-ADVERTISEMENTS VOL. 99, NO. 2563

SCIENCE-ADVERTISEMENTS

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SCIENCE-ADVERTISEMENTS VOL. 99, No. 2563

\ Bacto-AgarBacto-Agar is a purified Agar prepared from

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Bacto-Agar is distributed only for use inbacteriological culture media upon propercertification by the purchaser.,

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18 SCIENCE-ADVERTISEMENTS VOL. 99, No. 2563

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SCIENCE-ADVERTISEMENTS VOL. 99, No. 2563

How Americans Are Kept in Fighting TrimOOn some South Pacific island,in Africa, or on our northernbattlefronts ... wherever there

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a vital part of military preventive medicine. Throughthe microscope the Medical Corps knows of the ene-

mies . . . disease and infection . . . that lurk behindevery battleline.That is why, in the Bausch & Lomb plant, you will

still find microscopes being made . . . thousands ofthem . . . for microscopes have become an essentialto American fighting forces as have the gunfire con-

trol instruments, binoculars and aerial photographic

lenses which Bausch & Lomb also manufactures.Microscopes are typical of the many Bausch &

Lomb optical instruments that are performing vitalwar duty on the home front . . . in the industrial re-search and control that speed the production of thetools of Victory ... and in the medical and scientificresearch that will make it a better world to whichthese boys will return. Here again optical science isseeing it through.

For Bausch & Lomb Instruments essential to

Victory-priorities govern delivery schedules.

BAUSCH & LOMBOPTICAL CO. * ROCHESTER, N. Y.

ESTABLISHED 1853

AN AMERICAN SCIENTIFIC INSTITUTION PRODUCING OPTICAL GLASS AND INSTRUMENTSFOR MILITARY USE, EDUCATION, RESEARCH, INDUSTRY AND EYESIGHT CORRECTION

20

FERAY1,14 CEC-DETSMNS2

"WRATTEN LIGHT FILTERS"A Book ofi

THERE ARE more than 100 fil-ters in the series of Wratten lightfilters. They are designed foruse in general monochrome andcolor still photography, cinema-tography, and special scientif-ic fields-including astronomy,photometry, spectroscopy.Each Wratten Filter is made

to meet a rigid standard, and is supplied inthe form most convenient for its application.

ratten FiltersThe purpose of the book, WrattenLight Filters,-is to facilitate selec-tion of filters by providing com-plete spectrophotometric dataconcerning them.The 88-page Sixteenth Edi-

tion of this publication givestransmission curves and tablesfor all filters, as well as notes on

the use of filters for special purposes. It isavailable at dealers in photographic supplies.

EASTMAN KODAK COMPANYResearch Laboratories Rochester, N. Y.

A convenient and versatiletiming device which econo-mizes manpower and currentin controlling operation ofelectrical devices within itsrange, either in the plant orlaboratory.

* What the unit does: * The unit consists of:1. An electric clock with full size second hand.

1. Will start or stop any electrical device at a prede- 2. Indicating dials with individual knobs for setting de-termined time within a 12-hour interval. sired time operation.

2. Will start-and-stop or stop-and-start any electrical 3. Device which indicates "off," "on" or "set" positiondevice for any cycle of operation within a 12-hour of unit.period. 4. Mechanical interval timer.

5. Supplied with cords and plugs ready for convenient3. Equipped also with a spring wound interval timer connection to line and load.

which will sound a gong to indicate any interval 6. Will handle loads up to 1500 watts and will operatewithin 60 minutes. only on 110-115 volts, 60 cycle, A.C. current.

Its use in mechanically shutting off and staiting ovens during the night so that no delay is experienced inresuming operations in the morning is one of the simplest of the many useful functions of this device.

GBR-1001 ElectricTimeSwitchUnitComplete as described ............................................................................................ $35.00

THE EMIL GREINER C.161 SIXTH AVE. NEW YORK 13, N. Y.

SCIENCE-ADVERTISEMENTS 21FEBRUARY 11, 1944

22 SCIENCE-ADVERTISEMENTS VoL. 99, No. 2563

arget for Tonight"In the "Ready Rooms" of aircraft

carriers, in flight quarters at aviationland bases, in classrooms for main-tenance instruction courses, projectioninstruments are performing vital serv-ices in the war of today.

Of the various types of Spencer pro-jectors suitable for these tasks, theVA Delineascope has been especiallyuseful since -it is capable of projectingslides or opaque material, such as

photographs, charts, maps or draw-ings.

Sp encer LENS COMPANYBUFFALO, NEW YORK

SCIENTIFIC INSTRUMENT DIVISION OFAMERICAN OPTICAL COMPANY

22 SCIENCE-ADVERTISEMENTS VOL. 99, No. 2563