P'EBRUARY 21, 1941 SCIENCE-ADVERTISEMENTS

Oiddk-c/kz L-h4 rn Ph~c

Electromagnetic TheoryBy J. A. STRATTON, Massachusetts Instituteof Technology. International Series inPhysics. 615 pages, 6 x 9. $6.00

Postulating Maxwell 's equations from the outset, theauthor of this new book emphasizes dynamic rather thanstatic field theory. A mathematical formation of thegeneral theory is followed by a comprehensive investiga-tion of energy and stress relations. The properties ofstatic fields are then discussed and the rest of the bookis devoted to the propagation of plane, cylindrical, andspherical waves, the theory of radiation, and boundaryvalue problems.

The Modern Theory of SolidsBy FREDERICK SEITZ, University of Pennsyl-vania. International Series in Physics. 698pages, 6 x 9. $7.00

In this important book the author presents a survey ofthe theory of the properties of all types of crystallinesolids. While the book deals largely with recent de-velopments in the field, it includes a coordinated treat-ment of those parts of the older theoretical work whichare still valid. The book is unique in that it covers thetheory of all types of solids from a common viewpoint.Besides dealing with the theory of metals, the authortreats the properties of salts and other insulators aswell, showing the factors which account for differencesand similarities in all these materials.

Physics of the Air. New third editionBy W. J. HUMPHREYS, United States WeatherBureau (Retired). 676 pages, 6 x 9. $6.00

The revision of this well-known standard treatise onatmospheric phenomena retains the orderly arrangementof material and the clear, explicit explanations of factsand theories which were outstanding features of earliereditions. Humidity is discussed more fully than be-fore; the discussion of vertical distribution of tempera-ture is amplified and revised in accordance with thelatest observations; the treatment of evaporation is ex-

panded; and many other changes have been made tocover recent advances.

Weather Analysis and ForecastingBy SVERRE PETTSEN,stitute of Technology.$5.00

Massachusetts In-505 pages, 6 x 9.

Unique in scope, this distinctive book presents a com-plete, authoritative treatment of modern methods ofweather analysis and forecasting. The author discussesin detail the underlying theories and their applicationto weather charts and upper air charts and offers num-

erous examples of correct analysis and forecasts. Re-cent results in the fields of air-mass analysis, frontalanalysis, and isentropic analysis are included.

Applied X-rays. New third editionBy GEORGE L. CLARK, University of Illinois.International Series in Physics. 674 pages,

6 x 9. $6.00

Presenting X-ray as a practical research tool, espe-cially in industry, this book covers the entire science ofX-rays, integrating physics, chemistry, crystallography,genetics, biology, medicine, and industries of every kind.The present edition contains chapters on interpretationof X-rays diffraction patterns; measurement of inten-sity, measurement of quality; photochemistry, biologicaleffects of X-rays; etc.

Introduction to Electricity and OpticsBy NATHANIEL H. FRANK, Massachusetts In-stitute of Technology. 398 pages, 6 x 9.$3.50

This textbook, together with the second edition of theauthor 's Introduction to Mechanics and Heat, consti-tutes a two-volume series in physics for the introductorytechnical course. Introduction to Electricity and Op-tics gives a logical exposition of the fundamental prin-ciples, emphasizing field theory and the elementary ap-plication of these principles to circuits and to the

electrical, magnetic, and optical properties of matter.

The treatment is quantitative throughout and modern

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SCIENCE NEWSScience Service, Washington, D. C.

THE EARTH'S MAGNETISMSPEAKING at Philadelphia at a two-day meeting of the

American Philosophical Society commemorating the cen-tenary of the first American magnetic observatory, estab-lished by Alexander Dallas Bache, Dr. J. H. Dellinger,chief of the Radio Section of the National Bureau ofStandards, told of ways in which the earth's magnetismaffects wireless transmission."It has long been known," he stated, "that radio

transmission on the high radio frequencies is markedlypoorer between North America and Europe than overother transmission paths. A possible relation of the radioanomaly to the propinquity of the magnetic pole was sus-pected, but there were no data on which to base a positiveconclusion. Following a discovery that this disparityexisted at the broadcast frequencies also, a systematicstudy was begun in 1935 and is still in progress. Mea-surements have been made in Europe and in North andSouth America of the received intensities of broadcaststations in the other continents, each (northern) wintersince 1935."

