VOL. 88, No. 2295

tained a small amount of the nitrogen isotope. Bothexperiments must be taken as proof that at least asmall amount of creatine and amino acids can beformed with ammonia as a nitrogen donor and thatdietary ammonia may be utilized for this process.

In another experiment the fate of one dietary aminoacid, tyrosine, was followed in a full-grown adult ratkept in nitrogen equilibrium on a normal diet, theprotein of which consisted of casein. To this wasadded an amount of isotopic dl-tyrosine correspondingto only 14.4 mg nitrogen addition per dav. The ani-mal was kept on this diet for ten days. It excreted anamount of total nitrogen equivalent to that in the totaldiet, but about half of the isotope was retained by thetissues. The retention must have been accompaniedby the liberation (for excretion) of an equivalentamount of nitrogen. The liver and the remaining car-cass were worked up separately to locate the isotope.Almost all of it was recovered in the proteins, whilethe non-protein-nitrogen revealed only traces. Bothliver and carcass proteins were hydrolyzed, and puretyrosine was isolated. The samples contained a highconcentration of isotope, indicating an extensive depo-sition of the dietary tyrosine in the body proteins.However, the isotope content in tyrosine accounted foronly a-bout one quarter of the total isotope content inthe proteins. Amino acids, other than tyrosine, mustthus have taken up nitrogen originally present intyrosine. This could be proved. The following otheramino acids were -isolated: arginine, lysine, histidineand the mixture of the dicarboxylic acids, glutamic andaspartic acid. With the exception of lysine, all ofthem contained a significant amount of isotopic nitro-gen. As the dicarboxylic acids contain only 1 nitrogenatom per molecule, the position in the molecule of thenewly introduced nitrogen is certain. The position ofthe isotope in the arginine and histidine, both of whichcontain more than one nitrogen atom per molecule, hadto be investigated. The arginine isolated was split intoornithine and urea. All the isotope was found in ureamoiety, while the ornithine contained normal nitrogen.The a-amino group of histidine was removed by coni-verting the amino acid into imidazole lactic acid. Thelatter contained normal nitrogen; all the isotope musthave been in the a-amino group of the originalhistidine.

The experiment shows that in a normal full-grownand healthy animal, kept on a normal diet, the nitrogenof at least one of the dietary amino acids, tyrosine, isonly partly excreted in the urine, while the rest is re-tained in She protein of the animal, with a correspond-ing excretion of tissue nitrogen. Only a fraction ofthe nitrogen deposited remains attached to the originalcarbon chain of the amino acid, with which it wasgiven, the bulk being utilized in the formation of some

other amino acids. Degradation of some of the iso-lated amino acids has given some insight into theprocesses which must have been responsible for theirformation:

(1) The dicarboxylic acids containing only onenitrogen atom were either newly synthesized from sub-stances with different carbon chains or underwentdeamination followed by amination of the remainingketo acid. Whichever of these two processes was re-sponsible, its occurrence was not suppressed by theabundance of these substances in the dietary protein,casein.

(2) Arginine was formed from ornithine, probablyin the course of urea formation, according to the theoryof Krebs.

(3) Histidine was successively deaminated and re-aminated at the a-carbon atom alone.

(4) Ornithine and lysine are apparently not subjectto such processes.

All these reactions had occurred with constituents ofthe proteins of a normal animal and reveal an extensivechemical activity of its proteins.

RUDOLF SCHOENHEIMERD. RITTENBERGG. L. FOSTERALBERT S. KESTONS. RATNER

DEPARTMENT OF BIOLOGICAL CHEMISTRY,COLUMBIA UNIVERSITY

BOOKS RECEIVEDBrooklyn Botanic Garden Record; Vol. XXVII, No. 3,

July, 1938; Contents: Botanic Gardens of the World;Materials for a History. Second edition. Pp. 151-406. Brooklyn Institute of Arts and Sciences. $2.50.

DEN HARTOG, J. P., and others. Contributions to theMechanics of Solids Dedicated to Stephen Timoshenkoby his Friends on the Occasion of his Sixtieth BirthdayAnniversary. Pp. vii + 277. Illustrated. Macmillan.$5.00.

