SCIENCE-ADVERTISEMENTS

Hegner's Essig's

COLLEGEZOOLOGY

Well known as the outstanding text inits field this general survey for stu-dents who will not take advanced workis here happily combined with detailedinstruction sufficient for those whowill. In the organization of material,the author's purpose has been to trainstudents in the methods of scientificinvestigation. 5th Ed. $3.75

BRUNER'S LABORATORY DIREC-TIONS IN COLLEGE ZOOLOGYcorresponds with Hegner 's CollegeZoology but is sufficiently detailedand comprehensive for use with stand-ard'texts other than Hegner's. 3rdEd. $1.75

COLLEGEENTOMOLOGY

This foundation text in entomologycovers the history of the 33 ordersof insects, emphasizing those specieswhich, because of their historical back-ground, economic importance, or un-usual and interesting appearance,should be known to all students ofnatural history. Full lists of fami-lies, keys for separating the variouscategories of insects, and abundantillustrations, largely original, are in-cluded. $5.00

Huettner'sWalter'sBIOLOGY OF THEVERTEBRATES

This text has long been a favorite withstudents and teachers alike for its ex-ceptionally readable, interesting style;its completeness and clear organiza-tion of content; and its wealth of well-drawn, helpful illustrations. It pre-sents all the materials which are use-ful in college courses on the verte-brates or on comparative anatomy.2nd Ed. $4.00

FUNDAMENTALSOF COMPARATIVEEMBRYOLOGY OFTHE VERTEBRATES

A modern approach and interpreta-tion, thorough scientific accuracy, andoriginal copperplate illustrations, allexceptionally clear, detailed, and ac-curate, make this an unusually finetext for students of embryology.$4.50

Vol. 103, No. 26638A

SCIENCE-ADVERTISEMENTS

PHYSICAL CHEMISTRY FOR PREMEDICAL STUDENTSBy JOHN PAGE AMSDEN, Dartmouth College. International Chemical Series. 295 pages, 54 x84. $3.50

Written especially for a one-semester course for premedi- out problems illustrate each topic treated. Throughoutcal students, this text includes only those portions of ele- the text the Brdnsted concept of acids and bases has beenmentary physical chemistry which will be of value to the used consistently.medical student in his later professional work. Worked

WAVE PROPAGATION IN PERIODIC STRUCTURES. Electric Filtersand Crystal Lattices

By LfON BRILLOUIN, Columbia University. International Series in Pure and Applied Physics.247 pages, 5i x 84, 137 illustrations. $3.50

Incorporates a variety of problems linked by a common tures of various kinds, which invariably, whether they aremathematical background, extending from electrical en- electric lines or crystal lattices, behave like band-passgineering to electromagnetism and wave mechanics of the filters.spinning electron. All problems deal with periodic struc-

PIEZOELECTRICITY. An Introduction to the Theory and Application of ElectromechanicalPhenomena in Crystals

By WALTER G. CADY, Wesleyan University. International Series in Pure and Applied Physics.In press-ready in February

A comprehensive treatise covering the entire field of mental principles, the author deals with all phases ofpiezoelectricity, including related areas of elasticity, di- piezoelectric theory and its principal applications.electrics, optics, and magnetism. Beginning with funda-

COUNSELING WITH RETURNED SERVICEMENBy CARL R. ROGERS, University of Chicago, and JOHN L. WALLEN, Black Mountain College.165 pages, 5i x 8. $1.60

Following the "client centered" method of counseling, attitude of the nondirective counselor, development andthe authors aim to assist in the training of the many in- growth of the client, methods, the counseling process individuals who are undertaking to counsel returned service- action, etc. Many actual cases are included.men, servicewomen, and others. The book discusses the

SEX AND THE SOCIAL ORDERBy GEORGENE H. SEWARD, Simmons College. McGraw-Hill Publications in Psychology. 286pages, 54 x 8. $3.50

Presents a comparative study of the part played by sex of life is shown to be associated with a shift in the bal-in representative social organizations from fish ta mnan. ance between biological and social determiners of sexSex is consistently viewed within the framework of the behavior.society as a whole. Progress from lower to higher forms

ELECTRONS IN ACTIONBy JAMES STOKLEY, author of Science Remakes the World. 309 pages, 51 x 81, 38 pages, ofphotographs and sketches. $3.00

A clear, relatively nontechnical account of what electrons and describes their applications in the many fields ofare, where they come from, and how they are put to work. electronics. Frequency modulation and television areThe author explains the characteristics of electron tubes examined carefully.

