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A "STARLIGHT" TUBEA " STARLIGHT " tube, it is called, a new super-sensitive

electronic tube smaller than a 25-watt incandescent lightbulb, can be used to measure accurately the feeble quan-tity of electricity in the light of a star many million-million miles away. It has, however, very practical essen-tial wartime uses in the electro-chemical analysis of metalssuch as steel, and the detection of impurities in highexplosive compounds.

The new tube and its development were described atthe New York meeting of the Institute of Radio Engi-neers by William A. Hayes, of the Westinghouse Electricand Manufacturing Co., who is responsible for its presentdevelopment.

The minimum amount of electric current which the tubecan measure, one one-hundred-trillionth (1/100,000,000,-000,000) of the electric energy in the light from anaverage home reading lamp, actually is less than theminute electric current in the dimmest starlight.When astronomers seek information concerning changes

in a planet 's direction, speed or other characteristics,they hitch the tube, which is attached to a photoelectriccell, to the "eye" end of an observatory telescope. Onthe basis of the starlight readings, the distance betweenthe earth and the stars is determined by trigonometriccomputation.

The sensitivity of the tube, which must be operated intotal darkness to keep ordinary daylight from energizingthe grid, is derived from its unorthodox design and con-struction. Glass " pants-legs " are tailored around thestiff metal wires which support the tube's internal struc-ture to prevent stray electrons from getting lost. Func-tioning like a lightning rod, a tiny tungsten wire is spot-welded inside the tube and pressed against its side tocatch unwanted electric charges that might affect itsaccuracy.

A simple electronic tube contains a wire filament thatshakes loose electrons when heated, a metallic mesh calleda grid that acts as a control gate through which electronsmust pass, and a plate that collects the electrons. In thenew starlight tube the roles of the plate and the grid areinterchanged; the grid functions as the plate and theplate as the grid.

ITEMSA TINY floating magnet, that remains in the air without

visible means of support over a lead plate cooled to atemperature only a few degrees above absolute zero, itselfcreates, it would seem, the power that holds it aloft. Theprobable explanation is that the magnetic field of themagnet sets up incessant induction currents in the lead,which, in turn, repel the magnet. This ability, in a ferro-nickel magnetized bar one centimeter long, was recentlydiscovered by scientists in the Soviet Union and is re-ported by a corresponding member of the USSR Academyof Sciences. In the experiment, the lead plate had beencooled to 269 degrees below zero Centigrade, approxi-mately four degrees above absolute zero. When the tiny

VoL. 101, No. 2617

magnet was thrown on the plate it bounced into the air

and remained floating until the temperature of the platerose three degrees, when it settled on its surface. This

action is dependent upon the very low temperature towhich the lead was subjected. It has been known for

years that at very low temperatures the electrical re-

sistances of some metals drop very greatly. When cooled

to this condition the metal is said to be superconductive.Lead becomes superconductive at 266 degrees below zero

Centigrade, and mercury at 269 degrees. A current

started by an electromotive force in a superconductivelead ring continues to flow for hours after the startingforce is removed.

ABOUT the size of a quart milk bottle and mounted on

the instrument panel of a B-29 Superfortress, the newair position indicator gives continuous readings of lati-

tude and longitude as the heavy bomber executes its mis-

sion to Tokyo. This is the first device to give such

readings in the history of navigation on the sea or in

the air. Developed by the Eclipse-Pioneer division of

Bendix Aviation Corporation, with the cooperation of theAir Technical Service Command at Wright Field and theNavy Department, the device eliminates the need for thenavigator to work for hours with charts, basic naviga-tional reference books, star-sighting sextants, and otheraids to navigation to calculate the position of his airplanein flight. The navigator of a B-29 can pinpoint his posi-tion on the map and keep the plane on the skyroad to anyenemy target, by referring to two needles on a small in-

strument panel dial of the air position indicator markedoff in degrees of longitude and latitude. This same dialalso gives him a continuous record of nautical miles flownand indicates the correct compass heading of the plane.

