APRIL 2, 1943 SCIENCE-ADVERTISEMENTS 9

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CHEMISTRYGeneral

DEMING-General Chemistry.Fourth Edition. 769 pages. 6 by 9. $3.50

DEMING-HENDRICKS-Introductory CollegeChemistry.

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756 pages. 6 by 9. $3.50DEMING - Laboratory Manual of College

Chemistry.268 pages. 8i by 11. $1.75

DEMING-ARENSON - Exercises in GeneralChemistry and Qualitative Analysis.

Fourth Edition. 326 pages. 5j by 8J. $1.80GORDON - TROUT - Introductory College

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HATCHER - An Introduction to ChemicalScience.

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QualitativeENGELDER-Textbook of Elementary Quali-

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ENGELDER- DUNKELBERGER -SCH I LLER-Semi-Micro Qualitative Analysis.

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HARTSUCH-Elementary Qualitative Analysis.262 pages. 7$ by 10. $2.50

QuantitativePIERCE-HAEN ISCH-Quantitative Analysis.

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Third Edition. 364 pages. 6 by 9. $3.00

ENGELDER-Elementary Quantitative Analy-sis.

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MAASS-STEACIE- An Introduction to thePrinciples of Physical Chemistry.

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GARARD-An Introduction to Organic Chem-istry.

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FUSON - CONNOR-PRICE-SNYDER-A BriefCourse In Organic Chemistry.

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PHYSICSBLACKWOOD-Introductory College Physics.

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APPL 2, 1943 SCIENCE-ADVERTISEMENTS 9

SCIENCE-SUPPLEMENT VoL. 97, No. 2518

SCIENCE NEWSScience Service, Washington, D. C.

NEW SEISMOGRAPH FOR THE NATIONALASTROPHYSICAL OBSERVATORY

OF MEXICOEARTHQUAKES and sleeping volcanoes in Mexico will be

studied intensively by one of the world's most sensitiveseismographs, to be installed in Mexico's National Astro-physical Observatory through the cooperation of Ameri-can scientific men with -the State Government of Puebla,headed by Dr. Gonzales Bautista.The Mexican Ambassador, Don Francisco Castillo

Najera, in Washington, announced the acquisition of theinstrument, and Dr. Harlow Shapley and Dr. L. Don Leet,of Harvard University, state that arrangements for theshipping and installation of a Benioff vertical-componentseismograph, which has recently been thoroughly testedby Daniel Linehan, of Weston College, have been con-

cluded by the Committee on Geophysical Research ofHarvard University. The instrument was provided bythe National Research Council in Washington and was

originally intended for use in the studies of local earth-quakes. Recent events in Mexico have shown that seis-mographs of this type, located where they will contributenew information about Mexican earthquakes, will con-

tribute also to knowledge of volcanic activity.The seismograph will soon be installed at Tonantzintla,

just east of the famous towering twin mountains, Popo-catepetl and Ixtaeeihuatl.

This new seismograph is one of the latest models of a

type that has proved itself to be among the world's best.It was developed by scientists at the California Instituteof Technology. Some of the earliest investigations withBenioff seismographs were made at the Oak Ridge, Mass.,station of Harvard University, resulting in the discoveryof previously unsuspected minor seismic activity in thisarea. The great success of Harvard with this instrumenthas led to its widespread adoption in this country andabroad.The seismograph produces a record of ground vibrations

in the form of lines on photographic paper. It is capableof magnifying ground motions by as much as 250,000times. At Oak Ridge it records the passing of trainseight miles away as well as earthquakes on the oppositeside of the globe.

Mexico is one of the best natural laboratories availablefor a study of the related problems of earthquakes andvolcanoes. There are both active and recently extinctvolcanoes and numerous earthquakes. Some of theseearthquakes, in fact all that are in the volcanic regions,are unusual in that they occur at distances of around sixtymiles below the surface. Just enough information hasbeen accumulated in recent years to cause investigatorsto be considerably puzzled and extremely curious about

the connection between these earthquakes and the vol-

canoes. This curiosity was sharpened recently by the

reported appearance in Mexico of a new volcano in a

region where such earthquakes have been occurring over

a period of years.

These investigations into the relationship of volcanoesand earthquakes mark an interesting cycle in seismologi-cal thought. The earliest theories of the origin of earth-quakes held that all earthquakes were caused by volcanoes.Subsequent opinions, based on new facts, held that allearthquakes were caused by crust-distorting forces, andthat any relationship to volcanoes is purely coincidental.It now appears that the forces which produce earthquakesin certain areas may also cause volcanic eruptions.The installation of a high-sensitivity instrument in

Puebla will provide an ideal opportunity, one of the fewin the world, to study the day-by-day minor manifesta-tions of the forces causing earthquakes and volcanic erup-

tion, contributing perhaps ultimately to the solution ofthe larger problem of the origin of mountains.