Send for copies on approval

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January 11, 1946 9

SCIENCE-ADVERTISEMENTS

A Selected List of

WILEY BOOKS IN 7tt4aeMaFor the Integrated Course I

COLLEGE ALGEBRA ANDTRIGONOMETRY

By FREDERIC H. MILLER, The Cooper UnionSchool of Engineering

A basic integrated treatment for a first course incollege mathematics, preparatory to calculus, thistextbook lays a good foundation for subsequentstudy of more advanced mathematics.

324 pages; 51 by 8X; 1945; $S.00

A FIRST YEAR OF COLLEGEMATHEMATICS

By HENRY J. MILES, University of Illinois

A textbook for a two-semester freshman course in

college mathematics. Includes college algebra,plane trigonometry, plane and solid analyticgeometry.

607 pages; 51 by 81; 1941; $3.00

BASIC MATHEMATICS FORENGINEERS

By PAUL G. ANDRES, HUGH J. MISER and HAIMREINGOLD; all at Illinois Institute of Technology

Covers those branches of mathematics with whichthe student of science and engineering must befamiliar, and offers sufficient background so thatthe student may go on to the study of calculus.Basic geometric principles and formulas are givenin the appendix.726 pages, with answers; 51 by 81; 1944; $4.00

-For Separate Courses-COLLEGE ALGEBRA

By H. P. PETTIT and P. LUTEYN; both at Mar-quette University. Second edition; 247 pages;51 by 81; 1941; $1.90

COLLEGE ALGEBRABy LOUIS J. ROUSE, University of Michigan.Second edition; 462 pages; 5f by 71; 1939; $2.25

ANALYTIC GEOMETRYBy EDWARD S. SMITH, MEYER SALKOVER andHOWARD K. JUSTICE; all at the University ofCincinnati. 298 pages; 6 by 94; 1943; $2.50

TRIGONOMETRYBy HOWARD K. HUGHES and GLEN T. MILLER;both at Purdue University. With tables: 268pages; 51 by 81; 1939; $2.00

PLANE AND SPHERICALTRIGONOMETRY

Bv HARVEY A. SIMMONS, Northwestern Univer-sity. With tables: 504 pages; 51 by 81; 1945;$3.00. Without tables: 387 pages; 51 by 81;$2.25

CALCULUSBy EDWARD S. SMITH, MEYER SALKOVER andHOWARD K. JUSTICE. 558 pages; 6 by 94;1938; $3.25

CALCULUSBy FREDERIC H. MILLER. 419 pages; 6 by 94;1939; $3.00

PARTIAL DIFFERENTIALEQUATIONS

By FREDERIC H. MILLER. 259 pages; 6 by 94;1941; $3.00

DIFFERENTIAL EQUATIONSBy HARRY W. REDDICK, New York University.245 pages; 54 by 81; 1943; $2.50

DIFFERENTIAL EQUATIONSBy HENRY B. PHILLIPS, Massachusetts Instituteof Technology. Third edition; 125 pages; 51by 81; 1934; $1.75

WILEY'S TRIGONOMETRIC TABLESSecond edition; 117 pages; 6 by 94; 1945; $1.00

JOHN WILEY & SONS, Inc., 440-4th Ave., New York 16, N. Y.

10 Vol. 103, No. 2663

SCIENCE-ADVERTISEMENTS

Steam Heat only.

6t 4t.o REFLUX STILLfor pure distillation

THE Castle Reflux Still produces approximately10 gallons of pyrogen-free distillate per hour, witha greater degree of purity than any other standardapparatus or process. It is completely automaticand is constructed with evaporator for quick, easycleaning when necessary.

The Castle Reflux Principle permits partial purifi-cation of the water even before it gets to the evap-orating chamber. Overflow deconcentrating tubeprevents concentration of solids in evaporatorwhich has 27-inch height and baffle design to pre-vent contamination of condenser by foaming orsplashing. It operates on the Reflux Principle inwhich the primary condenser returns one quarterof the vapor . . . particularly the larger particles. . . to the evaporator and only the finest vaporpasses over to the secondary condenser producingthe final condensate.For further details of the Castle Reflux Still,write: Wilmot Castle Co., 1212 University Ave.,Rochester 7, N. Y.

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11January 11, 1946

SCIENCE-ADVERTISEMENTS Vol. 103, No. 2663

A NEW A.A.A.S. SYMPOSIUM

CANCER9

This volume, comprising the papers and discussions presented at theAAAS-Gibson Island Conference on Cancer in the summer of 1944, records inlarge measure the status of cancer research at the time the conference was held.The conference extended through five days for the presentation of papers andfor formal and informal discussions, in the light of which the original contri-butions were revised and recorded discussions were edited. A total of 95 spe-cialists contributed to the conference, of whom 79 were present in person.

