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VoL. 83, No. 2159

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CHEMISTRY

Organic ChemistryBy JAMES BRYANT CONANT, Harvard University

A new REVISED EDITION of Conant's text for the one-semester course in organic chem-istry was published March 10th. Considerable new material has been added to sections onbiochemistry, an excellent review of basic principles has been incorporated in the chapteron the structure and synthesis of the simpler compounds, and all material has been broughtup to date. The pedagogy has also been revised to follow that of Conant's larger text. $2.60

Textbook of QuantitativeInorganic ChemistryBy I. M. KOLTHOFF and E. B. SANDELL, University of Minnesota

A complete text, including elementary, advanced, and practical work in quantitative analy-sis, typographically arranged to be readily adaptable for use in either the first- or second-year course. The material is presented under four main sections: Gravimetric Analysis,Volumetric Analysis, Physico-Chemical Methods, and Analysis of Complex Materials.Proper balance between theoretical and practical work has been kept throughout. PublishedApril 25th. $4.50

General ChemistryBy HARRY N. HOLMES, Oberlin College

The THIRD EDITION REVISED of Holmes' standard text for first-year college coursesin chemistry will be published this summer. A great deal of new material has been addedon all new advances in theory and in the practical application of chemical theory, makingthe book up-to-the-minute in every respect. The revised edition of the LABORATORYMANUAL will be ready in September.

Physical CehemistryBy FRANK H. MACDOUGALL, University of Minnesota

An exceptionally high standard of scientific thoroughness characterizes this new text forintroductory courses in physical chemistry. Unusually complete material is given on topicsof basic importance such as thermodynamics and atomic structure. To be published in June.

$4.25 (probable)MACMILLAN NEW YORK

MAY 15, 1936 SCIENCE-ADVERTISEMENTS 3

4 SCIENCE-ADVERTISEMENTS VOL. 83, No. 2159

Catalytic Reactions atHigh Temperatures

and PressuresBy VLADIMIR N. IPATIEFF, Northwestern University

A description of the methods of investigation used in the study of catalytic reactions underhigh pressures, and an account of the development of catalysis in organic chemistry. Theauthor is a world authority on catalysis, and much of his own work is discussed in thisbook, including his research of the past three years which is published here for the firsttime. To be published in June. $7.50 (probable)

PHYSICS

A Textbook of PhysicsBy CHARLES A. CULVER, Carleton College

A new text for first-year college courses, especially prepared for the engineering studentor the student who intends to specialize in science. It is unusually comprehensive, includ-ing many of the facts and theories of modern physics as well as thorough treatment offundamentals. To be published in June. $4.50 (probable)

An Elementary Survey of

Modern PhysicsBy GORDON FERRIE HULL, Dartmouth College

This book presents comprehensive material for a course in modern physics suitable eitherfor students who have had only one year of general physics or for more advanced students.The material is arranged so that the more difficult mathematics may be omitted in classesof less advanced students. The text has been successfully used in mimeograph form atDartmouth for several years. To be published in June. $4.75 (probable)

MACMILLAN NEW YORK

'VOL. 83, No. 21594 SCIENCE-ADVERTISEMENTS

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BIOLOGY

College ZoologyBy ROBERT W. HEGNER, Johns Hopkins University

The FOURTH EDITION, REVISED, of Hegner's well-known text will be published May26th. It will contain new material on the grasshopper and the frog, a new chapter on therelations of the protozoa to man, a new chapter on parasitism in animals, and a great manynew illustrations. The general plan of the volume remains the same. $3.50 (probable)

Outlines of

General ZQologyBy HORATIO HACKETT NEWMAN, University of Chicago

The THIRD EDITION, REVISED, will be published in June. This new edition broadensthe concept of biology by showing living organisms not only in their relation to each otherbut in their relation to the whole cosmic order. There are new chapters on Life in ItsCosmic Setting, The Energy Traffic in Animals and Plants, The Beginnings of Life andthe Origin of New Life Today, Variety, Unity and Abundance of Living Organisms. Allmaterial has been brought up to date, and summaries added at the ends of chapters. $3.50(probable). A LABORATORY MANUAL, by Katherine McClure Roehl and H. H. New-man to accompany this text will be published at the same time. $1.00 (probable)

Foundations of BiologyBy LORANDE Loss WOODRUFF, Yale University

The FIFTH EDITION, REVISED, was published April 25th. About a hundred newfigures have been added. There are two new chapters giving a synoptic view of the repre-sentatives of the plant and animal kingdoms, and much new material throughout. This isa text which has been very widely used for many years, popular with students and teachersalike for its clear, interesting presentation and excellent organization of material. $3.50

MACMLLA NE YOR

MAY 15, 193ff 5

NEW YORKMACMILLAN

6 SINEAVRIEETVO.8,N.25

Manual of BiologyBy GEORGE A. BAITSELL, Yale University

The FIFTH EDITION REVISED of Baitsell's well-known Manual will be published May19th. Intended primarily to accompany Woodruff's text, this Manual is also sufficientlycomplete in itself to be used with any other standard text on general biology.