Disturbances in the ionosphere, the complicated layermore than fifty miles high from which radio waves arereflected back to earth, are associated with the magneticstorms at lower levels. These, Dr. Dellinger stated,"increase the variability of radio transmission betweenNorth America and Europe much more than betweenSouth America and either North America or Europe.The ionospheric and magnetic storminess, moreover, isprevalent much more of the time in the more northerlyregions traversed by the radio waves between North Amer-ica and Europe. Thus this transmission path is far moresubject to the disturbing effects than the paths more

remote from the polar regions."Magnetic disturbances on the earth are closely con-

nected with the activity of the sun. In addition to theeffect of the general magnetic storminess, there is another.Dr. Dellinger described this as " a very sudden, relativelybrief perturbation occurring simultaneously throughoutthe day hemisphere, the effect being a maximum at thesubpolar point and a minimum in the polar regions; it isdirectly caused by a solar eruption."

Dr. L. V. Berkner, of the Department of TerrestrialMagnetism of the Carnegie Institution of Washington,explained how the various layers of the ionosphere are

measured by sending up radio waves and catching theirechoes. There are three main layers, namely: the E-layer,62 miles high; the F-1 layer at 140 miles and the F-2layer at 220 miles. At night, or when the sun is low, thelast two merge to form a single F-layer at a level of 155miles. Apparently corpuscles shot out from the sun dis-turb the F-layers in which, he stated, occur the chiefionospheric effects associated with magnetic storms.

A NEW HIGH VOLTAGE POWER LINEDEFENSE construction in and around Chicago will be

less likely to suffer from electric failure on account of

a new high voltage power line just completed. Detailsof the line, which is 147 miles long, and brings more than200,000 horsepower of electrical energy from coal fieldsin southern Illinois, were given at the Philadelphia meet-ing of the American Institute of Electrical Engineers byM. S. Oldacre and F. 0. Wollaston, of the CommonwealthEdison Company.

Special consideration, they reported, was given in de-signing and building this line to obtain reliable serviceand eliminate outages caused by the two worst enemiesof transmission lines-sleet and lightning-both of whichare quite prevalent and severe along this route. As aresult of study by engineers connected with the operationof existing transmission lines and also those of the elec-trical manufacturing companies, it is believed that thesolution of these two major troubles of transmission lineshas been obtained.

It has been found that when wind of sufficient forcestrikes sleet-covered wires, the wires will be lifted mo-mentarily in the same way as a kite or airplane, and thealternate rising and falling and the swinging of thewires causes them to appear to "gallop" and sometimescome in contact with one another. This will at leastinterrupt power service over the line if it does not causeactual burning or breaking apart of the wires. Commonpractice on important smaller lines is to put extra electriccurrent through the sleet-covered wires to melt the sleetaway before it becomes dangerous. The wire or cablerequired for this line was so large-one and one sixthinches in diameter-that it could not be heated suffi-ciently. Instead, extra-strong supports were providedand the wires placed farther apart than usual so thatthere is no chance of the wires "galloping" or swingingtogether.The elimination of lightning troubles on existing trans-

mission lines has been obtained by using sufficient in-sulators for the electric wires and by placing additionalwires above the electric power wires to intercept thelightning currents and direct them into the earth over

paths of very low resistance. On this new line the latesttype of high-strength insulators, nearly ten feet long,have been used and the intercepting wires, known as

" ground " wires, have been installed so that there ispractically no chance of a lightning flash to the electricwires.At the same meeting, two other Commonwealth Edison

