METEOROLOGY THEORETICAL AND APPLIED...meteorology, or for NavyV-12 courses in synoptic and dynamic meteorology. Many meteorological topics are treated from a fresh point of view. Amongthem

JAUR 8 94SINEAVRIEET

.-E.

I

METEOROLOGYTHEORETICAL AND APPLIED

By E. WENDELL HEWSON, Meteorologist, Mete-orological Service of Canada, and RICHMOND W.LONGLEY, Instructor in Meteorology, Head Office of

the Meteorological Service of Canada

This book presents basic theory and practice for the first time in one volume: It offers a simple treatmentof theoretical meteorology from elementary principles, and a discussion of synoptic meteorology. The twoparts are independent units, but nevertheless the treatment is integrated into a consistent whole. Crossreferences throughout the book are frequent.

The development is intended for those without an extensive background in mathematics and physics.Practically all equations are derived in the book. The material is suited for use in the first course inmeteorology, or for Navy V-12 courses in synoptic and dynamic meteorology.

Many meteorological topics are treated from a fresh point of view. Among them are the equations ofmotion, divergence and convergence, and frontogenesis and frontolysis. The book contains a chapter onmeteorological statistics; no other textbook offers this material. Chapters on climatology, instruments,map analysis and forecasting, and the relation of meteorology to human activities (subjects usually notall included in meteorological textbooks) are given.

The content of the book is based on experience gained during the past four or five years in teachingmeteorology, both theoretical and applied, to students in the University of Toronto, and more recentlyto technical personnel being trained by the Meteorological Service of Canada to cooperate with theR.C.A.F. in their training program.

CONTENTS: Observational Facts on the Atmosphere. PART I. THEORETICAL METEOROLOGY.Statics of the Atmosphere. Thermodynamics of Dry Air. Thermodynamics of Moist Air. Radiationof the Atmosphere. Atmospheric Motions under Balanced Forces. Frontal Surfaces. General Kine-matics and Dynamics of Air Motions. Turbulence. Statistical Analysis of Meteorological Data.PART II. APPNIED METEOROLOGY. Meteorological Instruments and Observations. The Gen-eral Circulation over the Earth. Temperature and Humidity in the Atmosphere. Stability and In-stability. Characteristic Properties of Different Air Masses. Cyclones and Anticyclones. Winds.Condensation and Precipitation. Formation and Dissipation. Clouds. Icing on Aircraft. Thun-derstorms. Climatology. Map Analysi and Forecasting Procedure. Meteorology Applied to Various]Human Activities. Appendix. Answers to Problems and Exercises. Index.

Published January 1944 468 pages Illustrated 5Y2 by 8M $4.75

JOHN WILEY & SONS, INC., 440-4TH AVE.,NEWYORK 16, N.Y.

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JANUARY 28, 1944 SCIENCE-ADVERTISEMENTS 9

SCIENCE-SUPPLEMENT VOL. 99, No. 2561

SCIENCE NEWSScience Service, Washington, D. C.

TITANTHAT the atmosphere of the planet Saturn 's largest

satellite, Titan, consists of methane or marsh gas andpossibly of ammonia has been discovered by Professor G.P. Kuiper, of the MeDonald Observatory of the Univer-sities of Chicago and Texas, as a result of successfullyphotographing its spectra. The Titan thus becomes theonly moon in the solar system known to have an ob-servable atmosphere.

