Book ReviewsEncyclopedia of vocational guidance. (Vols. 1 & 2.)

Oscar J. Kaplan. (Ed.) New York: PhilosophicalLibrary, 1948. Pp. xxi+ 1422. $18.50.The editor of this most significant two-volume work

modestly states in the preface that "this book is encyclo-pedia in a relative sense; it does not pretend to cover ingreat detail all phases of the guidance field." Thoughthe statement is literally correct, the compilation is amonumental contribution to applied science. The mate-rial presented is concise, clear, pragmatic, and sufficientlycomprehensive to serve well those who are concerned withthe practical phases of vocational guidance and whomight well be confused by theoretical discussions of someof the unsettled areas of psychological science. Dr.Kaplan has assembled an imposing array of contributors,some 287 in number, representing many disciplines suchas education, economics, psychology, psychiatry, medicine,and statistical science. The more useful aptitude testprocedures are well presented, and the reference materialincludes sufficient data anent sources so that the articlescan be used as the starting point for further studies.Particularly interesting to those in the social sciencesare the contributions describing the postwar status ofvocational guidance in the Netherlands, Portugal, Switzer-land, Australia, and New Zealand.

The significant shifts in age distribution in our popula-tion structure and the growing problem of vocationalplacement of the aging and those with various handicapsfrom traumatic (war) injuries or chronic progressivediseases of later maturity make vocational guidance ofimmediate and urgent concern to millions of individuals.For professional counselors and personnel administrators,medical clinicians, ministers, nurses, educators, insuranceadministrators, the military forces, public health officials,veterans administration personnel, and even legislators,the work is very nearly a must. The multiple-disciplineapproach is a significant step forward in the applicationof science to social planning.The volumes are attractively bound but are unnecessar-

ily bulky because of the poor quality of the paper;future printings deserve a much better grade of material.The typography is good. The alphabetical encyclopediaarrangement of the contributions avoids the necessityof an index.

EDWARD J. STIEGLITZ1726 I Street, N.W., Washington, D. C.

Modern colloids: an introduction to the physical chemistryof large molecules and small particles. Robert B. Dean.New York-Toronto-London: D. Van Nostrand, 1948.Pp. xi + 303. (Illustrated.) $3.75.

This latest addition to the literature on colloid chemis-try in textbook form starts with a definition of whatcolloid science is, a discussion of types of colloids, anda list of sources for published information. The follow-ing chapters cover methods for determining size and shape

68

of colloidal particles, liquid surfaces and their character-istics, adsorption phenomena and their application inscience and industry, and high polymers, their synthesis,and properties. Special chapters are devoted to plastics,resins and rubber, carbohydrates and proteins, emulsionsand foams, hydrous oxides and silicates, and also to col-loidal ions and their electrokinetics and to lyophobiccolloids or suspensoids.The author deserves credit for writing a book to stimu-

late the interest in colloid chemistry in such diversifiedfields as chemistry, biology, medicine, and agriculture.The reviewer, a colloid chemist himself, feels, however,that the book covers far too much for an introduction tocolloid chemistry and that its organization is more apt toconfuse the reader than to enlighten him. In addition,it will give the reader who is not familiar with whatmodern colloid chemistry already stands for an entirelywrong impression. To offer some proof for this opinion,the following examples might suffice:The physics and chemistry of surfaces is not just an

intimate part of colloid science, but colloid science itself.The statement that nearly all of the properties oflyophobic colloids are due to the presence of impurities iscontrary to well-established facts.A more elaborate discussion of ultramicroscopes, their

construction, and application would be far more appro-priate than writing a eulogy of the electron microscope,which also has its limitations, particularly when studyinglyophilic colloids. Ultramicroscopy by incident light andits applications in research pertaining to lyogels is notmentioned. That solutions of proteins and other highpolymers show no Faraday-Tyndall effect is contrary tofact. In the chapter on liquid surfaces, the drop weight,drop number, and pendant drop methods are not men-

tioned. The statement that a rigid gel must have its solidcomponent extending continuously through the system andthat a thixotropic gel sets only when the particles asso-

ciate is contrary to experimental evidence. Finally, thediscussion of rubber latex is incomplete because it dis-regards the most basic colloidal phenomena.

