PHASE TRANSFORMATIONS IN SOLIDSEdited by R. SMOLUCHOWSKI, Carnegie Institute of Technology, J. E. MAYER,University of Chicago, and W. A. WEYL, The Pennsylvania State College. Thisimportant new book is made up of papers (and the interesting discussions arousedby these papers) presented at a symposium held at Cornell University in 1948.Since scientists from different fields-physics, chemistry, ceramics, crystallog-raphy, metallurgy, mineralogy, etc.-have interchanged and correlated their in-finitely varied knowledge and experience on the phenomenon of phase trans-formation here, this book gives the first systematized, comprehensive treatmentof this subject. 1951. 660 pages. $9.50.

PATHOLOGY IN FOREST PRACTICESecond Edition by Dow VAWTER BAXTER, University of Michigan. This bookpresents the "inside story" of the origin, nature, and causes of diseases in treesand forests throughout the United States and tde continent. It tells how tocheck, regulate and control pests and diseases that destroy or limit the usefulnessof trees and their prodscts. Thoroughly backed up by the author's many yearsof teaching, research, and field experience here and abroad, this new editioncouples the latest scientific developments with sound, tested principles and tech-niques of forest disease and control. 1951. Approx. 574 pages. Prob. $10.00.

TENSOR ANALYSIS: Theory and ApplicationsBy I. S. SOKOLNIKOFF, University of California at Los Angeles. A broad treat-ment that develops tensor theory and then applies it to Geometry, Mechanics,Relativity, Elasticity, and Fluid Dynamics. Written by a man whose familiaritywith applied mathematics extends over a period of 25 years, the book's accuracyand care in exposition, selection of illustrative material, and usefulness as areference, make it the outstanding work on the subject. The latest volume inWiley's APPLIED MATHEMATICS SERIES. 1951. Approx. 362 pages. Prob. $6.00.

FLUORINE AND ITS COMPOUNDSBy R. N. HASZELDINE and A. G. SHARPE, University of Cambridge. Writtenfor the non-specialist, this book presents a compact and well-integrated intro-duction to fluorine chemistry. The history and occurrence, preparation, and the"physical and chemical properties of fluorine and its compounds are covered sys-tematically and thoroughly. This is one of METHUEN'S MONOGRAPHS ON CHEM-ICAL SUBJECTS. 19 5 1. In press.

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October 19, 1t151 11

HOTEL RESERVATIONS

118th AAAS MEETINGPhiladelphia, December 26-31, 1951

The list of hotels and the reservation coupon below are for your convenience in making your hotelvoom reservation in Philadelphia. Please send your application, not to any hotel directly, but to theAAAS Housing Bureau in Philadelphia and thereby avoid delay and confusion. The experienced HousingBureau will make assignments promptly; a confirmation will be sent vou in two weeks or less. Share a

room with a colleague if you wish to keep down expenses. Mail your application now to secure your

first choice of desired accommodations.

HOTELS AND RATES PER DAYHotel*

ADELPHIA*BARCLAYBELLEVUE-STRATFORD*BENJAMIN FRANKLIN*DRAKEESSEXJOHN BARTRAM*PENN SHERATONRITZ-CARLTON*ROBERT MORRISST. JAMESSYLVANIA*WARWICK

Cots added to a room are $2.50 ea

Single Double Twin-Bedded$5.00-$6.00 $7.50-$10.50 $10.00-$12.50

$ 8.00-$12.00$4.50-$6.00 $8.00-$10.00 $ 9.00-$12.00$5.00-$7.50 $8.00-$10.50 $11.00-$13.00

$6.00 $ 7.00 $ 9.00$4.75-$5.00 $6.00-$ 8.50 $ 9.00-$10.00$3.25-$4.50 $5.00-$ 8.00 $ 7.00-$ 9.00$5.00-$7.50 $7.50-$10.00 $ 8.00-$10.50$7.00-$7.50 $11.00-$12.00$4.50-$5.00 $7.00-$ 8.00 $ 8.00$4.00-$5.50 $6.00-$ 8.00 $ 6.50-$ 9.00

$ 9.00-$11.00$ 9.00-$12.00

ch; dormitory style rooms (for 5 or more) are $3.50 per person.