This information is being transmitted by the Harvardclearing house to astronomers all over the world, as ithas an important bearing on problems concerning theatmospheres of all planets and their moons as well as

on the origin of the solar system.Several decades ago, observations indicated that Titan,

which is larger than the earth 's moon in both size andmass, had an atmosphere, but the difficulty of gettingsatisfactory spectra prevented study of the constitutionof such an atmosphere, if it really existed.Now Dr. Kuiper 's observations prove the existence of

the atmosphere and show that it must have abundantquantities of methane, which is usually called marsh gas

and is composed of one atom of carbon combined withfour of hydrogen. Its atomic weight is about 16, whilethat of ammonia, composed of one molecule of nitrogenand three of hydrogen, is about 17. It is the relativeheaviness of the atoms of these gases, when comparedwith hydrogen and helium, which enable them to cling toa moon of rather small surface gravity.Of great significance to astronomers is the fact that

Titan 's atmosphere appears to be similar to that ofSaturn itself. This may indicate a common origin forthe two bodies and also a similar constitution. However,Titan has a density about three and a half times that ofwater, whereas Saturn itself is lighter than water, theonly planet for which that is true. Saturn's low densityis explained by assuming it to be composed largely ofhydrogen. Atmospheres of methane and ammonia forboth Jupiter and Saturn add to the evidence supportingthis belief, and the finding of an atmosphere containinglarge amounts of hydrogen around Titan is further evi-dence along the same lines.-CHARLEs A. FEDERER, JR.

INDIANS OF THE MISSISSIPPI VALLEYAND THE EAST COAST OF MEXICO

THAT early Indians of the lower Mississippi Valley mayhave had direct connections with Indians on the east coastof Mexico, was stated by Dr. William Duncan Strong,director of the Ethnographic Board of Smithsonian Insti-tution, in an address before the Washington Academy ofSciences.

Pottery unearthed in both areas, in excavations directedby Dr. Gordon Eckholm, of the American Museum ofNatural History, is decorated with similar patterns ofbroad, grooved, incised lines. However, Dr. Strongpointed out, as the pottery found in Mexico dates backapproximately to 300 A.D. and that found in the United

States is placed at approximately 1000 A.D., it indicatesan 800-mile, 700-year migration of the Indians from Tam-pico, Mexico, to Louisiana. Most of the other significantMexican evidence of this relationship has long since de-cayed in the humid Mexican climate.The oldest Indian culture yet unearthed in Chile and

the coast of Peru-a simple fishing population which pre-

ceded the agricultural and horticultural civilizations-wasalso described by Dr. Strong. Fishhooks, bowls cut fromlava, barbed harpoons with stone points finely flaked bypressure, and coarse percussion-flaked stone tools made bybanging one stone against another to rough-shape theinstrument, remain to tell of the customs of this prehis-toric people. Junius Bird, of the American Museum ofNatural History, with Dr. Strong, brought this evidenceto light in the course of a year of intensive excavation."The great vistas in time and space revealed by the

present program of intensive research and excavationsmake it abundantly clear that the field of Middle andSouth American archeology is rapidly ripening, with a

promise of rich scientific harvest. It has always been a

field of superlative prehistoric interest, but only recentlyhas scientific work been envisaged on sufficiently broadand clean-cut lines to give definite promise of more sweep-

ing and valid culture-historical results," Dr. Strong pre-

dicted. "There seems little doubt that when the blightof the present war is removed this type of research workwill surge forward in all the American republics."

DISCOVERY OF A METEORITEA FOIJR-POUND meteorite has been discovered quite by

accident in a farmhouse yard in the northern part ofCowley County, Kansas. While serving as field represen-

tative for an oil company, H. H. Nininger, of the Ameri-can Meteorite Laboratory, found the stony specimen."While pumping a drink, I was, as always, scanning

the premises for odd-looking stones," Mr. Niningerreports in the current issue of Popular Astronomy."Under some plum bushes a few steps away I noticed a

rusty-looking chunk of rock about the size of my two fistsand at once decided that it needed investigation. Istepped over and picked up the rock, which was evidentlya badly weathered stony meteorite (an aerolite). "

Students of meteorites seldom have the good fortuneto stumble upon a meteorite in the field. This specimenrepresents a completely new find. No other meteorite hasbeen reported from any point nearer than 50 miles, and

the stone is recognized as belonging to a different fall

from those.Meteorites are classified roughly as stone and iron.

Iron specimens are more numerous -in museums because

they are more easily identified. Many more stones than

irons, however, have been seen to fall.