FAIRCHILD, DAVID. The World Was my Garden; Travelsof a Plant Explorer. Pp. xiv + 494. Illustrated.Scribner 's. $3.75.

Fondation Universitaire. Statistiques des Dipl6m6s del'Enseignement Sup6rieur en Belgique. Pp. 99. Uni-versitaire Stichting, Brussels.

GIDDENS, PAUL H. The Birth of the Oil Industry. Pp.xxxix + 216. Illustrated. Macmillan. $3.00.

LICHTIG, IGNAZ. Die Entstehung des Lebens; DurchStetige Sch6pfung. Pp. xx + 371. 4 figures. Noord-Hollandsche Uitgevers Maatschappij, Amsterdam. Gul-den 6.

NEEDHAM, JOSEPH, and WALTER PAGEL, Editors. Back-ground to Modern Science; Ten Lectures at CambridgeArranged by the History of Science Committee, 1936.Pp. xii ± 243. Macmillan. $2.00.

RITTER, WILLIAM E. The California Woodpecker and I.Pp. xiii + 340. 28 figures. University of CaliforniaPress. $3.50.

TOLMAN, RICHARD C. The Principles of Statistical Me-chanics. Pp. xix + 660. Oxford University Press.$9.00.

ULICH HERMANN. Kurzes Lehrbuch der PhysikalischenChemie. Pp. xv + 315. 79 figures. Steinkopff, Dres-den. RM 12.

600 SCIENCE

DECEMBER 23, 1938 SCIENCE-ADVERTISEMENTS

The University of Chicago Press recommends:

19

In the Biological SciencesANIMALS WITHOUTBACKBONES

An Introduction to the InvertebratesBy Ralph BuchsbaumFollowing an informal lecture style, this book offers a newapproach to the field of the invertebrates, a lucid literarystyle and a collection of illustrations unmatched in anyother invertebrate text (over 250 drawings and 300 gra-vure photographs). Stresses principles rather than puremorphology, each group of animals presenting a zoblogicalprinciple. Published November 29. $3.75THE MACHINERY OF THE BODYBy Anton J. Carlson and Victor Johnson132 colleges and universities have adopted this text. "In-teresting and concisely written, simplified yet accurate . . .have succeeded more completely than any others in bring-ing together in close integration all the physiologic relation-ships."-Journal of the A. M. A. $4.00

THE STORY OF THEPLANT KINGDOM

By Merle C. CoulterPhylogenetic sequence is the basis for presenting the essen-tials of botany for college freshmen, or as foundation formore advanced study. ". . . clear, simple, straightfor-ward."-School Science and Mathematics. $2.50

MAN AND THE VERTEBRATESBy Alfred Sherwood Romer"The use of this book should revitalize the courses in verte-brate evolution and anatomy in many of our colleges."-William F. Hahnert, Ohio Wesleyan University. $3.00

HANDBOOK of HISTOLOGICALand CYTOLOGICAL TECHNIQUEBy R. R. Bensley and S. H. Bensley $2.00

In the Physical SciencesFROM GALILEO TOCOSMIC RAYS

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EXPLORING IN PHYSICSBy Reginald J. StephensonA manual, providing stimulating problems to supplementFrom Galileo to Cosmic Rays. Paper-bound. $1.00

DOWN TO EARTHBy Carey Croneis and William C. Krumbein"Eminently suitable for any introductory course in geologyin any institution . . . chances are excellent that it willprove to be an unusually satisfactory piece of equipmentfor the modern class room. . . Beneath, this lightness oftouch there is plenty of good solid geology."-Kirtley F.Mather, Science. $3.75

HIGHLIGHTS OF ASTRONOMYBy Walter BartkyPhenomena explained in a simple, clear and interesting man-ner. ". . . the first text that actually directs . . . stu-dent thinking outside the classroom."-Loren T. Caldwell,N. Illinois S. T. C. $2.50

