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Off Press June 15th

NEW VOLUME 4

METHODS IN MEDICAL RESEARCHEDITED BY MAURICE B. VISSCHER, M.D.

Professor of Physiology, University of Minnesota

4 LARGE SECTIONS ON: Other Available1. Histochemical Staining Techniques Volumes in this Series

Edited by George Gomori, M.D.Volume 1.-Van R. Potter,2. Fluid and Electrolyte Distribution Ph.D., Editor-in-Chief

Edited by L. B. Flexner, M.D. Assay of Antibiotics

3. Studies on Gastrointestinal Pressures, Innervations Circulation: Blood Flow Measure-

mentand Secretions Selected Methods in Gastro-

Edited by J. P. Quigley, M.D. enterologic ResearchCellular Respiration

4. Tissue Culture Methods 370 pages; 83 illustrations. $8.00Edited by C. M. Pomerat, Ph.D.

Individually and collectively, the volumes of Methods in Medical Re- Volume 2.-J. H. Comroe, Jr.,search thus far published have been gratefully received by all con- M.D., Editor-in-Chiefcerned with medical investigative techniques and their application. Study of Bacterial VirusesThis is because the series assembles in compact, organized fashion a Pulmonary Function Testswealth of data and techniques which never have been published else- Assay of Hormone Secretionswhere or which can be secured only by laborious search through a vast 361 pages; 51 illustrations. $6.50literature and then frequently found to be incomplete.Each of the volumes and its component sections are edited by au- Volume 3.-Ralph W. Gerard,thorities in the fields under consideration. Other investigators are then M.D., Editor-in-Chiefinvited to review and comment. The result is a masterly collection of Genetics of Micro-organismsdiscussions and appraisals covering principles, technics, results, future Assay of Neurohumorstrends-even equipment and its sources of supply. Selected Psychomotor Measure-With publication of each succeeding volume, the indispensable char- ment Methodsacter of the series becomes more impressively apparent. Study of Peptide StructureVolume 4-306 pages, 52 illustrations, $7.00, postpaid 312 pages; illustrated. $7.00

Liberal Monthly __. --- -rn-rn -Payment Plan Availablee I The Year Book Publishers, Inc.,Purchase of this series /200 East Illinois Street, Chicago 11, Illinoismay be arranged onconvenient monthly Please send books checked, postpaid.terms. No carrying o Remittance Enclosed Dl Payment Plan Desiredcharge is made; mini- _mum payment, $5.00. Methos in Medical ResearchIf this plan is desired, El Volume 1. $8.00 El Volume 3. $7.00please enclose two El Volume 2. $6.50 0 Volume 4. $7.00credit references withyour order. Name.Street .

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June 22, 1951 1

- Hil~~Hll BooksMINERALOGY. New 4th edition

By EDWARD H. KRAus; WALTER F. HUNT; and LEWIS S. RAMSDEL, University of Michigan.Ready in summer 1951

An exceptionally thorough revision of this leading text. The Determinative Tables have been com-pletely redone, including many additional minerals and reflecting the advances in identifyingmethods. A large number of the illustrations are new. As in previous editions, the book providesin a clear, concise style all the student of general mineralogy needs to know about 250 of the mostimportant minerals.

METEOROLOGY. With Marine Applications. New 2nd editionBy WILLIAM L. DONN, Brooklyn College. 465 pages, $5.50

A general and descriptive text, this book first considers the observational and theoretical aspects ofthe basic weather elements. Subsequent discussions treat primary and secondary wind systems, in-ternational weather codes, and modern weather theory of air masses, and the study of oceans, tides,etc. Explanations are clear and informal, yet exceptionally complete.

EVOLUTION. New 2nd editionBy A. FRANKLIN SHULL, University of Michigan. McGraw-Hill Publications in the ZoologicalSciences. 322 pages, $5.00

Treats evolution from the genetic standpoint. This treatment includes the origin of change by muta-tion and chromosome reorganization, demonstration that such changes occur in nature, recombina-tion of such changes in sexual reproduction, polyploidy, geographic races, reproductive isolation, theformation of societies (including man's), and the origin of life.

EXPERIMENTS IN BIOCHEMISTRYBy M. S. DUNN, University of California, and WILLIAM DRELL, California Institute of Tech-nology. In press

A guide to advanced laboratory work, including much more theory and reference data than iscustomary in lab manuals. Covers isolation, synthesis, analysis and determination of biologicalsubstances including amino acids, peptides, etc. Emphasis is in completeness of lab directions,yields and purity of products, precision and accuracy of quantitative data, integration of qualitativetests for the identification of substances, explanation of chemical reactions, and quality of results.

Send for copies on approval

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SCIENCE, Vol. 113

McGR-AW-HIILL

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Dulcitol C. P. (Dulcite)d (-) Erythrose1 (+) Erythrose

EsculinFructose 1, 6-Diphosphate (barium salt)Fructose 1, 6-Diphosphate (calcium salt)

Fructose 1, 6-Diphosphate (magnesium salt)Fructose-6-Phosphate (barium salt)

1 (-) Fucose (Rhodeose)Galactosamined (+) Galactose

d-alpha-Gala-heptose (d-Gala- 1-Mannoheptose)d-alpha-Glucoheptose (d-Gluco-d-guloheptose)d-Glucoheptulose (d-Gluco-d-sorbo-heptose)

d-Gluconic-gamma-lactoned (+) Glucosamine HCI (Chistosamine)

Glucose 1 Phosphate (dipotassium salt)Glucose 6 Phosphate (barium salt)

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SCIENCE, Vol. 113

PHOTOVOLTLine-Operated ElectronicMULTIPLIER-PHOTOMETER

Mod. 520-M

For the exact measurementof extremely low light value.down to 1/10,000 microlumen.