PATIENTS with severe streptococcus sore throats startto improve within 8 to 12 hours after the first injec-tion of penicillin and may be well within 24 hours, Armymedical officers found in studies reported in the Journalof the American Medical Association. Unless the pa-tients continued to get penicillin treatment for six days,however, they suffered relapses. The greater effective-ness of penicillin over sulfadiazine in throat infectionswith hemolytic streptococci is stressed in the report byMajor Norman Plummer, Miss Dorothy Rhoades Duersch-ner, Major Harold Draper Warren, Captain Francis T.Rogliano and Captain Ruell A. Sloan. "It should beused without delay in any serious, progressive hemolyticstreptococci infection," they advise. The most strikingfinding, they point out, was the disappearance of the strep-tococei from the nasopharynx within 24 hours. Thisraises a number of questions such as whether it is possiblecompletely to eradicate the streptococci from the bodyand what effect this would have on the course of the dis-eane and the development of rheumatic fever or kidneydisease as complications of strep sore throat. The studydoes not answer these questions, though it gave "someindication that complications of this disease can be pre-vented and effectively treated."

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12 SCIENCE-ADYI.RTISEMENTS

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UseD~ WERTHEIMIntroductory Organic Chemistry

By E. WERTHEIM, PH.D.Professor of Organic Chemistry, University of Arkansas

While the purpose of this book is to teach organic chemistry, it displays an interest in thevaried fields in which the subject is to be applied. This is demonstrated by the type ofillustrations.used, by the discussions of the uses of compounds and in the selection of thematerial presented. Teachers of domestic science will be interested in the ample coverageof such topics as fats, oils soaps, sugars, proteins, vitamins, hormones, digestion, metabol-ism, foods and dietary necessities. The book is also of interest to students in home eco-nomics and to nurses.82 Illus., 482 Pages. $3.00

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By G. AuWT Hid, PH.D.,Professor of Organic Chemistry, Wesleyan University,and LouIsE KELEY5 PH.D.,Professor of Organic Chemistry, Goucher College

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.12 SCIENCE-ADVPBTISEMENTS voil lol, No. 2617

SCIENCE-ADVERTISEMENTS

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The first of a series of three volumes, this book gives a circuits. The physical and mathematical essentials ofsystematic introduction to those basic concepts of elec- electrodynamics are logically developed and criticallytromagnetism that are fundamental in the study of discussed for the purpose of application to engineeringelectromagnetic waves, antennas, electromagnetic horns, problems. All concepts are introduced in their mostwaveguides, and ultra-high-frequency and microwave general form, and are defined systematically.

INTRODUCTION TO MICROWAVESBy SIMoN RAMO, General Electric Company. 142 pages, 5i x 84, 121 illustrations. $1.75

In this book the author presents a relatively nonmathe- cavities and wave guides, etc. The text correlates micro-matical description of the physical basis for all micro- waves with lower frequency electricity in simple lan-wave phenomena, including transit-time electronics, ve- guage, with a large number of explanatory diagrams.locity modulation, radiation, transmission lines, resonant The qualitative discussions are an outstanding feature.

METEOROLOGY. A Practical Course in WeatherBy GEORGE J. BRANDS, Pan American Airways System. 235 pages, 54 x 84, 73 illustrations.$2.50

Here is a text that meets the requirements- of those who a particular topic in concise form. The lessons are soneed a special knowledge of meteorology in its applica- arranged that the principles are thoroughly understoodtion to their work, for safety, economy, and efficiency. before the student attempts the practice of weatherEach lesson, consisting of text and examination, covers forecasting.

WORKBOOK IN ELEMENTARY METEOROLOGYBy FREDERICK L. CAUDLE, United States Naval Academy. 85 pages, 8 x 104, 23 illustrations.$1.00

This workbook provides beginning students with care- developing the skills needed to use meteorology success-fully planned material covering all important topics of fully in aviation and in many other fields of occupa-the meteorology course. It reviews principles and tests tional life. Covers stability, air masses, fog, localthe student's ability to apply them to new situations, weather signs, the radiosonde, thunderstorms, etc.

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FzBRUARY 231 1945 13

14 SCIENCE-ADVERTISEMENTS VOL.

-~S£(aIdc(amet 7eze!4THE EARTH AND MANBy D. H. DAVIS

"A fascinating presentation of the subject that is worth the at-tention of every geography teacher.'"'-Amer. Geographical So-ciety of N. Y. "The best book available in its field.'"'-Annalsof the Amer. Academy of Political & Social Science. "A veritablemine of geographical knowledge . . . judiciously selected andpainstakingly authenticated.... An excellent book in everyway.' '-Economic Geography. Covers both physical and eco-nomic geography. For the introductory course in geography onthe college level. $4.25

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NATURE AND PROPERTIES OF SOILSBy LYON and BUCKMAN

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SCIENCE-ADVERTISEMENTS VOL. lo1, No. 261714

SCIENCE-ADVERTISEMENTS

SELSYN MOTORSare available at much less than production cost! Take early advantage of this oppor-tunity to purchase Selsyns from stock. When used in combination with one or moreidentical motors, angular displacements of the shaft of the master unit are reproduced inthe shafts of the controlled units. Selsyn motors have many applications ranging fromindicating the angle of bridges and lock gates, the levels of liquids and the direction andspeed of wind, to demonstrating the fundamentals of alternating current electricity inthe classroom. Made with three-pole, three-phase wound stators and two-pole rotors withwinding for connection to single phase A.C. Although originally designed for use on115 volts, 400 cycles A.C. (67 watts-53.6 inch ounces torque) these motors will operateon 15 to 25 volts, 60 cycles A.C. (approx. 10 watts at 17 volts) and on other frequencies.