Company engineers, H. E. Wulfing and T. G. Le Clair,told of some of the operating details of the new line.Though carrying 220,000 volts it is so arranged that,should a short circuit occur anywhere on the line or itsterminals, the switches at both ends will open auto-

matically and disconnect the line in one sixth of a second.One interesting feature in the operation of the line isthe use of radio waves on the transmission wires to per-form many essential functions. Radio as used in thismanner is known as carrier current and differs from spaceradio, commonly used in broadcasting, in that it is con-

VoI,. 93, NO. 24086

F 2CIENCE-ADVERTISEMENTS 7

A New Illumuination Devicefor MICROSCOPES

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fined to the transmission wires and is actually superposedon the 220,000 volt power current and does not radiateinto space. This carrier current radio has three distinctbands and is modulated to provide eight channels overwhich many diversified operations are performed. It isessential that the carrier current radio be in continuousoperation because it is the watchdog of this importanttransmission line. It is therefore arranged so that it isself-checking and, should the radio stop, an alarm isgiven to the operators in the stations.

NATIONAL DEFENSE USES OF NATURALRESOURCES

DR. IRA N. GABRIELSON, chief of the U. S. Fish andWildlife Service, at the opening session of the Sixth NorthAmerican Wildlife Conference at Memphis, pointed outthat national defense uses of irreplaceable natural re-sources must be guided by discretion, lest harm ratherthan good result.Our very zeal for strengthening America can lead us

into errors that have an exactly opposite effect, pointingout as past examples the ill effects of over-fishing of ourwaters and over-cutting of our timber lands during theemergency of 1917-18. The country is still suffering theconsequences of the mistakes made by honest but over-enthusiastic patriots in those tumultuous days.Even worse may be done to us by cold-bloodedly selfish

persons who place self-interest ahead of patriotism, andadvance the plea of defense promotion only as a Trojanhorse for selfish schemes of their own. Watch out forsuch things as efforts to cut priceless virgin timber outof national park areas, under the excuse that it is to beused for "defense." Dr. Gabrielson pointed out that"If this country is to continue to be a good place to livein, or to be one worth fighting for, we must use intelli-gently the resources of soil and water, and the productsof soil and water, not only in good times but in bad times,and in national emergencies as well as in normal times."In the course of his address, Dr. Gabrielson reviewed

the progress of the wildlife restoration program duringthe past five years. Land acquisition and refuge crea-tion have gone forward very well though much still re-

mains to be done. The same is true in the arrangementsfor cooperation with state anl local agencies, especiallyin basic ecological research. Costs of these programs are

defrayed mainly by persons and groups most interested,through sale of "duck stamps" and sales taxes on sport-ing arms and ammunition.Somewhat slower progress, though still fairly satisfac-

tory, was noted by the speaker in such fields as educatingthe public in the recognition of wildlife values, and in thepromotion of specific research programs where presentknowledge is weakest, especially in the study of theecology of water areas. Much more needs to be done,too, toward the restoration of fish and of fur-bearinganimals. Both of these were once among America's great-est natural resources, and intelligent action can do muchto restore them to a large degree of their former im-portance.By far the least satisfactory situation, Dr. Gabrielson

said, exists with regard to river and lake pollution. Good

progress in the setting up of municipal sewage disposalplants during the past few years is contrasted with virtu-ally no progress at all in getting rid of pollution due toindustrial wastes. Most industrialists, the speaker said,have proved stubbornly uncooperative, and he challengedsharply the right of any man to misuse publicly ownedwaters as his private sewers.-FRANK THONE.

SULFANILAMIDE AND RHEUMATIC FEVERINCREASED hope that sulfanilamide may prove the

means of preventing attacks of rheumatic fever appearsin a report to the current issue of the Journal of theAmerican Medical Association and in editorial commenton that report.A record of no attack of rheumatic fever among 55

patients while taking continuous sulfanilamide treatmentfrom November through June of each year between 1936and 1940 is announced by Dr. Caroline Bedell Thomas,Dr. Richard France and Dr. Franjo Reichsman, of theJohns Hopkins Hospital and University. During thesame four years, fifteen major attacks of acute rheumaticfever occurred among 150 patients not taking sulfanila-mide during the control period.Rheumatic fever is a wide-spread disease which seriously

damages the heart and leads frequently to early death.More than 900,000 persons in the United States are saidto suffer from rheumatic heart disease. It is the chiefcause of death among school children and is responsiblefor at least 30,000 deaths annually in the United States.The exact cause of rheumatic fever has not been dis-

covered. Infection with the beta hemolytic streptococcususually precedes attacks and this germ is thought to playa significant role in starting the disease. This germ isthe one over which sulfanilamide accomplished its earliesttriumphs, saving mothers whose lives were threatened bythis streptococcus during childbirth.

