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NEW SERIEs SUBSCRIPTION, $6.00VOL. 86, No. 2223 FRIDAY, AUGUST 6, 1937 SINGLE COPIES, .15

A BRAND NEW TEXTBOOK

GENERAL PHYSIOLOGYBy L. V. HEILBRUNN

JUST READY! Dr. L. V. Heilbrunn is an experienced teacher and a recognized au-

thority on General Physiology. His brand new book is a completeENTIRELY NEW! and concise presentation of the entire subject and fills a long-existingneed for a text of this type. The practical worth of the text hasbeen proved in the classroom, because Dr. Heilbrunn has used it in mimeograph form fortwo years. Although the book is thoroughly up-to-date, the classical literature is notneglected, and the basic concepts are presented in such a way that the student can graspthe significance of modern physiological thought.

The book is understandable-lucid-and logical in its entire consideration of the subject.It is indeed an excellent presentation of the nature and mechanism of living matter as itis known today.The plan of the book is as follows: First the author discusses the nature of the subject,following this with a brief survey of the morphology of living cells and a thorough con-sideration of their physico-chemical make-up in the light of today's knowledge. Thenhe takes up the ""living machine," including discussions of nutrition, digestion, respira-tion, secretion and excretion. Energy relations are considered extensively in chaptersdealing with mechanical energy, heat, electricity, etc. Environmental effects, acclima-tization, irritability, conduction, reproduction, etc., are among the many other subjectsthat are thoroughly described and explained.The completeness, authority, and logical organization of this new textbook will undoubt-edly gain for it the enthusiastic acceptance not only of teachers and students, but ofpharmacologists, pathologists, human physiologists, and other workers in the field of gen-eral biology.By L. V. HEILDRUNN, Associate Professor of Zoology in the University of Pennsylvania. 603 pages, illustrated. Cloth,$5.00 net.

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2 SCIENCE-ADVERTISEMENTS

DELTA, ESTUARY, AND LOWERPORTION OF THE CHANNEL OF THECOLORADO RIVER, 1933-1935

By GODFREY SYKESA continuation of and supplement to the major

study of the stream dynamics of the lower Colo-rado River in the author's recent "The ColoradoDelta" (Publ. No. 460, published jointly with theAmerican Geographical Society of New York).The observations are of special significance be-

cause they include both the period before andafter the decisive changes brought about by thecompletion of Boulder Dam. The range of ob-servations has been extended to include the riverchannel between the mouth of the Gila River andthe foot of the Grand Canyon, over 700 samplesof bed silt having been secured in this section andsubjected to a standardized form of mechanicalanalysis.

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Some Fundamental Aspectsof The Cancer Problem

Symposium sponsored by the Sectionon Medical Sciences of the AmericanAssociation for the Advancement ofScience at Atlantic City, N. J., De-cember 29, 1986, to January 1, 1937

Published under the direction of the following committeeof prominent workers in medical science: William CharlesWhite, Chairman; Vincent du Vigneaud, C. C. Little, EsmondR. Long, and Carl Voegtlin. Edited by Henry B. Ward.The papers of this symposium bring out the advances

recently made in cancer research by leading investigatorsalong the three main approaches to the problem; namely,biology, chemistry, and physics. This monograph representsan authoritative survey of the subject. A brief summary ofthe papers will be found in SCIENCE for February 5, 1937,page 156.

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8 SCIENCE-ADVERTISEMENTS VOL. 86, NO. 2223

VOL. 86, No. 2223

two inches in diameter so that the hair will not becomeentangled in the cannula when the wing-nut is tight-ened. Having removed the hair, cut a slit about ahalf inch long between and parallel to the borders ofadjacent ribs. You may then thrust the cannulaquickly through the muscle tissue between the ribs,turn it through 900 quickly and then fasten the wing-nut. We have found it more satisfactory, however, toincise the intercostal muscles and parietal pleura be-cause occasionally the cannula point strips the parietalpleura from the chest wall and pushes it ahead of it.By this method, the cannula slips in easier and sinceit is so quickly done, no respiratory distress resultsin the animal, even if the lung collapses. You canquickly restore the intrathoracic pressure by suctionthrough a T-tube placed in the rubber tubing connect-ing the cannula with the recording tambour.

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THE USE OF DIALYSIS IN THE PREPARA-TION AND PURIFICATION OF IMMUNO-

LOGICALLY ACTIVE BACTERIALPRODUCTS*

THE problem of purifying active bacterial productsis frequently complicated by the presence of non-specific ingredients derived from the nutrient medium.We have recently employed a purely physical opera-tion, dialysis, to overcome this difficulty. The par-ticular bacterial products investigated were thosecapable of eliciting the phenomenon of local skinreactivity to bacterial filtrates;' the method described,however, appears generally applicable to other bac-terial products which are non-diffusible throughCellophane.