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4

The Bell System's new automatic method of adjusting telephone ringers uses a beamof light passing between the gongs to a photoelectric cell. When test currents areapplied to the ringer the machine decides whether to change the spring tension orthe magnetic pull. After each change it tests again until the ringer is in perfect adjust-ment-and the whole procedure takes only 30 seconds.

ToYu, it's your familiar telephone bell.To telephone engineers, it's a "ringer." Andit has two jobs to do.

It must ring, of course, when sonreone callsyou. And it must overlook the numerous elec-trical impulses which do not concern it, suchas those sent out by your dial.

Ability to respond to some impulses, toignore others, requires exact adjustment be-tween the pull of a magnet and the tension ofa spring. If they are out of balance your tele-phone might tinkle when it oughtn't, or keepsilent when it should ring.

In the past, adjustment was made by hand,little by little until the proper setting wasreached. It took time. But now Bell Labora-tories engineers have developed a machinewhich adjusts new ringers perfectly, beforethey leave the Western Electric Companyplants where they are made. And the opera-tion takes just 30 seconds.

This is another example of how the Lab-oratories work constantly to improve everyphase of telephony - keeping the costs lowwhile the quality of service grows higher andhigher.

BELL TELEPHONE LABORATORIES 4WORKING CONTINUALLY TO KEEP YOUR TELEPHONE SERVICE ONE OF TODAY'S GREATEST VALUES

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SCIENCE, Vol. 113

I M.M

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6

What GENERAL ELECTRIC People Are SayingA. H. ADAMSF. L. TEUSCHERApparatus DepartmentCONNECTION D1AGRAMS: A new type of con-nection diagram has been developed [forindustrial control panels] which overcomes theundesirable features of the older type by pro-viding an accurate and completely detailedscale representation of the panel. A photo-graphic reproduction process is employed toproduce the scale diagram in less time. Mechan-ical as well as electrical details are shown.The major advantage of the new diagram is

that the panel and its components are to scale;the arrangement and size of symbols agreeexactly with the layout of devices on the panelas manufactured. Relative heights, length ofwire runs, and location of studs and terminalscan be scaled directly from the diagram.Positive identification and location of devicesmake the scale diagram particularly usefulduring manufacturing, installation, and main-tenance.

General Electric ReviewFebruary, 1951

A. W. WHITEE. 0. HENRICKSONF. W. FERNALDApparatus Department

TURBOSUPERCHARGERS: At 25,000 feet altitudea commercial transport engine which can de-velop only 1300 horsepower will produce, witha turbosupercharger, 2700 horsepower....The advantages of high-altitude flying,

proven by turbosupercharged military bombersand transports, led the Boeing Airplane Com-pany to use turbos on the world's largest luxuryliner, the double-deck Stratocruiser. This four-engine plane can carry 75 passengers and isdesigned for intercontinental service.With an operating altitude as high as 25,000

feet, four General Electric model BH-4 turbo-superchargers accelerate the large plane to amaximum cruising speed of over 300 miles perhour. The maximum range is over 4000 miles...

Started in transport service early in 1949,the Stratocruiser has several times lowered thetime of the trans-Atlantic record for com-mercial airliners. The extra power provided foreach engine by the turbosupercharger is furtherillustrated by the fact that the large ship is

capable of climbing to 15,000 feet with onlytwo engines operating....

Strange as it may seem, the conditions underwhich the BH-4 turbos operate in the Strato-cruiser have proved to be actually more severethan are normally experienced with militaryairplanes. The temperature of the engineexhaust is higher in the commercial planes be-cause military aircraft normally operate athigher engine powers and richer fuel mixtures.The lower exhaust temperature on the militaryplanes is apparently due to the cooling effectof a small amount of raw fuel.

Society of Automotive EngineersNew York CityApril 16, 1951

*o ~*

J. P. RUTHERFOORDApparatus DepartmentSTREET LIGHTING: Kansas City, working withthe Kansas City Power & Light Company, hasalmost completed a postwar relighting pro-gram. By using modern, efficient, highlyeffective equipment, the total number ofluminaires on Kansas City streets has beenreduced from approximately 15,000 under theold system to about 13,500 under the new.The total effective lumens, however, have

been increased from approximately 11,500,000under the old system to approximately 49,-000,000 under the new system. In spite of thistremendous increase in effective lumens on thestreet, the annual street lighting bill to thecity has increased from $552,000 per year toonly $626,000 per year.

If you evaluate that in terms of lumens onthe street, the people of Kansas City werepaying approximately $47.53 per 1000 lumensunder the old system and are presently payingonly $12.80 per 1000 effective lumens underthe new system.

Rotary ClubWeymouth, Mass

July 24, 1950

G1o canN LC44Eoa Edi#sce uGENERALSELECTRIC

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SCIENCE, Vol. 113

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