The program of the conference consisted of five groups of papers as follows:I. The Virus Approach (five principal papers and four supplementary

notes, 107 pp.)IT. Carcinogenesis (seven principal papers, 62 pp.)

III. Enzymes (five principal papers, 8.3 pp.)IV. Diet (two principal papers and one note, 38 pp.)V. Chemotherapy (four principal papers and two notes, 43 pp.)

x + 3 3 3 pp., 7 '2 x 10 '/2, illustrated, clothbound, documetted,December, 1945

MAMMARY TUMORS IN MICE9

This A. A. A. S. Symposium was prepared by members of the staff of theNational Cancer Institute and published in March, 1945. In it attention isconcentrated upon one particular type of cancer in one particular species, in thebelief that such an approach avoids the dangers of drawing conclusions byanalogy from one type of malignant tumor to another and from one species toanother, while revealing the magnitude and complexity of the cancer problemas a whole.

viii + 223 pp., 7 Y2 x 10 /2, illustrated, clothbound, documented,March, 1945

Prices, cash orders (postage prepaid)

Cancer Mammary Both BooksTumtors9

To members of A. A. A. S........ $4.00 $3.50 $6.25

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The latest development in Refrigerated Centrifuges, the InternationalModel PR-i offers the laboratory analyst practically all of the advan- *ltages of the larger permanent type installations plus portability. Cen-trifuge and compressor are combined in one attractive cabinet mountedon casters, and both units are operated from a single cord and plugwhich can be connected to the ordinary lighting circuit.

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Notice to Subscribers and ContributorsCommunications relative to articles offered for publication

should be addressed to Editor, Massachusetts and NebraskaAvenues, Washington 16, D. C.

Communications relative to advertising should be ad-dressed to Theo. J. Christensen, Massachusetts and NebraskaAvenues, Washington 16, D. C.

Communications relative to membership In the Associationand to all matters of business of the Association should beaddressed to the Permanent Secretary, A.A.A.S., SmithsonianInstitution Building, Washington 25, D. C.

Communications relative to subscriptions from nonmembersshould be directed to The Science Press, North Queen St. andMcGovern Ave., Lancaster, Pa.

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Bacto-AgarBacto-Agar is a purified Agar prepared from

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14 Vol. 103, No. 2663

January 11, 1946 SCIENCE-ADVERTISEMENTS

I N T H E M A R K E T P L A C ERATES to be paid in advance. Regular setting 10¢ a word, minimum charge $2.00 each; count 8 worda if a box address is usedDisplay, 3 inches maximum $8.80 per column inch. No discounts or commissions.SEND advertisements with remittance to the ADVERTISING DEPARTMENT, American Association for the Advancement of Science,AMERICAN UNIVERSITY, MASSACHUSETTS AND NEBRASKA AVENUES, WASHINGTON 16, D. C. Correct remittancemust accompany instructions and copy and advertisement will be Published in sequence of completed orders.

REPLIES to box number advertisements should bC sent to the Advertising Department for forwarding.

BOOKSELLERS

Wanted to purchase-Scientific Periodicals, sets and runs,Poreign-Domestic. Entire libraries and smaller collections.WALTER J. JOHNSON, 125 East 23rd Street, New York 10,N. 1

Journals, Periodlials, Serial Publications-Sets, runs andsingle volumes hought and sold. Entire libraries purchased.J. S. CANNER COMPANY, Boston 15, Mass.

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Opportunities Wanted-Young man expecting early dischargeis available for position in public health or bacteriology; B.A.(major in biological sciences and education); M.S., (biology);MPH ; five years' teaching experience; three years, head ofdepartment of hygiene and sanitation where he also directedclinical laboratory department; several years with the pnhlichealth service as sanitarian; for further information, pleasewrite BURNEICE LARSON, Director, The Medical Bureau, Palm-olive Building, Chicago 11.

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Opportunities Available-(a) Physicist for research appoint-ment with large manufacturing industrial company; shouldhave background in manufacturing industry and definiteinterest in mathematical formulation and solution of physicalproblems in heat, mechanics and electricty; university medi-cal center; East. (h) Pharmacologist or biochemist withtherapeutic background for appointment with laboratories ofexperimental therapeutics conducted under university aus-pices. (c) Bacteriologist; research department, large teach-ing hospital; recent graduate eligible. (d) Research assistantin microbiology; part-time appointment with western uni-versity; must be interested and qualified to work towardPh.D. degree. (e) Pharmacologist or chemist to serve asliaison officer between research and manufacturing depart-ments of large pharmaceutical company; competent ad-ministrator required; $8,000 S1-1 Medical Bureau (BURNEICELARSON, Director) Palnmolive Building, Chicago 11.

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