ssachuseSC IENCBr~-1 D 't'NEW SERIESVOL. 83, No. 2148 FRIDAY, FEBRUARY 28, 1936

SUBSCRIPION, $6.00SINGLE COPIES, .15

PACKCHANIANELECTROPHORESIS APPARATUS

For the Isolation of Certain Protozoa from a Mixture of Bacteria and Proto-zoa, and for the Studying of Electrical Charges and Velocities of FilterableViruses.

Consists of a series of cells which can be easily isolated from each other thusfacilitating seven or more definite samplings from anodal and cathodal sectionswithout diffusion of liquid. Apparatus can be sterilized.

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2 SCIENCE-ADVERTISEMENTS

NEW WORK JUST READY

THEMICROSCOPIC ANATOMY

OF VERTEBRATESBy GEORGE G. SCOTT, Ph.D.

Professor of Biology in the City College, New York City

and JAMES I. KENDALL, Ph.D.Instructor in Biology in the City College, New York City

Octavo, 306 pages, illustrated with 167 engravings.Cloth, $3.75, net.

This is a college text-book in comparative vertebratehistology, sufficiently condensed to be covered in a singlesemester period. To this end it has been kept primarilyon a descriptive basis to accompany laboratory work. Anobjective is the mastery of technique and an importantchapter on this topic is included. Unlike most textsin anatomy and embryology, the emphasis is not placedon human material but on a variety of vertebrates sothat the book may truly serve as a survey of comparativemicroscopic anatomy and histology.

LEA & FEBIGERWASHINGTON SQUAREPHILADELPHIA, PA.

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The Phenomena ofLIFE

A Radio-Electric Interpretation

ByGeorge Crile

After years of research Dr. Crile at lasthas found a clue to the fundamentalnature of living processes. In. this bookhe presents his theory which suggests a

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The Philosophy of PhysicsBy Max PlanckThe dean of living physicists here sumsu his philosophy of physics. A workof commanding interest. $2.00

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Published by

UNIVERSITY of CALIFORNIA PRESSBERKELEY :: CALIrORNIA

2 SCIENCE-ADVERTISEMENTS VOL. 83, NO. 2148

SCIENCE-ADVERTISEMENTS

NEW

SPENCER LAMPFor Use with Binocular Microscopes

A NEW LAMP-designed to give sufficient illumination for binocularmicroscopes using objectives of high magnifying power. It is small,inexpensive and is equipped with a standard 100-watt, 120-volt bulb

that may be purchased at any electrical supply store.This Spencer No. 361 Lamp is so well ventilated that it may be handled

at any time. The visor is so arranged over the light opening that when thelamp is ten or twelve inches from the microscope the eyes at the eyepiecesare shaded.

Folder M-65 completely describes thisSpencer No. 361 and other MicroscopeLamps. Please address your request for

this folder to Dept. A-2.

FEBRuARY 28, 1936 3

SCIENCE-ADVERTISEMENTS

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Ag- electrode

-N HCI

-Pyrex glass

TYPE II

The correctness of the slope is shown in the followingexperiment.A solution containing 1 mole NH4C1 per liter, and

NH3 in the concentration indicated in the table showedthe following potentials at 300 C. = (in a constant tem-perature room).

[NH.] Electrode I, 7 megohms Electrode II, 4 megohms[NHs] (filled with .1 N HCI) (filled with .5 N HCI)Dfe-Total Dfe-TotalDifer- differ- Differ- differ-

ence ence ence ence

.001000 .2566 .3109.0602 .0598

.01000 .3168 .3707 }.0600 .1805 .0601 .1802

.1000 .3768 .4308.0603 .0603

1.000 .4371 .4911

The difference should be theoretically in each case.0601 volts; and the total difference over three unitsof pH is theoretically .1803 volts. This table is takenfrom measurements made by Dr. J. Bjerrum in thislaboratory, who has used this glass electrode forvarious investigations to be published later.

Except on very warm and humid summer days, notrouble of any kind was encountered in the use of thismethod.

LEONOR MICHAELIS

A SIMPLIFIED PROCEDURE FOR THE VOLU-METRIC MEASUREMENT OF SERIALLY

SECTIONED STRUCTURESBIOLOGISTS have frequently been able to determine

the volume of glands, etc., too small or diffuse to be

otherwise handled by outlining serial sections andmeasuring the outlines either by cutting out and weigh-ing or by use of a draftsman's planimeter. The useof this latter instrument is somewhat simpler, thoughin either case the method is laborious.In extensive use of this technique the author has

found it possible to so simplify the procedure that,aside from the preparation of the slides, very littleeffort is involved.The outlines, by projection or camera lucida, are

prepared in sequence on a continuous sheet of wrap-ping paper. The planimeter is set upon a large sheetof heavy clear celluloid (or other thin flat transparentmaterial) which is tacked down at the ends. A pin-hole near the center is made and marked as the startingpoint. The celluloid sheet should be large enough sothat in all measurements the planimeter rides entirelyupon it.