THE SPEED OF CHEMICAL REACTIONSHow the methods by which a chemist determines the

speed of a chemical reaction can be effectively used inthe fields of physics and biology was described by Dr.Henry Eyring, professor of chemistry at Prineeton Uni-versity, at the University of Louisiana in a lecture whichis also to be delivered before local chapters of the honor

society of Sigma Xi throughout the country.Dr. Eyring has developed improved formulas for pre-

dieting reaction rates by use of thermodynamics, statis-tical mechanics and the quantum theory. These formulascan be applied, he pointed out, to such apparently unre-

lated subjects as the flow of fluids, the velocity of soundand of nerve impulses, the light of luminous bacteria, theaction of drugs and of enzymes. They bring a new andilluminating method of investigation into these fields.The flow of fluids can be pictured as arising from indi-

vidual molecules jumping from one equilibrium positionto an adjacent empty one, just as in a chemical reactionthe molecules jump from one position of equilibrium toanother one, forming a new compound. The formulas forreaction rate successfully predict the velocity of flow ofa liquid. When a liquid is compressed, some of the holesare squeezed out of it. The flow becomes more difficult.The liquid becomes thick-viscous. The picture thusexplains this well-known fact.When a sound wave travels in air, it must be passed

on from molecule to molecule. Its speed is the averagespeed of the heat motion of the molecules. In water, theheat motion of the molecules is the same, but they are

closer together. They bump each other more often, so

that the sound impulse is passed along about eight timesas rapidly as in air.A nerve impulse travels about one fifteenth as fast as

sound travels in water. This is interpreted by Dr. Eyringas meaning that each molecule must make about fifteen

tries to get the message over to the next molecule. Thelight emitted by luminescent bacteria is due to the cata-

lytic action of an enzyme. The catalyzing molecule, after

bringing about the oxidation of the luciferin molecule,finds itself in an excited state and emits a quantum of

10

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BASIC AGRICULTURAL TEXTSMILK AND MILK PRODUCTS. New third edition

By C. H. ECKLEs, Late Chief, Division of Dairy Husbandry, WiuTS B. COMBS, Professor ofDairy Husbandry, and HAROLD MACY, Professor of Dairy Bacteriology, University of Min-nesota. McGraw-HiU Publications in the Agricultural Sciences. 397 pages, 6 x 9, illus-trated. $3.50

This well known, widely used text, which deals with both scientific data and practical meth-ods in the preparation of milk and milk products for the market, has now been thoroughlyrevised to cover advances in the subject made during the past seven years. At the same time,the authors have preserved the original plan and purpose of the preceding editions to give acomprehensive treatment of present-day knowledge of the chemistry and bacteriology of milk,of common dairy processes, of the manufacture of dairy products, of dairy testing, and ofdairy calculations.

FIELD CROPSBy HOWARD C. RATHER, Professor and Head, Farm Crops Department, Michigan StateCollege. McGraw-Hill Publications in the Agricultural Sciences. 545 pages, 6 x 9, illus-trated. $3.75

In a stimulating narrative style the author of this book discusses the leading field crops ofthis country, their place in its economic structure, their adaptation and distribution, theirbotanical classification, and the best cultural methods proved by experimentation. The bookstresses practices and principles of enduring merit, and discusses varieties and the signifi-cance of varietal improvement, rather than specific crop varieties of temporary or local sig-nificance.

LIVESTOCK PRODUCTIONBY WALTER H. PETERS, Chief, Division of Animal and Poultry Husbandry, University ofMinnesota. McGraw-Hill Publications in the Agricultural Sciences. 450 pages, 6 x 9, illus-trated. $3.50

This textbook for the first course in animal husbandry gives a survey of the knowledge essen-tial to an understanding of the problems and opportunities in livestock production. It citesthe important products of the several kinds of farm animals and notes their applications toproduction. It contains brief statements of the origin, distribution, and characteristics ofeach of the important breeds and the methods used to improve them. It deals with the feed-ing, management and care, judging, and marketing of beef cattle, dairy cattle, swine, sheepand goats, and horses and mules.