A GIANT-GRAINED HYBRID WHEATA GIANT-GRAINED hybrid wheat, with individual kernels

almost three times the weight of ordinary wheat grains,

10

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/l1geeflmZck1-6i~~ to teachers who are look-ing for a brief text in introductory physics atthe freshman level . .

White, Manning, Weber and Cornett's

PRACTICAL PHYSICSBy MARSH W. WHITE, Editor, KENNETH V. MANNING, ROBERT L. WEBER

The Pennsylvania State Collegeand R. ORIN CORNETTHarvard University

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365 pages, 6 x 9, 240 illustrations. Textbook edition, $2.50Here is an unusually timely text that meets an urgent need created under wartime conditions bystreamlined courses, shortened hours, and special service-group and adult training programs.Practical Physics has got off to a good start with over a score of adoptions that include the followingrepresentative institutions:

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JANuARY 28, 1944 11

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12

is one of the agricultural novelties which Soviet scientistsare preparing to carry back into western Russia as soon

as it has been cleared of Nazis. A cablegram receivedhere from the Soviet Scientists' Anti-Fascist Committeein Moscow adds that the new grain variety is also highlyresistant to practically all known fungus diseases ofwheat.The hybrid was orginated by Academician Anton

Zhebrak, member of the Belorussian Academy of Sciencesand professor of genetics at the Timiriazev Academy.He was working on his breeding experiments in the WhiteRussian city of Minsk when Hitler 's invasion was

launched, and carried his priceless propagation stock withhim as he left the burning streets behind. Now he isready to carry the descendants of those grains home fromexile, for further tests in their ancestral soil.

Academician Zhebrak's hybrid is a cross between the

standard hard or macaroni wheat known botanically as

Triticum durum and a recently discovered wheat speciesfrom the Caucasian highlands, called Triticum timopheevi.He has patriotically given it the name Soviet wheat, or

Triticum sovieticum.It is from the timopheevi wheat that the new hybrid

apparently derives its extreme resistance to fungus at-tacks. The same species has been introduced into breed-ing practice in the United States; of no economic valueby itself, it is prized for the contributions it makes inhybrid combinations.

Academician Zhebrak has also produced a hybrid be-tween the timopheevi species and common wheat (Trit-icum vulgare), which has progressed to the stage oflarge-scale field tests.

Both these hybrids are of the type which geneticistscall amphiploid. This means that the full number ofheredity-bearing chromosomes in the cells of both parentsare added together in the offspring, instead of beinghalved and the half-numbers then added. This increasedchromosome number often gives the resulting hybrids con-

siderable advantages such as increased size and greatervigor.The chromosome number for timopheevi wheat is 28,

for durum wheat the number is also 28, and for common

wheat it is 42. The timopheevi hybrid with common wheatthus has 70 chromosomes per cell, while the new Sovietwheat has 56.

ITEMS

NOVAE may owe their sudden flash of brilliance to theunion of the small dense cores of Cepheid stars, thosevariables of the heavens which increase and decrease in

brightness with clock-like regularity, according to a

theory developed by two British astronomers. The two

center cores whirl around each other within a large, tenu-ous atmosphere, which cloaks the cores so that the star

does not appear double. The cores get closer and closer

together until finally they unite into a single body. At

this point some of the stellar material may be thrown out

into space in an attempt of the star to restore its stabil-

ity, is reported by Dr. B. A. Lyttleton and. F. Hoyle of

the Monthly Notices of the Royal Astronomical Society.As the dense center cores unite, the main body of the star

VoL 99, No. 2561

may be torn away and the extremely hot surfaces under-neath be exposed. The star would therefore shine for a

time with much greater brilliance than its real surfacetemperature warranted. Novae would be just anotherstage in the development of these Cepheid variable stars,according to the authors, who think it possible for a starto flare up in brightness enough to be called a nova more

than once in its lifetime.