ERNST A. HAUSERMassachusetts Institute of Technology

Scientific Book Register

BORING, EDWIN GARRIGUES, LANGFELD, HERBERT SIDNEY,and WELD, HARRY PORTER. (Eds.) Foundations ofpsychology. New York: John Wiley; London: Chap-man & Hall, 1948. Pp. xv + 632. (Illustrated.)$4.00.

MCLACHLAN, N. W. Modern operational calculus withapplications in technical mathematics. Cambridge,Engl.: at the Univ. Press; New York: Macmillan, 1948.Pp. xiv + 218. (Illustrated.) $5.00.

SUITS, C. G., HARRISON, GEORGE R., and JORDAN, Louis.(Eds.) Applied physics: electronics, optics, metal-lurgy. Boston: Atlantic-Little, Brown, 1948. Pp.xiii + 456. (Illustrated.) $6.00.

SCIENCE, July 16, 1948, Vol. 108

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company; East. (d) Laboratory man well trained in physiological.chemistry to head department in laboratories of 18-man group andhospital; department supervised by pathologist; staff of seven tech-nicians; research program involving chemistry of body in relationto blood-fluid balance; town of 35,000, Rocky Mountain state;around $4000. (e) Statistician to direct division of vital statistics.state department of health; $5100. (f) Psychologist for assistantprofessorship of mental hygiene- position deals with problems ofmental hygiene and related wori in general and educational psy-chology; state university; South. (g) Bacteriologist for positioninvolving virus research; pharmaceutical company; East. (h)Young man for fundamental and applied research in nutrition;duties include supervising work of others; Ph.D. or equivalencyin biochemistry or nutrition preferred; one of the country's lead-ing food manufacturing companies. S7-3, Medical Bureau (Bur-neice Larson, Director), Palmolive Building, Chicago 11. X

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AMERICAN INCUBATORSSelected by Leading Institutionsfor Virus and Laboratory WorkAmong the users are: Rockefeller

Foundation; New York City Dept. ofHealth; N. Y. State Dept. of Health;8ueens General Hospital. New Yorkity; National Institute of Health.

Bethesda, Md.; Sloan Kettering In-stitute, New York City; and many other famous institu-tions. The American is first choice, where uniform heatand humidity is required. There's a size to suit everyrequirement.Write fordescriptive AMERICAN-LINCOLN INCUBATOR CO.folderDept. AS 645 Somerset St., NEW BRUNSWICK. N. J.