Suites$25.00-535.00$14.00-$25.00$20.00-$30.00

$18.00$15.00

$12.00-$15.00

$18.00$22.00-$24.00

* Hotels starred have sessions in their public rooms. For a list of the headquarters of each participating society and section,please see Association Affairs, Science, August 24, or The Scientific Monthly, September.

.------ THIS IS YOUR HOTEL RESERVATION COUPON . -AAAS Housing BureauArchitects Building (lst Floor)Philadelphia 3, Pa.

Date of Application ................

Please reserve the following accommodations for the 118 th Meeting of the AAAS:

TYPE OF ACCOMMODATION DESIRED

. . . Single Room (s)

. . . Double Room (s)

Desired Rate. Maximum Rate .........

Desired Rate. Maximum Rate ......... Number in Party ........

...Twin-Bedded Room(s) Desired Rate ......... Maximum Rate.

Desired Rate ........ Maximum Rate Sharing this room will be:

........... (Enumerate persons here and attach list giving name and address of each person, including yourself)

CHOICE OF HOTEL,

First Choice .. ..... Second Choice .Third Choice......... .

DATE OF ARRIVAL ................ DEPARTURE DATE

(These m-ust be indicated)

NAME ............................ .........................(Please print;o.typ)

ADDRESS ............................................................................................(Street) (City and Zone) (State)

Mail this now to the Housing Bureau. Rooms will be assigned and confirmed in order of receipt of reservation.

... Suite(s)

I '- SCIENCF.;; V-01. .114

REGISTER NOWfor the Philadelphia Meeting of the AAAS

AVOID CONGESTION AND DELAYGET YOUR GENERAL PROGRAM

BY FIRST CLASS MAIL - EARLY IN DECEMBER

Registration in advance of arrival at the 118th Annual Meeting of theAAAS in Philadelphia, December 26-31, 1951, has several striking advantages:

1. You avoid congestion and delay at Registration Desks at time of arrival.All indications point to a large attendance since all of the Association'seighteen sections and subsections, and more than forty societies, have ex-cellent programs, and, in addition to paper-reading sessions, there will bethe important symposia, conferences, and addresses for which an AAASMeeting is noted.

2. You receive the General Program early in December in ample time, un-hurriedly, to decide among the events and the sessions that you particularlywish to attend.

3. Your name will be in the Visible Directory the first hour of the first day ofthe meetings, since it will be posted in Washington as soon as received.(Hotel address can be added later, if necessary.)

4. Advance Registrants have the same privileges of receiving a map anddirectory of points of interest in Philadelphia, literature, radio broadcasttickets, etc. At the convenience of Advance Registrants, these will be dis-tributed from the Main Registration in the Municipal Auditorium-thelocation of the full-scale Annual Exposition of Science and Industry, theVisible Directory, the AAAS Science Theatre, and the Biologists' Smoker.

To insure its prompt receipt, the General Program will be sent by first class mailDecember 1-6, 1951-which last is also the closing date for Advance Registration.

.---------THIS IS YOUR ADVANCE REGISTRATION COUPON - .--

1. Advance Registration Fee (the extra quarter covers part of the first class postage) enclosed:O $2.25 AAAS Member (check one) E] $2.25 College StudentEI $2.25 Wife (or Husband) of Registrant O $3.25 Nonmember of AAAS

2. FULL NAME (Dr., Miss, etc.) .........................................................(Please print or typewrite) (Last) (First) (Initial)