Because of these facts, sulfanilamide was tried as atreatment for patients suffering attacks of rheumaticfever. It was not successful in these cases and there wassome evidence that it might be dangerous. The Balti-more doctors, however, and Dr. A. F. Coburn and Dr.Lucile V. Moore, of New York City, decided to try it, notas treatment, but as a preventive of recurring attacks ofthe disease. Authorities generally agree that the patientwho survives his first attack of rheumatic fever wouldhave a good chance of living out a normal life span ifhe could be protected from these repeat attacks with theiradded injury to the heart.As early as 1939, doctors reported in Baltimore and

New York that major attacks of rheumatic fever did notoccur, or occurred in only one per cent. of patients givensulfanilamide prophylaxis during the winter and springmonths when streptococcus infections are most numerous.The present report of experience over four years adds tothe hope that sulfanilamide prophylaxis of rheumaticfever will prove successful.The~drug is given twice daily in doses smaller than

those used for treatment of disease. No serious toxiceffects were observed. The editor of the Journal of theAmerican Medical Association comments on the "hopefulpicture-" the report gives and adds: " The final evaluation

8 .VOL. 93, NO. 2408

FEBRUARY 21, 1941 SCIENCE-ADVERTISEMENTS 9

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FFBR.uARY 21, 1941 SCIENCE-ADVERTISEMENTS 9

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of this method of prevention awaits results obtained inlarge, carefully controlled series of young rheumatic sub-jects. In view of the wide-spread occurrence and thecrippling effects of rheumatic fever, it is to be hoped thatinterest in and support for such projects will be sufficientto permit a final evaluation of this promising lead in theprevention of rheumatic fever."

THE EXTRACTION OF ANTIGENS BYSOUND WAVES

SQUEEZING and shaking substances valuable in medicineout of cultures of disease germs by means of intense soundwaves is the biological feat that has been accomplishedby Dr. Leslie A. Chambers and Dr. Earl W. Flosdorf,of the University of Pennsylvania.The substances they obtain belong to the class known

as antigens. They are poisons secreted within the germs'bodies. Injected into the human body in suitably smallquantities, they may be used in provoking the formation,by our own tissues, of opposing substances known as anti-bodies, which defeat the germs if they attack later on.Or the antigens may be injected into the bodies of ani-mals, from which blood is later withdrawn for makingimmune serums for medical use.

Present methods of obtaining antigens involve heating,addition of chemicals, or other treatments that injure ordestroy certain of the more sensitively composed antigens.This is what the new method of Drs. Chambers and Flos-dorf is designed to avoid. Its treatment of the germsis strictly physical or mechanical, and it can be conductedat a low temperature.The foundation of their apparatus is a magnetized

metal tube, usually made of nickel, which is caused tovibrate extremely rapidly by flowing an alternating elec-trical current around it in coils. The sound waves thusset up may be either exceedingly shrill, or even so high-pitched as to be in the ultrasonic range, beyond reach ofthe human ear. In either case, they are made highlyintense.

Over the upper end of the metal tube a glass tube isfitted, with a leak-tight rubber joint. Into the chamberthus formed a culture fluid containing billions of germs ispoured. Then the current is turned on and the vibra-tions started. After the treatment has been continuedlong enough to get out most of the antigens (and inci-dentally, to shatter most of the germs), the process isstopped, and the liquid is first centrifuged and thenpassed through a fine porcelain filter, to remove all debrisand any of the germs that may have survived the treat-ment.The antigens are in the clear, germ-free liquid that has

passed through the filters. Some types of these antigensare so sensitive and unstable that they will spoil if keptfor only a couple of hours at temperatures a little abovefreezing. However, if the liquid is frozen at once andthe water evaporated out of the ice, the solid, dried resi-due, now consisting of concentrated antigens, can be keptfor a year or more.