It was reported in a former communication2 thatthe active principles of the phenomenon of local skinreactivity to bacterial filtrates are retained by Cello-phane membranes. The observations of McClean3 onproduction of staphylococcus toxin in fluid media dif-fused through Cellophane suggested the possibility ofpreparing active filtrates free from non-specific ingre-dients, as described below.A diffused broth medium is prepared by immersing

Cellophane4 bags, containing saline, into nutrientbroth. Sterilization is accomplished by autoclaving.After standing at room temperature for 24 hours, theinner contents are inoculated and the apparatus incu-bated. During the abundant growth in the bags,

* This investigation has been aided by a grant fromEli Lilly and Co., Indianapolis.

1 G. Shwartzman, "Phenomenon of Local Tissue Reac-tivity and its Immunological, Pathological and ClinicalSignificance. " Paul B. Hoeber, Inc., Medical BookDepartment of Harper and Brothers, New York, 1937.

2 G. Shwartzman, S. Morell and H. Sobotka, Jour. Exp.Med., 65: 323, 1937.

3 D. McClean, Jour. Path. and Bact., 44: 47, 1937.4'" Cellophane" No. 600 was used.

observed thus far with many microorganisms, the out-side broth remains sterile. The production of potentculture filtrates under these conditions is consistent.The function of the outside broth is to supply dif-fusible nutrient substances to the growing bacteria.After various periods of incubation, the cultures areremoved and filtered. The filtrates obtained in thismanner are then redialyzed against saline, in Cello-phane bags.2 Diffusible substances which have notbeen rearranged to specific bacterial products are thusremoved. In many cases, practically water-clearpreparations are obtained. The final dialyzed solu-tions usually contain about 2 mgms total solids (ashfree) and 0.02 mgms total nitrogen. The method isvery practical, and large quantities of excellent start-ing materials for chemical investigations are readilyprepared. They are considerably lower in total solidsand nitrogen than most of preparations formerlyanalyzed.2

The filtrates give abundant precipitation with spe-cific immune sera, thus apparently containing a con-siderable amount of antigenic material. The activeprinciples of the phenomenon present in these prepa-rations are of considerable potency. In the case ofmeningococcus, the reacting titer approximates onehalf of that of "agar washings" filtrates. It may benoted that filtrates of meningoeoccus cultures in fluidmedia without the use of Cellophane have ordinarilya potency of 1/40 to 1/20 of the "agar washings."These principles are specifically neutralized by immunesera in "multiple proportions."

SAM MORELLGREGORY SHWARTZMAX

LABORATORIES OF THE MOUNTSINAI HOSPITAL

NEW YORK

BOOKS RECEIVEDBITTER, FRANCIS. Introduction to Ferromagnetism. Pp.xi+314. 147 figures. McGraw-Hill. $4.00.

HEILBRUNN, L. V. An Outline of General Physiology.Pp. 603. 122 figures. Saunders. $5.00.

HOUWINK, R. Elasticity, Plasticity and Structure ofMatter. Pp. xviii + 376. 214 figures. CambridgeUniversity Press, Macmillan. $6.00.

LANGSDORF, ALEXANDER S. Theory of Alternating Cur-rent Machinery. Pp. xviii + 788. 36 figures. McGraw-Hill. $6.00.

MYERS, CHARLES S. In the Realm of Mind. Pp. 251.Cambridge University Press, Macmillan. $2.50.

NORMAN, A. G. The Biochemistry of Cellulose, the Poly-uronides, Lignin, etc. Pp. 232. Illustrated. OxfordUniversity Press. $5.00.

SENNING, W. C. Laboratory Studies in ComparativeAnatomy. Pp. ix+188. 15 figures. $1.75. OutlineDrawings for Laboratory Studies in Comparative Anat-omy. $1.50. McGraw-Hill.

THORNDIKE, LYNN and PEARL KIBRE. A Catalogue ofIncipits of Mediaeval Scientific Writings in Latin. Pp.xvi + 926. Mediaeval Academy of America, Cambridge,Mass. To members of the Academy, $9.60. To others,$12.00.

130 SCIENCE

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Bitter-Introduction to FerromagnetismBy FRANCIS BITTER, Massachusetts Institute of Technology. International Series in Physics.314 pages, $4.00 -

Defines the problems of which the solution may be expected to reveal the fundamental processes which constituteferromagnetism and paves the way for a consideration of the subject from the point of view of solid solutions (impurematerials) rather than perfectly homogeneous pure substances.

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