$2.60 (probable)

General BiologyBy JAMES WATT MAVOR, Union College

A new text for the introductory course in general biology dealing with the Nature ofLife, Plant Life, Invertebrates, Vertebrates, and Principles. Approximately one-fifth of thetext is devoted to Botany. The invertebrate types are discussed chiefly from the point of viewof evolution. The final section, devoted to Principles discusses such matters as the develop-ment of the individual, the physical basis of heredity, the theory of evolution, etc. $4.00(probable). A LABORATORY MANUAL, by Professor Mavor and Leonard B. Clark, toaccompany this text will be ready in September.

Two new volumes in the Experimental Biology Monographs

NeuroembryologyAN EXPERIMENTAL STUDY

By SAMUEL R. DETWILER, Columbia University

A full discussion of the results of investigations dealing with the dynamics of developmentin the nervous system by methods of experimental surgery on the embryo. To be publishedAMay 26th. $3.75 (probable)

The Eggs of MammalsBy GREGORY PINcus, Harvard University

A presentation of experimental investigations dealing with the behavior of mammalian eggsduring various stages of their development in the ovaries, fallopian tubes, and uterus,including an account of recently developed techniques for the experimental manipulationof living ova. To be published in the fall.

MACMILLAN NEW YORK~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

6 SCIENCE-ADVERTISEMENTS VoL. 83, No. 2159

NEW YORK IMACMILLAN

VOL. 83, No. 2159

being that the virtual image of the object shall lie atthe axis of rotation.

The arrangements shown in Figs. la and lb havebeen used with good success in simple air-driven micro-scope centrifuges.2

E. G. PICKELSUNIvERsPrY OF VIRGINIA

A PIEZOELECTRIC ULTRAMICROMETER

THE ultramicrometer is an instrument for the mea-

surement of linear displacementrs smaller than thoseaccessible by the methods of optical interferometry,which are limited by the wave-length of light. Whid-dington,' using two oscillating electrical circuits tunedso as to produce an audible beat-tone, was able toextend the sensitivity of measurement to a value some-

what smaller than 10- cm. This was accomplishedby the measurement of the variation of beat-tonebetween the two circuits, this variation being a measure

of the change of frequency produced in one of themby the change of capacity of its condenser caused byalteration of distance between condenser plates. An-other method consists in exciting a resonant circuitby an oscillator at such a frequency that the response

of the resonant circuit is most sensitive to a variationof exciting frequency; the amplitude of current inthe resonant circuit will then register a change causedby a shift in frequency, as that produced by a changein distance apart of the plates of a condenser in theexciting circuit. This method, with especially designedcircuits, has been developed at the Bell telephoneLaboratories for the measurement of displacement ofmicrophone contacts,2 the sensitivity being such that a

displacement of a condenser plate by 10-8 cm couldproduce a galvanometer deflection of one inch.A piezoelectric quartz plate provided with suitable

electrodes is the equivalent of a resonant electricalcircuit, and the properties of such plates have beenstudied extensively by W. G. Cady3 and by D. W.Dye.4 When the plate electrodes are connected tothe terminals of the condenser in a simple resonantcircuit which is being excited by an external source ofvariable frequency, the response curve (e.g., effectivecurrent plotted against frequency) of the circuit ismodified by a deep cleft or crevasse at the natural fre-quency of the quartz plate. This crevasse is extraordi-narily narrow and its sides are so steep that if theoperating frequency of the exciting circuit be set so

as to correspond to a point of the steepest slope, a

2 Beams and Pickels, Rev. Sci. Inst., 6: 299, 1935.1 R. Whiddington, Phil. Mag., 40: 634-639, 1920.2 J. R. Haynes, Bell Laboratories Record, 13: 337-342,

1935.3 W. G. Cady, Proc. I. R. E., 10: 83-114, 1922.4 D. W. Dye, Proc. Phys. Soc. Lond., 38: 399-458, 1926.

small change of the exciting frequency will cause acorrespondingly large change in the oscillatory currentin the resonant circuit connected with the quartz, anda thermogalvanometer in this circuit will register acorresponding change of reading. In general, changesof frequency much too small to be detected by usualmethods will cause a measurable change in the gal-vanometer reading.