Drs. Chambers and Flosdorf have obtained U. S. patent(No. 2,230,997) on their apparatus and process, on whichthey have assigned their rights to the University of Penn-sylvania.

ITEMSFISH in hatcheries, no less than infants in nurseries

and grown-ups at table, need a certain amount of bulkand roughage in their food. Experiments at CornellUniversity have demonstrated the virtues of what isperhaps the purest form of roughage known, for it mustbe completely indigestible. Cellophane, cut into fineshreds, is fed to the fish along with their other food.They eat it readily, and seem to thrive on it.HUNGARIANS are now eating ersatz meat, concocted

cheaply from "twelve garden plants and vegetables,"and Germany may borrow the idea for large-scale pro-duction, according to the Foreign Commerce Weekly. Putup as a powder, the meat invention is made edible byadding water, salt and bread, and can be cooked in ham-burger or sausage-cake style by adding butter, cream andspices. About 2.2 pounds of artificial meat are said tocontain 3,727 calories, and to consist of 40 per cent.carbohydrate and 22.3 per cent. white albumen. Thecost of four portions is said to be less than 20 cents.WRAPPING oranges and other citrus fruits in paper

treated with diphenyl, a method originated by Dr. Adal-bert Farkas, of the Hebrew University, Jerusalem, hasbeen used with marked success by citrus growers in NewSouth Wales. Losses of fruit in the treated wrapperswere from two thirds to three fourths less than losses incontrol lots of similar fruit kept in ordinary untreatedwrappers. Dr. Farkas was fromerly a member of thefaculties of the Technical College in Vienna and the Uni-versity of Frankfurt-am-Main. After leaving Germany,he was for a time at the University of Cambridge, En-gland.THAT starch may soon be made commercially from kafir,

a grain-yielding sorghum, is indicated by research workby J. W. Greene, assistant professor of chemical engi-neering at Kansas State College. It may be possible tostart this new industry within a few months if properprogress is made. The fact that kafir possesses starchas a component part has been known for years, but chem-ists have had difficulty separating it from the rest ofthe grain on a profitable scale for commercial use. Pro-fessor Greene and his research assistants have been inter-ested mainly in processing the starch and finding newuses and commercial application. Professor H. N. Bar-ham, of the department of chemistry, has been studyingthe properties of the starch.

THOUGH chemically the same as plaster of Paris, a newgypsum plaster, described at the meeting of the AmericanInstitute of Chemical Engineers, is about twice as strongas the old-fashioned article. In fact, it approaches Port-land cement in strength. The new product was announcedby E. P. Schoch and William A. Cunningham, of the Uni-versity of Texas. It is prepared by heating gypsum in amagnesium sulfate solution, whereas plaster of Paris andordinary wall plaster are made by the dry calcination orburning of gypsum. Experiments in a small pilot plantindicate, they stated, that it can be made at a cost of$8.82 per ton, a figure that may be reduced by large-scaleproduction. Probably the magnesium sulfate plaster willfind its chief application in wall board, tile and otherfactory cast products.

10 VoI.. 93, No. 2408

FEBRUARY 21, 1941 SCIENCE-ADVERTISEMENTS

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TLIHE usefulness of the Spencer Spectrometer is greatly in-creased by the available attachments.

The specially designed Spencer precision camera when used inplace of the telescope (as shown in the illustration) convertsthe Spectrometer into a Spectrograph. With it, a series ofspectra may be photographed on the same plate.Another attachment converts the Spencer Spectrometer intoa Bunsen Spectroscope for visual demonstrations and com-

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SCIENCE-ADVERTISEMENTS VOL. 93, NO. 240812