A MATHEMATICIAN EXPLAINSBy Mayme I. Logsdon"This unusual book will be of interest to the teachers ofmathematics and science in the junior and senior highschools. Every high school, college, and public libraryshould be well stocked with it."-Dr. J. M. Kinney, SchoolScience and Mathematics. $1.75

Ask to see these books at A.A.A.S. meeting or write for examination copies to:

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PROGRESSIVE RELAXATION. By Edmund Jacobson, M.D.(Revised edition). Three new chapters develop original electrical methods to measure muscu-lar contractions, nervousness, and mental activities. "A valuable contribution to the field ofpsychological medicine and of interest to physicians in all fields of medicine and surgery."-Urologic and Cutaneous Review. $5.00

THE PRIMATE THALAMUS. By A. Earl Walker, M.D.95 illustrations. "It contains so much useful information that it should be read by everyoneseriously interested in neurology."-Archives of Neurology and Psychiatry. $3.00

AN INTRODUCTION TO THE STUDY OF STELLARSTRUCTURE. By S. Chandrasekhar. Treated as a deductive scientifictheory, the subject is developed from its foundations and includes chapters on thermodynamicsand its applications to astrophysics. Ready January. $10.00

Selected List of New 1938 McGRAW-HILL BOOKSCotton

AGRICULTURE

By EI. B. BROWN, Louisiana State University.Secontd edition. 592 pages, $5.00

Commercial Fruit and Vegetable ProductsBy W. V. CRUESS, University of California.Second edition. 791 pages, $6.00

Poultry HusbandryBy M. A. JULL, University of Maryland. Secondedition. 548 pages, $4.00

StarcraftASTRONOMY

By W. H. BARTON, Hayden Planetariumn, andJ. M. JOSEPH. 228 pages, $2.50

BIOLOGICAL SCIENCESAn Introduction to American Forestry

By S. W. ALLEN, University of Miclhigan. 402pages, $3.50

Forest PathologyBy J. S. BOYCE, Yale Univelrsity. 600 pages,$5.00

Physiological GeneticsBy RICHIARD GOLDSCIIMIDT, University of Cali-fornia. 375 pages, $4.00

An Introduction to BotanyBly A. W. HAUPT, Uniiversity of Califorilia atLos Anigeles. 396 pages, $3.00

Wood PreservationBy G. M. HUNT, U. S. Forest Products Labora-tory, anld G. A. GARRATT, Yale School of For-estry. 457 pages, $5.00

Plant PhysiologyBy N. A. MAXI-AOv. Edited by R. B. HARVEYand A. E. MURN EEK. Second edlition. 473pages, $4.50

Plant PhysiologyBy E. C. MILLER, Kansas State College. Secondteclition. 1139 pages, $7.50

Methods and Materials for Teaching Biological SciencesBy 1D. F. MILLER and G. W. B3LAYDER, Ollio State'University. 435 pages, $3.50

Textbook of General Physiology13y P. 11. MITCHELL, Brown University. Thtirdedition. 853 pages, $6.00. Manual, $1.50

Textbook of Comparative PhysiologyBy C. G. ROGERS, Oberlin College. Seconrd edi-tion. 698 pages, $5.50. Manual $1.5()

HeredityBy A. F. SHULL, Uniiversity of Michigan. Tltir-dedition. 442 pages, $3.50

Principles of GeneticsBy E. W. SINNOTT and L. C. DIJNN, ColuinbiaUniversity. l'7tir(d edlition. 410 pages, $3.50

Cryptogamic BotanyBy G. M. SMITH, Stanford University. Vol. I.Algae and Fungi. 545 pages, $4.00. Vol. 11.Bryophytes and Pteridoplhytes. 380 pages, $3.00

Plant EcologyBy J. E. WEAVER, University of Nebraska, anidF. E. CLEMENTS, Carnegie Institution of Wash-ington. Second edition. 601 pages, $5.00

General ZoologyBy H. L. WIEMAN, University of Cinciinnati.Third edition. 497 pages, $3.50