HIGH-OCTANE fuels such as are used in aircraft are not

suitable for ordinary automobiles. These fuels producetremendous pressure, and any automobile engine whichcould be developed to use them effectively would be tooexpensive, too heavy and too noisy. This is the opinionexpressed by C. B. Veal, of the Coordinating ResearchCouncil, Inc., New York, at the Detroit meeting of theSociety of Automotive Engineers. Even if designersshould produce an automobile engine capable of satis-factory operation with high-octane fuels, petroleum re-

finers would be forced to adopt expensive and uneconomi-cal refining methods, he stated. "Production of thesefuels consumes special chemicals at costs prohibitive inpeacetime," he added, "and greatly reduces the yieldof fuel per barrel of crude oil."

The man with the wrench holds the responsibility forthe service life of assembled machine parts, deelared J.0. Almen, of the General Motors Corporation at the same

meeting. " Just how much he tightens a nut, bolt or studdetermines the ultimate working life of the assembly..'He is "held to be a factor 16 times more important thandesign, metallurgy, or processing." "Good design andmaterials, heat-treatments, and superior manufacturingprocesses all are desirable," Mr. Almen said, "but thefatigue strength of highly loaded bolts, studs, and nutsfinally is determined by the man with the wrench-andhow little, or much, he applies that tool in the tighteningprocedure." Tests show, according to the speaker, thatif the initial tension on a bolt is increased from 1,420pounds to 8,420 pounds, fatigue durability goes up from5,960 stress cycles to more than 5,000,000. When a nutis tightened against reasonably rigid abutments to pro-

duce in the bolt a tension equal to or greater than theworking tension load, the speaker stated, practically no

stress change takes place and the bolt 's operating strengthapproaches its static strength.

TRADITIONAL hog-scalding to remove the hair in

butchering may soon be " out," replaced by a new scien-

tific method. In the new process porkers are plasticizedand peeled. The dead hog is submerged in a tank of

liquid plastic, then pulled out coated with the sticky stuff.

When properly cooled, the plastic is stripped off, takingall the hair with it. The process is quick, clean, thoroughand economical. The plastic used is a resin chemical.

After being used on one hog it is remelted and used

again and again. Bristles, whiskers, stubble and hairs

are removed from the liquid before it is re-used. Theyare just as suitable for commercial uses as if they had

been removed by the old scalding-scraping method. The

new chemical shaving method, and the resin chemical

used, were developed by the Hercules Powder Company.

SCIENCE-SUPPLEMENT

JANuARY 28, 1944 SCIENCE-ADVERTISEMENTS

New Interscience BooksCELLULOSE and CELLULOSE LUMINESCENCE of LIQUIDSDERIVATIVES and SOLIDSHigh Polymers, Vol. V. By P. Pringsheim, University of Chicago,* Edited by Emil Ott, Director of Research, Chicago, Ill. and M. Vogel, San Francisco,

Hercules Powder Company, Wilmington, Calif.Del. An attempt to explain, from the physicist's point

The book is the well-designed cooperative effort of of view, the nature and causes of luminescence anda number of experts in science and industry, under the experimental technique of studying lumines-the determined guidance of Dr. Ott, to present an cence. It surveys all inorganic and organic lumi-authoritative scientific picture of the cellulose field, nescent substances.with emphasis on the chemistry and physics of 6x9 200 pages 72 ill. $4.00cellulose and its derivatives.

6x9 1200 pages 72 ill. $15.00MAGNETOCHEMISTRY

THE CHEMISTRY of LARGE * ByP. W. Selwood, Northwestern University,MOLECULES Evanston, Ill.Frontiers In Chemistry, Vol. I First American monograph of the field of mag-

netochemistry. The author has given a compre-* Edited by R. E. Burk, The Standard Oil hensive and critical survey of the extensive litera-

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Report on recent developments in the chemistry 6x9 300 pages 80 ill. $5.00and physicochemistry of Plastics and Elastics.

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JANUARY 28, 1944 SCIENCE-ADVERTISEMENTS

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