3. ACADEMIC, PROFESSIONAL, ORBUSINESS CONNECTION ...........................................................

4. OFFICE OR HOME ADDRESS .......................................................(For reeipt of Program and Badge)

5. YOUR FIELD OF INTEREST .........................................................

6. CONVENTION ADDRESS ............................................................(If not known now may be added later)

7. DATE OF ARRIVAL .................... DATE OF DEPARTURE.

Please mail this Coupon and your check or money order for the fee, $2.25 or $3.25, toAMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE

1515 Massachusetts Avenue, N.W., Washington 5, D. C.

October 19,- 19,51 113

Ouujtanc/nq macmint an 00k

Erwin B. Kelsey & Harold G. Dietrich

Fundamentals of Semi-MicroQualitative Analysis, Rev. Ed.

This revision represents a complete rewriting of the original text. Boththe theoretical and analytical sections have been rewritten. Proceduresfor analytical groups are presented in the form of tabular outlines.With each analytical group there is included a discussion of the specifictheoretical concepts applied in the group. Published in September-$4.00

Wendell M. Latimer & Joel H. Hildebrand

Reference Book

of Inorganic Chemistry, 3rd EdIn the new third edition recent investigations in the field are included,and the entire book is brought up-to-date generally with the presenta-tion and interpretation of the new material. The subjects of molecularstructure and thermodynamics are emphasized heavily, and includeexplanations of oxidation potentials, equilibrium constants and free en-

ergies. Ready in NovemberE. Howard Smart

Advanced Dynamics, if two vols.Volume I, Dynamics of a Particle, gives a complete discussion of recti-linear motion with acceleration directed towards and away from a fixedpoint; oscillating particles; simple harmonic motion with unresistedand damped vibration; impulsive forces applied to problems of impact.Volume II, Dynamics of a Solid Body, embraces a complete discussionof d'Alembert's principle and the equations of motion in two and threedimensions; Lagranges' equations and generalized coordinates; the mo-

tion of a top; Hamilton's equations and general theorems of impulses.Published in August-$12.00 the set

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October 19, 1951

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Civilian DefenseBy IRVING L. JANIS. The Rand Series. 280 pages, $5.00.

A comprehensive analysis of all existing reports on the psychological aspects of air war with the psy-chological effects of atomic bombing and conventional air attacks described in detail. The book con-sists of three main sections: 1) Reactions at Hiroshima and Nagasaki, 2) Effects of Air War, and3) Psychological Aspects of Civilian Defense.

PULP AND PAPER MANUFACTURE. Volume 2. Preparation of Stock for Paper MakingPrepared under the Direction of the Joint Textbook Committee of the Paper Industry of theUnited States and Canada. Editor-in-chief: J. N. STEPHENSON. Ready in October

This volume, the second of a new series of four, is based on Volumes III, IV, and V of a formerseries known as The Manufacture of Pulp and Paper. New developments have necessitated a re-integration of old material with-new-methods and procedures. Several new processes for the prepara-tion of papermaking stocks have been developed. These developments are described and an addi-tional chapter is included which contains sections on Semichemical Pulping and The MechanicalPulping of Pretreated Wood.

PRINCIPLES OF QUANTUM MECHANICSBy W. V. HOUSTON, Rice Institute. International Series in Pure and Applied Physics. Ready inDecember.

Provides the student with an understanding of the uses of quantum mechanics in the various fieldsof physics. Contains a deductive presentation of the wave mechanics form of quantum mechanicsand includes a general outline of the basic theory developed from two fundamental postulates, fol-lowed by a series of illustrative applications.

FIELD CROPS. New 2nd EditionBy H. C. RATHER; and C. M. HARRISON, Michigan State College. McGraw-Hill Publications inthe Agrciultural Sciences. Ready in November.

An excellent revision of this very successful text, the second edition covers the major field crops, theirdistribution, planting, management, harvesting and use. Also specific chapters deal with such broadareas as soil conservation, land use, crop improvement, and forage and pasture management, with par-ticular emphasis on management for livestock use.

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