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ApmI 2, 1943 SCIENCE-ADVERTISEMENTS 11

Aldwych House, London, W.C.2

SCIENCE-SUPPLEMENT

blue light. Temperature and pressure affect the intensityof the light in the same way they affect chemical reactionrates. Sulfanilamide reduces the light intensity and sodoes urethane. But the two together reduce the light lessthan does sulfanilamide alone, indicating that these twodrugs are antagonistic and form a combination.From these studies of luminescence, Dr. Eyring expects

a more detailed understanding of the action of drugs andof biological enzymes in general.

VITAMINSVITAMIN or other dietary means of preventing and cur-

ing now uncontrollable diseases, as we now control scurvy,pellagra and rickets, was predicted for the future in aSigma Xi lecture at Purdue University by Professor C.A. Elvehjem, of the University of Wisconsin.

Recent studies in his own and other research labora-tories of the twelve or more B vitamins furnish the basisfor Professor Elvehjem 's forecast for the future of nutri-tional research.Lack of one of the newest B vitamins, folic acid, may

be the cause of a blood disorder, a sort of white bloodcell anemia, that develops occasionally in patients gettingsulfa drug treatment and also sometimes without suchtreatment. The same condition develops in rats followingtreatment with certain sulfa drugs, and it also developsin monkeys deprived of the vitamin. The reason the ratsget the condition seems to be that the sulfa drugs stopthe growth of microorganisms in the rat intestinal tractwhich normally manufacture some of the B vitamins.

In both monkeys and rats the white blood cell anemia,though induced by diet in the one case and by sulfa drugsin the other, can be prevented by folic acid. The condi-tion may develop following twenty days of sulfa drugtreatment because the patients had been on short rationsof folic acid and could not stand further depletion by thedrug of their reserve supply of this vitamin. "We canonly speculate as to the importance of the other factorsin human nutrition," Professor Elvehjem concluded,"but I am willing to wager that equally important rela-tionships will develop. As research continues we maylearn from it nutritional means of handling diseases whichare uncontrollable today as readily as we now controlscurvy, rickets and pellagra.1"

Biotin, inositol and p-aminobenzoic acid are other newB vitamins which the latest studies show may have sig-nificance in human nutrition, besides those with whichbiochemists, nutritionists and even lay persons are now

familiar: thiamin, riboflavin, niacin, pantothenic acid,pyridoxine and choline. Two chemically unknown fac-tors needed by the chick for growth and feather produc-tion and one or more factors of significance in guinea pignutrition complete the tally of now known B vitamins.

ITEMS

QUININE content of newly discovered cinchona standscan now be analyzed on the spot by a new portable deviceinstead of sending bark samples to remote laboratories.The first four units have been shipped to South Americato speed development of quinine sources and for inauguraltests under field conditions. Knowing that quinine

fluoresces or glows under ultraviolet light, Martin S.Ulan, of Rutgers University, consultant to the BEWOffice of Imports, went to work with his associates todevelop a machine that would make laboratory testingof cinchona bark unnecessary. Starting with an instru-ment used to test fluorescent minerals, the galvanometerwas dispensed with and a set of tubes each containing adifferent strength of quinine solution substituted; eachwith a different degree of fluorescence. By comparingthese with an unknown sample the quinine content canbe calculated. This test, conducted in a few minutes inthe heart of the jungle, is expected to be nearly as accu-rate as more complicated laboratory procedures. Simpleinstructions included with the new device can be followedby a layman without technical training.

"STRIKING clinical improvement" in nine out of tenpatients suffering with ! 'shipyard eye" has been achievedby injections into the veins of blood serum from otherpatients already recovering from the eye condition, isreported by Dr. Alson E. Braley and Dr. Murray Sanders,of New York, in the Journal of the American MedicalAssociation. The group of cases treated is small andfurther studies with control cases are needed before con-valescent serum can be accepted as a cure for the condi-tion. However, since this ailment is occurring in epi-demics in industrial areas in many parts of the country,and since no other treatment has materially shortened thecourse of the disease, it is felt that attention should becalled to the possibilities of convalescent serum treatment.Seven of the ten patients were "clinically cured," sixof them in forty-eight hours. In two others the normalcourse of the disease was shortened and corneal changespossibly aborted. One case is classed as a failure becauseadequate information following treatment could not beobtained.