CHEMISTRYAND CHEMICAL ENGINEERINGSemi-micro Qualitative Analysis

By PAUL ARTHuR and 0. MN. SMrITH, OklahomiaA. & M. College. 198 pages, $2.00

Unit Processes in Organic SynthesisEdited by P. H. GROGGINS, U. S. Department ofAgriculture. Second edition. 769 pages, $6.00

Problems in Organic ChemistryB,y LE. IT.HUNTRESS, Massachlsetts Institute ofTechnology. 270 pages, $2.25

Laboratory Technique in Organic ChemistryBy A. A. MORTON, Massacl;usetts Institute ofTeclhlology. 243 pages, $2.50

Textbook of Inorganic Chemistry For CollegesBy J. F. NORRIS and R. C. YOIUNG, Massachu-setts Iilstitute of Techllology. Seconid e(lition.769 pages, $3.75

Theoretical and Descriptive Qualitative AnalysisBy J. H. REEDY, University of Illliiois. 477pages, $3.00

The Elements of Fractional DistillationBy C. S. ROBINSON and E. R. GILLILAND, 1\IS-sachla setts Institute of Technology. Th ird d(i-tion. 268 pages, $3.00

Fundamentals of Biochemistry with Laboratory ExperimentsBy C. L. A. SCHIlDT and F. W. ALLEN, Uiniver-sitv of Californiia. 388 pages, $3.00

General ChemistryPBy E. P. SCI1OCH and W. A. FELSING, Univ-er-sity of Texas. 524 pages, $3.25

Library Guide for the ChemistBy B,. A. SOULE, University of Mliehigan. 302p)ages, $2.75

Crystal ChemistryBy C. W. STILLWVELL. 431 pages, $4.50

An Introduction to ChemistryBy J. A. TIMMI, Yale Uni versity. T7liird eldition.568 pages, $3.50

Chemical Engineering EconomicsBy CHAPLIN TILER. 241 pages, $3.00

Calculations in Quantitative Chemical AnalysisBy J. A. WILKINSON, Iowa State College. Sec-on0d edilion. 154 pages, $1.75

20 SCIENCE-ADVERTISEMENTS VOL. 88, NO. 2295

Selected List of New 1938 McGRAW-HILL BOOKSGEOLOGY AND GEOGRAPHY

Quartz Family MineralsBy H. C. DAKE, F. L. FLEENER and B. H. WIL-SON. 304 pages, $2.50

Geology. Principles and ProcessesBy W. H. EMMONS, G. A. THIEL, C. R. STAUF-FER, University of Minnesota, and I. S. ALLISON,Or1egon State College. Second edition. 441pages, $3.75

Physiography of Eastern United StatesBy N. AM. FENNEMIAN, University of Cincinnati.714 pages, $6.50

Practical Oil GeologyBy DORSEY ITAGER, Consuilting Geologist andPetroleunm Engineer. Fifth edition. 466 pages,$4.00

General CartographyBy ERWIN RAISZ, Harvai-d University.pages, $4.00

Introductory Economic GeologyBy W. A. TARR, Uniiversity of Missouri.ond edlition. 645 pages, $5.00

GENERAL SCIENCEColor Photography for the Amateur

By KEITH HIENNEY, Editor, Electronics.pages, $3.50

Weather

367

See-

280

By GAYLE PICKWELL, San Jos6 State College.170 pages, $3.00

An Orientation in ScienceBy Eleven Members of tlhe University of Roch-ester Faculty. C. W. WATKEYS, Editor. 560pages, $3.50

MATHEMATICSTheory of Equations

By J. M. TIIO\rAS, Duke Uinivelrsity. 211 pages,$2.00

Elements of Statistical MethodByv A. E. WAUGH, Connecticut State College.381 pages, $3.50. Manual, $1.5C

PHYSICSPhysics for Technical Students

l-3y AV. B. ANDER.SON, Oregon State College.TIhird editiorn. 807 p)ages, $4.00

Principles of Electricity and ElectromagnetismBy G. P. ITARWIVELL, Unliv ersity of Peiiiisyl-vauia. 619 pages, $5.00