XFoxGEOILOGISTS SSURVEWORSENG INECR5 6poe^ ff f~iEery oec A i5^ sc$t&f ~su

.e5as XPeM

~~~~~~..5 Joas=

ATTENTION ZOOLOGISTS: We wish to purchase the follow-ing preserved specimens: Paramecium aurelia; Pennaria medusae;nasutus soldiers of Termite; half-inch leeches; Cyclops with eggsacs; all stages of small ant; Taenia pisiformis; Dipylidiumcaninum; Necator americanus; Ancylostoma; Phthirius pubis;brook lampreys; Astrangia danae; Terebratulina vitrea; Teredo;small Octopi; Ciona; Molgula manhattensis; Hippocampus;Lingula; Laqueus californicus; human brains in formalin; Englishsparrows; alligators; division stages of Paramecium gaudatum.GENERAL BIOLOGICAL SUPPLY HOUSE, 761 East 69thPlace, Chicago 37, Illinois. X

HOLTZMAN RAT

Specializing in the Production of High Quality White Ratsfor Laboratory Use.

R. 4, MADISON 5, WISCONSIN PHONE GIFFORD 7188

17

1 1

ARNOLD STEAM STERILIZERS

Open Reservoir and Quick Steaming Base

Provide Constant Sterilization at 100 O.The open, visible reservoir in the ArnoldSterilizer is refilled without interruption of thesteaming process. Small apertures carry water

to quick steaming base and steam is providedin the sterilizing chamber at an unvaryingtemperature of 1000C.

Excessive steam is confined under a head to

provide a steam jacket which maintains uni-

form temperature within the chamber. Con-

densation is returned to reservoir.

Constructed of heavy polished copper, the

Arnold Sterilizer is available for gas or steam

heat. For full details, see your Castle dealer or

write: Wilmot Castle Company, 1212 Univer.-sity Ave., Rochester 7, N. Y.

ANNOUNCING AVAILABILITYof

TETRAZOLIUM SALTS

These new reagents for testing viability of seed':"have been synthesized and supplied to leading corn

growers since the summer of 1947.

2,3,5-Triphenyltetrazolium Chloride

2,3-Diphenyl-5-Methyl Tetrazolium Chloride

Forthcoming publication from this laboratory will announce theapplication of these reagents and other tetrazolium salts to thestudy of neoplasms, detection of sugars and aldehydes.

The Synthetical Laboratories5556 Ardmore AvenueChicago 30, Illinois

Rare Chemicals Research

(1) Ref: Porter, Durrell & Romm, Plant Physiol. 22, 149 (1947);Mattson, Jensen and Dutcher, Science 106, 294 (1947); Lakon,Ber. dtsch. chem. Ges. 60, 299, 434 (1942).

18

A.A.A.S. DIRECTORY OF MEMBERSThis Directory, now being printed, con

tains the names of 40,000 scientists: theiraddresses, positions, degrees, specialties, andprofessional positions.

Included in this 1600 page volume arethe names of scientists from 76 foreigncountries.A unique and valuable feature is its

Geographical Index from which may befound the names of specialists from everyfield of science in every city in the UnitedStates and Canada.

Introductory to the reports on the greatmeetings held by the A.A.A.S. and its affili -ated societies is a Historical Summary ofthe great scientific discoveries of 100 years.About 1600 pages, clothbound.To members, $8.50; to others, $9.50.

A.A.A.S., 1515 Massachusetts Ave.,Washington 5, D. C.

Please send me a copy of the A.A.A.S.Directory of Members and SummarizedProceedings, for which I enclose my check.

Name ......................................................................Address .................................................................

RUBBER RECIPE

Rubber compounds to the tune ofsome 35 million pounds a year gointo the Bell System plant. Eachcompound must meet many require-ments for resistance to humidity,oxygen, ozone, light and abrasion.The right properties depend onskillful selection and compoundingof ingredients; this is one of thejobs of Bell Laboratories.

Sulphur, one essential ingredientof rubber, can also be corrosive. ilThat seemed to rule out rubber ontelephone 'cords. But Bell chemistsfound that if they held sulphur tothe bare minimum, corrosion ceased.Now your handset cord has longlife, is less susceptible to moistureas, for example, from a wetumbrella.

Connecting your home to thetelephone wire on the street is a

"drop"-one hundred feet or moreof rubber-insulated wire. Once thiswire was protected from ozone, lightand abrasion by an impregnatedcotton braid; but water leached theimpregnant, and the braid rotted.Bell chemists tested scores of syn-thetics, and selected neoprene as anexterior covering with many timesthe life of braid.

Rubber is only one of many typesof insulation developed by the Lab-oratories for the Bell System; insu-lation is only one of the Laborato-ries' problems in providing a quick,economical path for your voice.

BELL TELEPHONE LABORATOARIESEXPLORING AND INVENTING, DEVISING AND PERFECTING FOR CON-

TINUED IMPROVEMENTS AND ECONOMIES IN TELEPHONE SERVICE. /

MICRO TECHNIQUES employing polarizedlight make possible significant savings oftime, effort, and material in detection andidentification of crystalline substances.For this reason Spencer Polarizing Micro-scopes, with their advanced optical andmechanical design, are becoming increas-ingly important to science and industry.A wide choice of models is available tomeet the needs of elementary and ad-vanced crystallographic work. We willgladly send you a catalog without ob-ligation. Write Dept. G3.

American w OpticalCOM PA NY

Scientific Instrument DivisionBuffalo 15, New York

1.