Using a quartz plate of 600 KC resonant frequency,a frequency change of one sixtieth of a cycle per sec-ond may be detected, corresponding to a frequencychange of about three parts in one hundred million.Such a change in frequency may be caused by a minutechange in the distance between the plates of a con-denser in the exciting circuit. The practical limits towhich measurements may be pushed depend upon thestability of frequency of the exciting eircuit and uponthe freedom from minute mechanical disturbances ofthe small condenser, the displacement of one plate ofwhich is to be measured. To test the method a mi-crometer condenser has been constructed so that eachplate is attached to a separate support clamped to aheavy steel rod. Adjustments are provided for makingthe plates parallel and for making relatively largevariations of plate distance by means of a micrometerscrew. Additional known micro-variations of platedistance are made by applying small known bendingforces to the steel rod. A variable condenser in paral-lel is provided so as to operate the micrometer con-denser at any desired plate distance and thus to securea wide range of sensitivities. In the experimentswhich have so far been carried out displacements of10-s cm have been measured to a few per cent., thoughno special precautions have been taken against me-ehanical disturbances. By taking such precautions itis expected that displacements of 10-10 cm may bemeasured. The attainment of a sensitivity of thisorder should open a new avenue of approach to anumber of important problems.

J. C. HUBBARDTHE JOHNS HOPKINS UNIVERSITY

BOOKS RECEIVEDDUGGAR, BENJAMIN M., Editor. Biological Effects of

Radiation. Vol. I, 686 pp. Vol. II, 665 pp. McGraw-Hill.

IZQUIERDO, J. JOAQUIN. La Fisiologia en Mexico. Pp.vi + 358. Illustrated. Author, Mexico, D.F.

KOLTHOFT, I. M. and E. B. SANDELL. Textbook of Quan-titative Inorganic Analysis. Pp. xv + 749. 113 figures.Macmillan. $4.50.

MCCRADY, EDWARD. Reason and Revelation: Argumentfor the Truth of Revealed Religion Based Solely uponthe Evidences of Science and Philosophy. Pp. 411.Wm. B. Eerdmans, Grand Rapids, Michigan.

SAUNDERS, FREDERICK A. A Survey of Physics for Col-lege Students. Revised edition. Pp. viii+679. Illus-trated. Henry Holt. $3.75.

472 SCIENCE

MA 5 96SINEAVRIEET

- ~~JUST PUBLISHEDEames-MORPHOLOGY OF VASCULAR PLANTS.

Lower Groups-Psilophytales to FilicalesBy ARTHUR J. EAMES, Professor of Botany, Cornell University. McGraw-Hill Pub-lications in the Agricultural and Botanical Sciences. 420 pages, $4.00

This advanced textbook covers the morphology and life histories of vascular plants. Emphasisis placed upon broad comparative studie& of the various groups with the development of a naturalclassification and of phylogenetic relationships as a goal. Facts are presented as a basis for thedetermination of morphological principles and for the building up of a natural classification.Classification is built up as group is compared with group, and a complete classification isattained only at the end of the book. Much attention is given to recently acquired information,particularly that concerning fossil groups.

Hill, Overholts and Popp-BOTANY. A Textbook forCollegesBy J. BEN HILL, LEE 0. OVERHOLTS and HENRY W. POPP, Department of Botany,The Pennsylvania State College. McGraw-Hill Publications in the Agriculturaland Botanical Sciences. 655 pages, $4.00

Throughout the first part of this new book, the physiology of an organ is considered in connec-tion with its structure in general. In Part II, devoted entirely to a consideration of the differentgroups of plants, the authors give an adequate and balanced survey of the plant kingdom with-out undue emphasis on any one group. Clear, complete explanations without oversimplificationare a most important feature of the book. Special attention is given to growth and metabolismand stress is laid on the physiological importance of color. The book is up to date, presenting thelatest developments on the life history of the lily and the life history of the pine.

BIOLOGICAL EFFECTS OF RADIATION. Mechanismand Measurement of Radiation, Applications in Biology,Photochemical Reactions, Effects of Radiant Energy onOrganisms and Organic Products

Edited by BENJAMIN M. DUGGAR, Professor of Plant Physiology and Applied Bot-any, University of Wisconsin. With contributions by 46 specialists. Preparedunder the auspices of the Committee on Radiation, Division of Biology and Agri-culture, National Research Council. Two volumes (not sold separately), 1342pages, $12.00

Presents a fundamental survey of the effects.of radiant energy on the processes, development,heredity, and more important products of plants and animals. Each of the forty-three chapters isthe work of one or more specialists in the subject it covers.

Send for copies on approval

Aldwych House, London, W.C.2McGRAW-HILL BOOK COMPANY, INC.

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