Kinetic Theory of GasesBy l'F. TI. KENNARD, Cornl-ell Uiiiversity. 483pages, $5.00

Electrical MeasurementsBy the late P. A. LAWS, Massachusetts Instituteof Technology. Second edition. 739 pages,$6.00

The Elements of PhysicsBy A. W. SMITH, Ohio State Uniiversity. Fourthedition. 790 pages, $3.75

Demonstration Experiments in PhysicsEdited by R. 'M. SUTTON, Haverford College.Pr epar ed under the Auspices of the AmericanAssociation of Physies Teachers. 545 pages,$4.50

PHARMACY AND MEDICAL SCIENCEQualitative Analysis for Students of Pharmacy and Medicine

By C. B. JORDAN and H. G. DEKAY, PurdUeIJniversity. Second edition. 178 pages, $2.50

Pharmaceutical TherapeuticsBy E. V. LYNN, Massachusetts College of Phar-nmacy. Second edition. 430 pages, $4.00

Medical EntomologyBy W. A. RILEY, Uni versity of Miinncsota, aind0. A. JOHANNSEN, Corniell University. Secondedition. 483 pages, $4.50

Pharmaceutical MathematicsB3y EDAWARD SPEASE, Western Beserve Uiiiver-sity. Second edition. 150 pages, $1.75

PSYCHOLOGYRecent Experiments in Psychology

B)y L. W. CRAFTS, T. C. SCHNEIRLA, E. E. ROB-INSON and R. W. GILBERT, New Yorli University.417 pages, $2.25

Psychology of MusicBy C. E. SEASHORE, Univ ersity of Iowa. 408pages, $4.00

Psychological Aspects of BusinessBy E. K. STRONG, JR., Staniford University.629 pages, $4.00

Psychological Factors in Marital HappinessBy L. M. TERMIAN, Stan1ford UnIiversity. 474pages, $4.00

Psychological Foundations of PersonalityB4y L. P. THORPE, UIniversity of Soutlherni Cali-fornia. 602 pages, $3.50

The Art and Science of MarriageBy E. B. TIETZ, Longviewv hTospital, Ciniiiniiati,an1d C. K. WEICHERT, University of Cincinnati.279 pages, $2.50

Psychology in Everyday LifeBy WV. C. VARNUEM, Los A'ngeles City College.444 pages, $2.75

-1'I

The McGraw-Hill booth at the A.A.A.S. Convention, in addition to the books listed above, willexhibit many others in such fields as economics, education, engineering, and the social sciences,

which were published in 1938.

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21DECEMBER 23, 1938 SCIENCE-ADVERTISEMENTS

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DECEMBER 23, 1938 SCIENCE-ADVERTISEMENTS 25

CONTRIBUTIONS TO THE

MECHANICSO-F SOLIDSJ29 articles by outstanding menin the field of applied mechanicsare published in this volume inhonor of the sixtieth birthday ofStephen Timoshenko