PLASTIC lithographic printing plates, made from poly-vinyl alcohol resin, are reported to be in use in the Armyfor printing colored maps and other military documents,and in mobile field printing units. Their use saves fromthree to eight times their weight in critical aluminum andzinc. The development came about through the use ofpolyvinyl alcohol as a coating on zinc to improve theprinting quality of the metal. It became apparent thatthe actual printing was from the plastic and not themetal, and that other material could as well be used forthe base as zinc and aluminum. In the new plate thebase is paper impregnated with the polyvinyl alcohol resinwhich gives it the required strength and stability. It iswaterproofed with a coating of another resin. Twosheets are then laminated to form the base, and the print-ing surface coated with the polyvinyl alcohol resin. Crea-tion of the printing image is the same as with metal.The resin plastic is sensitized with bichromate of ammo-

nia. It is exposed to light, treated with the developingink, developed in water and etched, and is then ready foruse in the press. The development of this plastic forlithograph printing plates was carried out in the labora-tories of the du Pont Company, and the plates are madeby a Boston company. The Army at present has pre-empted the entire output, but it is expected will be avail-able at a later date to the printing trade.

VOL. 97, NO. 251812

APRIL 2, 1943 SCIENCE-ADVERTISEMENTS 13

Practical Guidance} or the Studentin These New Texts

CHEMOTHERAPY OF GONOCOCCIC INFECTIONSby RUSSELL D. HERROLD, Associate Professor of Surgery (Urology), Collegeof Medicine, University of Illinois. 140 pages. PRICE, $3.00

The tremendous incidence of gonococcal infections and the revolution in their treat-ment through chemotherapy warrant the interest of every student.

In this new monograph, Dr. Herrold brings up to date all data that have proved ofvalue in the management of these infections through chemotherapy in his own clin-ical experience.

Experience with sulfathiazole alone includes observation of 800 patients in the pasttwo years. Approximately one thousand additional patients were observed in whichneoprontosil, sulfanilamide, sulfacetamide, sulfapyridine, sulfadiazine, and threeother sulfonamide derivatives since withdrawn from clinical investigation wereemployed.

METHODS FOR LABORATORY DIRECTIONSDIAGNOSTIC BACTERIOLOGY IN BIOCHEMISTRYby ISABELLE G. SCHAUB & M.KATHLEEN FOLEY. About 850pages. PRICE, about $3.00The outstanding addition to this newSecond Edition is a chapter which willprove of practical, time-saving value toevery user. It presents methods ofrapid identification of commonly oc-curring pathogenic bacteria by colonycharacteristics. Throughout, the datahave been brought up-to-date, and newlaboratory tested methods included.The authors emphasize the selection ofone single, simple method and mediawhich can be relied upon.

r u- - -_ _IThm V_ V- MCIRRY (7

by VICTOR C. MYERS. 288 pages,17 illustrations. PRICE, $3.50

Covering biochemistry, clinical bio-chemistry and dental biochemistry, thismanual is usable by both dental andmedical students. Separate and dis-tinct sets of laboratory directions areprovided for dental students. Lec-tures, assigned readings, demonstra-tions and individual laboratory workare covered. Throughout, an effort ismade to coordinate lectures and lab-oratory work.

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SCIENCE-ADVERTISEMENTS 13APRIL 2, 1943

14 SCIENCE-ADVERTISEMENTS VoL. 97, No.

cAnnouncing: VOLUME V

ANNUAL REVIEW OF PHYSIOLOGYPublication date, April, 1943 Editor: J. MURRAY LUCK

Published byAMERICAN PHYSIOLOGICAL SOCIETY

andANNUAL REVIEWS, INC.

Associate Editor: VICTOR E. HALLEditorial Committee:

A. J. CARLSONJ. F. FULTONM. H. JACOBSF. C. MANNW. J. MEEK

"As a contribution to the history of science these annual volumes afford an invaluable record of thecurrently most active fields and critical analyses by experts in them." (Isis, 93, 1942.)

"Increasingly scientists are coming to rely upon the Annual Review for rapid and reliable orientationtoward recent developments in the broad field of physiology." (The Journal of Clinical Endocrinology,Vol. II, No. 1, 1942.)

CONTENTS. Physiological and Pathological Effects of Ultraviolet Radiation, H. F. Blum; PhysicalProperties of Protoplasm, C. V. Taylor; Phsiological Aspects of Genetics, Jack Schultz; DevelopmentalPhysiology, W. F. Windle; Physiology of Bone, F. C. McLean; Energy Metabolism, E. B. Forbes and L.Voris; Respiratory System, C. L. Gemmill; Muscle, Ernst Fischer; Digestive System, R. C. Herrin; Blood,H. D. Bruner; Lymphatic System, P. D. McMaster; Heart, F. D. Johnston and F. N. Wilson; Nerve andSynaptic Transmission, B. Renshaw; Visceral Functions of the Nervous System, H. W. Magoun; Tempera-ture Regulation, L. P. Herrington and A. P. Gagge; Liver and Bile, J. L. Bollman; Sense Organs, H.Davis and S. H. Bartley; Metabolic Functions of the Endocrine System, B. A. Houssay and V. Deulofeu;Physiology of Mammalian Semen, J. MacLeod; Endocrinology of Reproduction, C. A. Pfeiffer; Physio-logical Psychology, N. Cameron and H. F. Harlow; Biological Assay, C. I. Bliss and McKeen Cattell.