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1a-FEBRUAP.y 23i 1945

16SINEAVRIEENSVLl0,N.21

The Catalog CornerPlease write directly to the company indicated for any publication you wish mentioning the bulletin number andSCIENCE. Publications are gratis unless otherwise noted.

SCIENTIFIC BOOKS AND PERIODICALS

Vertebrate Zoology (94) and Publications ofLearned Societies (95). Two catalogs from the bookshop of H. G. Fiedler. No. 94 lists books availablein the fields of mammals, reptiles, amphibians, fishes,birds and a supplement on fossil vertebrates. Backnumbers of 714 different journals, complete volumesor partial sets are described in No. 95. Prices for allmaterial with descriptions for each item. CatalogsSCS-94 and SCS-95. HENRY GEORGE FIEDLER, 31-33East 10th St. (6th floor), New York 3, N. Y.Saunders School and College Textbook Catalog.

The 1945 edition, containing 117 titles ranging fromanatomy to zoology with prices and outlines of con-tents for each book. Catalog 1945 SC0. W. B.SAUNDERS, West Washington Square, Philadelphia 5,Pa.Comstock Publishing Co. Latest catalog of this

press covering publications in the fields of bacteriol-ogy, botany, conservation, entomology, limnology,medicine and surgery, microscopy, nature study, nu-trition, ornithology, veterinary medicine and zoology.Catalog 1944 SC2. COMSTOCK PUBLISHING CO., INC.,124 Roberts Place, Cornell Heights, Ithaea, N. Y.

Cornell Books. Complete listing of current titlesof The Cornell University Press. Includes volumeson botany, chemistry, economics and statistics, educa-tion social sciences and history of science. Catalog1944 SC2. CORNELL UNIVERSITY PRESS, Ithaca, N. Y.

Reinhold Publishing Corp. The 1945 edition of"Let's Look It Up." 124 page catalog of books onscience, technology, engineering, architecture and re-lated subjects. Lists American Chemical SocietyMonographs in print and new titles in preparation for1945. Catalog 1945 SC2. REINHOLD PUBLISHINGCORP., 330 West 42nd St., New York 18, N. Y.

Intersclence Publishers, Inc. A complete listingof the scientific publications of this company and theiraffiliates, The Nordeman Publishing Company- andElsevier Publishing Co. Lists a wide range of titlesin advanced fields of chemistry, many for research andindustrial workers. Other subjects included aremathematics, engineering, geology, physics and medi-cine. Catalog 1945 SC2. INTERSCIENCE PUBLISHERS,INC., 215 4th Avenue, New York 3, N. Y.

EQUIPMENT AND SUPPLIES

Illuminated Magnifiers. A new assembly of mag-nifiers in a light weight portable case for laboratoryand field work is described in a 2 page leaflet. Theset contains 7-X, 20-X and 40-X magnifiers with builtin illuminating units operated by battery or electriccurrent. For use in the range between visual inspec-tion and high power microscopy; Leaflet 45-S SC2.R. P. CARGILLE, 118 Liberty Street, New York 6, N. Y.Laboratory Centrifuges. A catalog with illustra-

tions and descriptions of centrifuges, centrifugal dry-ers, bottle shakers and other equipment designed spe-cially for laboratory use. Featured is a portablerefrigerated centrifuge capable of controlling tempera-tures between 100 and 500 F. Other centrifuge unitsshown are for soils analysis, oil testing, blood plasma,

serum and chemical research. Catalog SC2. INTER-NATIONAL EQUIPMENT CO., 352 Western Avenue, Bosston, Mass.