CONTENTS: 1. S. Timoshenko by Lessells. 2. On a ParticularBuckling Problem by Biezeno and Koch. 3. Tuned Pendulumsas Torsional Vibration Eliminators by Den Hartog. 4. On theApplication of Southwell's Method for the Analysis of BucklingTests by Donnell. 5. Recrystallization and Its Effect on theForgeability of Copper in the Single-Blow Drop Test by Ellis.6. Kritische Drehzahlgebiete der fliegend angeordneten Scheibeby Foeppl. 7. On Frictional Effects in Shrink Fits by Goodier.8. A Method of Calculating Grillage Beams by Hetenyi. 9.Fatigue Failure of RR. Axles and Stresses in Hollow Cylindersby Horger. 10. Analysis of Strain Measurements and PolarDiagrams for Plane Stress by Hovgaard. 11. Zur Elastiz.tats-theorie der anorthotropen Platten by Huber. 12. Effect of aFlexible First Story in a Building Located on Vibrating Groundby Jacobsen. 13. On the Mechanism of Dry Friction by Kare-litz. 14. Use of Orthogonal Functions in Structural Problemsby von Karman. 15. Dynamic Stability of Railway Trucks byLanger. 16. Differential Area Relations in the Plastic Statefor Uniaxial Stress by MacGregor. 17. Ueber den singularenPunkt zweiter Ordnung im ebenen Spannungsfeld by von Mises.18. The Influence of Time upon Creep by Nadai. 19. NaturalFrequencies of Torsional Vibration in Branched Systems byOrmondroyd. 20. Methods of Correlating Data from FatigueTests of Stress Concentration Specimens by Peterson. 21.Studien ueber die unelastische Formaenderung by Prandtl. 22.Plasticity and Creep in Machine Design by Soderberg. 23.Castigliano's Principles of Minimum Strain-Energy and the Con-ditions of Compatibility for Strain by Southwell. 24. Analysisof Plastic Strain in a Cubic Crystal by Taylor. 25. TransientTorques in Induction Motor Drives by Wahl. 26. Hamilton'sPrinciples and the Principle of Least Action in the Solution ofCreep Problems Involving Relaxation by Waters. 27. A Later-ally Loaded Clamped Square Plate with Large Deflection byWay. 28. Developments in Photoelasticity by Weibel. 29. AProblem of Elasticity Suggested by a Problem in Soil Mechanicsby Westergaard. $5.00

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Published This FallA COURSE OF STUDY IN CHEMI-CAL PRINCIPLES. Revised Edition.By Noyes and Sherrill. A thorough revisionof the standard text for engineering studentson physical. or theoretical chemistry. $5.00

THE STRUCTURE OF ECONOMICPLANTS. By Hayward. The first com-prehensive study of the structure and develop-mental anatomy of 16 important economicplants. $4.90

HOUSEHOLD PHYSICS. By Avery.Clear explanations of the basic principles ofphysics and a detailed study of their modernapplications in the household field. $3.50

THEORETICAL MECHANICS. ByCoe. An unusually thoroughgoing treatmentfrom the vectorial point of view. $5.00

BACTERIOLOGY. Fourth Edition. ByBuchanan. A revised, up-to-date edition ofone of the standard texts for students in gen-eral and household science. $3.50

LABORATORY MANUAL TO AC-COMPANY INTRODUCTORY GEN-ERAL CHEMISTRY. Revised Edition.By Dietrich and Kelsey. The manual forBrinkley's text revised to correspond with therevision of the text. $1.90

Coming in JanuaryTHE PHYLUM CHORDATA. By New-man. A comprehensive, very interestinglywritten text for the lecture part of coursesin vertebrate zoology. $3.75 (probable)

PHYSICO-CHEMICAL EXPERI-MENTS. By Livingston. Full directionsfor 41 well chosen and well worked out ex-periments, with an initial section on comput-ing methods and the theory of errors andmeasurements. $2.50 (probable)

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26 SCIENCE-ADVERTISEMENTS VoI.. 88, No. 2295

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ZEISS Dipping Refractoeeand industrial laboratories, food analysis, Shown wit/h Prism Inserted intoBeaker in Temperature Regus-

pharmaceutical and clinical institutions. lating Pan.

Meas. prism I nD = 1.325 -nD = 1.367 Meas. prism L6 nD = 1.5011-D = 1.5322" " L2 nD = 1.3642-nD = 1.3999 " " L7 nD = 1.5312-nD = 1.5631

" L3 nD = 1.3989-nD = 1.4360 " " L8 nD = 1.5621-nD = 1.5899" L4 nD = 1.4350.nD = 1.4678 " " L9 nD = 1.5889-nD = 1.6205"4(i L5 nD = 1.4668-nD = 1.5021 " " L10 nD = 1.6195-nD = 1.6470

Special prism Z nD = 1.331--nD = 1.372-for sugar tests

Catalog No. 165/V will be sent free upon request

CARL ZEISS, INC.485 Fifth Av e n ue 728 So. HiIl St reetN E W Y O R K L O S A N G E L E SJEi-

26 SCIENCE-ADVERTISEMENTS VoL. 88, No. 2295