Approximately 600 pages Author and Subject Indexes$5.00 per copy (American funds) Postpaid In U.S.A.

On Sale by

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domestic material. In the manufacture ofBacto-Agar extraneous matter, pigmented portions,and salts are reduced to a minimum, so that thefinished product in the form of fine granules willdissolve rapidly, giving clear solutions.

Bacto-Agar is distributed only for use in

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Bacto-AsparagineBacto-Asparagine is a purified amino acid

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14 SCIENCE-ADVERTISEMENTS Vol.. 97, No. 2518

SCIENCE-ADVERTISEMENTS 13

TH E "LUMETRON"

PHOTOELECTRIC FLUORESCENCE METERThe Model 402EF Fluorescence Meter is the most complete model in the line -of LumetronPhotoelectric Colorimeters. Its applications include measurement of fluorescence, transmis-sion, turbidity, ultraviolet absorption and reflection. It is particularly suited to the de-termination of Vitamin B1 (thiochrome and diazonium salt reaction), Vitamin A by ultra-violet absorption; also Vitamin D, nicotinic acid, iron, and carotene by transmission in thevisible range.

FeaturesStability and reproducibility of readings, by the use of a bridge circuit with balance cell to

eliminate the Influence of light Intensity variations of the mercury vapor lamp.

Exceptionally high sensitivity, permitting accurate measurement of extremely low concen-trations of Vitamin B1 and B.

High specificity, obtained by narrow-band filters for the exciting light.No appreciable deterioration of Vitamin B1 and B2 during tests.

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16 SCIENCE-ADVERTISEMENTS VOL. 97, No. 2518

SCIENCE-ADVERTISEMENTS 17

COORS "U.S.A."

PORCELAIN FILTER CYLINDERS

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American made filters,offered for the samepurposes as, and gen-erally equivalent to,corresponding Chamiberland.-Pasteur Filters

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FILTER CYLINDERS, Coors U. S. A. Porcelain. Offered for the same purposesas the Chamberland-Pasteur Filters previously imported from France. Identical inshapes and dimensions with the French filters and with porosities generally equivalentto those of the corresponding Chamberland-Pasteur Filters.

While we have not as yet had sufficient experience with these filters to make definiteclaims regarding them, reports from laboratory workers-and repeat orders-indicatethat they will be found satisfactory for the purposes intended.

Porosities increase in fineness from P (porosity) 2 to 7, equivalent generally toChamberland-Pasteur porosities L2 to L7, respectively, in which series L2 was consid-ered a rapid prefilter, L, was less porous but used for rapid filtering, L5 medium porosity,7 a laboratory filter of dense constitution for fine filtering and for filtration of bacteria,sera, etc., and for pressure filtration. These filters can be regenerated by incineration inan electric muffle furnace at dull red heat.5107-N. Filter Cylinders, Coors Porcelain, Porosity 7, as above described, with glazed flange and nipple.

Size of cylinder approximately 205 x 25 mm, diameter of flange 40 mm, diameter of nipple,13 mm. Suitable for positive pressures up to 15 to 17 lbs. Generally similar to Chamber-land-Pasteur Filter "Bougie B " ................................ 2.50

5107-Q. Ditto, but coarser, i.e. Porosity 5; suitable for general filtrations and comparable with Chamber-land-Pasteur Filter " Bougie F " ......................... 2.50

5107-R. Ditto, but still coarser, i.e. Porosity 3, for more rapid filtering . 2.505108-A. Filter Cylinders, Coors Porcelain, Porosity 2, as above described, without flange or nipple but

glazed for some distance below the top. Can be used for a variety of work as, for example,in the Martin Filter Apparatus.Length, mm ............................. 55 75 155Diameter, mm ............................ 10 15 15

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18 SCIENCE-ADVERTISEMENTS VoL. 97, 2518

Anti-Aircraft Gun Crew -Official U. S. Navy Photograph

"Fire when ready!"Dramatic seconds pass while the

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the manufacture of some of the most in-tricate optical devices to Spencer becauseof a long record of success in producingscientific optical instruments of greatprecision.

In addition to thousands of standardmicroscopes and other instruments being

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VOL. .97, No. 251818 SCIENCE-ADVERTISEMENTS