The sheet with outlines are slipped under the cellu-loid and a point on the first perimeter is broughtunder the starting point. The pointer is tracedaround, measuring the first outline. Then without dis-turbing the planimeter the outline sheet is slippedalong until a point on the next outline is under thestarting point. When this is measured the planimeterautomatically adds its area to that of the preceding.If it is desired to subtract any particular part of theoutline the planimeter is run backwards. The finalsum of the areas is given by one reading of the plani-meter. From this and the thickness of the sectionsthe volume is calculated.By this method a gland involving over one hundred

sections can be carefully outlined, measured andchecked in less than two hours. A comparison withthe paper weight method showed somewhat less varia-bility and the further advantage of giving actualvolumes.

WILLIAm ETKINCOLLEGE OF THE (eITY OF NEw YORE

ANDTHE AMERICAN MUSEUM oF NATURAL

HISTORY

BOOKS RECEIVEDCRILE, GEORGE. The Phenomena of Life: A Radio-Elec-

tri-c Interpretation. Pp. 379. 113 figures. Norton.$3.50.

EDGEWORTH, F. H. The Cranial Muscles of Vertebrates.Pp. viii + 493. 841 figures. Cambridge UniversityPress, Macmillan. $30.00.

PETERS, J., A. LODGE, E. J. TERNOUTH and E. GITFORD.Mathematical Tables. Vol. V: Factor Table: Givingthe Complete Decomposition of All Nu-mbers Less than100,000. Pp. xv + 292. British Association for theAdvancement of Science. Cambridge University Press,London. 20/-.

STOKLEY, JAMES. Stars and Telescopes. Pp. xiii+319.40 figures. 49 plates. Harper's. $3.00.

214 SCIENCE

FERAY2,13 CEN EA V RIE E T

The American Journal of AnatomyPublished by The Wistar Institute

Charles R. Stockard, Managing Editor, Cornell Univ. Med. School

VoL 58 Contents for March, 1936 No. 2H. B. VAN DYKE AND G. CH'EN. Observations on the biochemistry of the genital tract of the female macaque particularly

during the menstrual cycle. Three text figures and three plates.G. B. WISLOCKI AND L. S. KING. The permeability of the hypophysis and hypothalamus to vital dyes, with a study of

the hypophyseal vascular supply. Twenty-eight text figures.E. M. GLIDDEN AND C. F. DE GARIS. Arteries of the chimpanzee (Pan spec.?): I. The aortic arch; II. Arteries of the

upper extremity; III. The descending aorta; IV. Arteries of the lower extremity. Seven text figures.E. J. CAREY. Studies in the wave-mechanics of muscle. I. Vibratory motor nerve ending and related radiation-patterns

of muscular cross-striations. Twenty-two plates.M. M. WINTROBE AND H. B. SHUMACKER, JR. Erythrocyte studies in the mammalian fetus and newborn. Erythrocyte

counts, hemoglobin and volume of packed red corpuscles, mean corpuscular volume, diameter and hemoglobincontent, and proportion of immature red cells in the blood of fetuses and newborn of the pig, rabbit, rat, cat, dogand man. Eight text figures.

G. H. DARON. The arterial pattern of the tunica mucosa of the uterus in Macacus rhesus. Eleven plates.H. B. LATIMER. Weights and linear measurements of the adult cat.

Price $7.50 per volume, Domestic; $8.00 per volume, ForeignIssued bimonthly

Many early volumes are still available. Prices upon request

Address subscriptions to

The Wistar Institute of Anatomy and Biology36th Street and Woodland Avenue

Philadelphia, Pa., U. S. A.

STAIN TECHNOLOGYA JOURNAL FOR MICROTECHNIC

Beginning with the January number of this journal, the sectionentitled LABORATORY HINTS FROM THE LITERATURE has been increasedin size.

Each number of the journal now contains between 75 and 100abstracts of papers giving technic in all fields of microscopy, as wellas papers dealing with the biological uses of dyes. Each abstract notonly indicates the procedures included in the original article but gi"vesthe author's technic in sufficient detail to follow without having toconsult the original paper. STAIN TECHNOLOGY thus truly becomes,as implied by its sub-title, A JOURNAL FOR MICROTECHNIC.

Issued quarterly Subscription $2.25 a year

Published by the

BOOK SERVICE OF THE BIOLOGICAL STAIN COMMISSIONLock Box 299 Geneva, N. Y.

Send for Sample Copy

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PIZBRuARY 28) 1936 SCIENCE-ADVERTISEMENTS 5