Bio-Photometer. Measurement of the photochemi-cal phase of vision with references and illustrationsfrom Army and Navy applications. Describes byquestion and answer method the principles underly-ing the dark adaptation test. Gives details (withreferences from medical literature) of uses of the bio-photometer in such fields as obstetrics, gastroenterol-ogy, urology pediatries and human nutrition. Bulle-tin SC2. BIO-MEDICAL INSTRUMENT CO., ChagrinFalls, Ohio.Water Conditioning Equipment. An illustrated-

catalog giving detailed technical data on Cochraneequipment for water treatment. Blue prints of lay-outs, cut-away diagrams, installation pictures andspecification tables are used to show applications toproblems involving removal of undesirable gases,deaeration, water softening and controlling the flowof water. General Catalog SC2. COCExANE CoRP.,Philadelphia 32, Pa.

Synthetic Organic Chemicals. A loose leaf gen-eral catalog periodically brought up to date, detailingcommercially available synthetic organic chemicals.Specifications and properties for each chemical areoutlines in well-arranged tables and text. Presentuses and other potential applications are discussed.References to the literature are given for the morerecent synthetics. General Catalog SC2. NIACETCHEMICAL CORP., P. 0. Box 460, Niagara Falls, N. Y.

Resin Colloids. A twenty-two page illustratedbrochure outlines the theory of emulsions, dispersionsand solutions. Tables and text are based on patentliterature and manufacturing experience of the Com-pany and describes the characteristics and uses for alarge number of resin colloids. Included are manysuggestions for possible further research and presentmanufacturing applications in the fields of adhesives,the leather, paper and textile industries. BrochureSC2. AMERICAN RESINOUS CHEMICAL CORP., Peabody,Mass.New Industrial Chemicals. A new 16 page booklet

that summarizes the available technical data relatingto many of the new industrial products and the chem-istry behind the newer organic compounds. One ofthe features is a section on new fungicides preparedfrom Pyridylmercuric salts with a discussion on someof the problems encountered in mildew-proofing ofcork and felt, the preservation of leather and relatedproblems in the textile, leather and paint fields. Book-let 3496 SC2. THE MALLINCKRODT WORKS, SaintLouis 7, Mo.pH Control. The twelfth edition of a pocket-sized

manual on the subject of colorimetric pH determina-tion. Methods and techniques evolved in laboratoriesand test over a period of 25 years are described andillustrated. The booklet is also a complete catalog ofthe company's line of equipment for pH work. Theindex indicates that many special reports on researchin diverse fields are available on request. The ABCof pH Control. LA OTT CHEMICAL PRODUCTS Co.,Towson, Baltimore 4, Md.

16 VOL. 101,,No..2617SCIENCE-ADVERTISEMENTS

FEI3RUARY 23, 1945 SCIENCE-ADVERTISEMENTS 17

PLATES AND FILMS

for Spectrum AnalysisTj~HE Eastman Kodak Company makes a number of plates

and films which are suited to the various requirements ofspectrum analysis. One of the most recent of these products isEastman Spectrum Analysis Film, No. 2. It has good speed,moderate contrast, and medium resolving power and granular-ity. Its contrast and wave length characteristics are very uni-form throughout the spectral region A2400A-x4400A.

Particulars concerning this and other films and plates forspectrum analysis will be forwarded promptly upon request.

EASTMANResearch Laboratories

KODAK COMPANYRochester, N. Y.

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* |r 51ft~[ OF| w- | 4IP

Inorganic andOrganic Chemicals

Biological StainsSolutions

Chemical IndicatorsTest Papers

Write for copy of our catalog

The COLEMAN & BELL Co.Manufacturing Chemists: Norwood, 0., U.S.A.

251iversary Year

Aj~nniversary Ye'ar

1920-1945

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SCIENCE-ADVERTISEMENTSFEauAzY 23., 1945 .17

18 .~EC AVRIEET Vo.11 N.21

PSh.:coiormt ApMc Matriu Ca# Basic 3SpaaAoduI VA bdldu PfOr lantern

Knowledge---up to the minute

New facts; new developments, newchanges arise daily out of the swiftlymoving events in a world geared to warand war production..'-The Spencer Model VA Delineascope

is performing an invaluable service, be-cause, in addition to lantern slides, it-can project the printed page, charts,photographs, diagrams and even opaqueparts and objects. Visually, it keeps mil-itary, production and training groups,large and small, abreast of last-minute,cv;lCpmcts,; .- *--, A.. . .. .... .. . o ............. ...... Write us for information about thisdouble-duty projector.SpencerL.NS.COMPYBUFFALO, NSW YORXSCIENTIFIC INSTRUMENT DIVISION OF4ME3RIC.A.N, OPTICA;L COM PANY.-

80,IENCE...AD.VE9TIS.EMENTS..18 VoL.101, No. 2617