MAC ,14 CECEAVRIEET

vvvvvANevvvText of OutstandivvyvvgA New Text of Outstanding Importance

VY

THE INVERTEBRATESProtozoa through CtenophoraBy LIBBIE HENRIETTA HYMAN

American Museum of Natural History

MCGRA-HILL PUBLICATIONS IN THE ZOOLOGICAL SCIENCES

726 pages, 6 x 9, fully illustrated. $7.00THIS long awaited book is the first volume of a projected treatise covering in a comprehensive and

up-to-date manner the morphology, physiology, embryology, and biology of the invertebrates.

The viewpoint is strictly zoological; hence no particular emphasis has been given to symptoms andtreatments of parasitic infections.

As one of the major purposes of the treatise is to give an extensive account of the range of morpho-logical variation to be found within each group, the "type" method of presentation has been avoided.Concepts and ideas current in zoological teaching have been critically scrutinized in the light of theavailable facts and have been passed or rejected according to the weight of the evidence.

One of the outstanding features of the book is the large number of illustrations made, wherever pos-sible, directly from living or prepared material.

Protoplasm, the Cell, and the OrganismClassificationThe Acellular Animals-Phylum ProtozoaPhylum MesozoaIntroduction to the Lower Metazoa

Chapter HeadingsMetazoa of the Cellular Grade of Construction-Phy-lum Porifera, the Sponges

Metazoa of the Tissue Grade of Construction-theRadiate Phyla-Phylum Cnidaria

The Radiate Phyla-Phylum Ctenophora

Send for a copy on approval

McGRAW-HILL BOOK COMPANY, INC.

MARCH 1, 1940 SCIENCE-ABDVERTISEMENTS .9

330 West 42nd Street, New York, N. Y.? Aldwych House, London, WV.C.2

SCIENCE-SUPPLEMENT

SCIENCE NEWS(Science Service, Washington, D. C.)

RECORD HIGH PRESSURES(Copyright, 1940, by Science Service)

NEW world's record high pressures, as much as 3,500,000pounds per square inch, have been achieved by Dr. P. W.Bridgman in Harvard's physics laboratories through useof nests of high pressure vessels in which inside apparatusreceives outside support at critical parts.A piece of tool alloy, Carboloy, composed of tungsten

carbide and cobalt, was subjected to a compressive stressof between 200,000 kilograms per square centimeter(2,800,000 pounds per square inch) and 250,000 kg./sq. cm.

(3,500,000 lb./sq. in.) without fracture. Carboloy's crush-ing strength under normal conditions is not more than70,000 kg./sq. cm. (1,000,000 lb./sq. in.). The confiningpressure that made possible these new high pressures wasabout 25,000 kg./sq. cm. (350,000 lb./sq. in.).

Dr. Bridgman, in reporting his results to The PhysicalReview, also made known that under such extreme pres-sures, carbon in the form of a thin plate of crystal graph-ite is not converted to diamond at room temperature.Both graphite and diamond are carbon. There had beenhope that pressure alone might cause the formation ofdiamond out of the other form of carbon. "It is probablethat no pressure, however high, will accomplish the con-version at room temperature," Dr. Bridgman now con-eludes. Doubling of the pressure apparatus, as practisedby Dr. Bridgman, makes it possible to reach pressure con-siderably more than double because of the increase inintrinsic strength under hydrostatic pressure.A striking effect of the extreme high pressures on Car-

boloy was that, although under normal conditions it ishighly brittle and breaks with practically no plastic de-formation, under the confining pressures used by Dr.Bridgman the piston of this tough material was plasticallyand permanently shortened by 5.5 per cent. with no per-ceptible cracks.

SOME PAPERS READ AT THE NEW YORKMEETING OF THE AMERICAN

PHYSICAL SOCIETYA NEW suggestion that the sun's corona is formed by

the motion of matter driven out under the action of thesun's intense light was presented at the New York meetingof the American Physical Society by Professor FelixEhrenhaft, now of New York City and formerly head ofthe department of physics at the University of Vienna.Professor Ehrenhaft reported experiments in which mate-rial particles were allowed to fall slowly in a magneticfield. When bright light was shone on these particles theymoved quickly sideways along the magnetic lines of forcein the field. When the direction of the magnetic field wasreversed, the motion was reversed. When either the lightor the magnetic field was shut off the sideward motionstopped and only the pure motion of fall remained. Theseexperiments, Professor Ehrenhaft said, explain the sun'scorona by indicating that particles in the sun move out-ward along magnetic lines of force due to the action of

the sun's own light. He pointed out that the late Dr.George Ellery Hale, distinguished astronomer of MountWilson Observatory, long ago called attention, withoutexplanation, to the similarity between the solar coronaand the lines of force of a magnetized sphere.PROFESSOR EHRENHAFT also discussed measurements

which cast doubt on the long-held postulate of physics thatthe charge on the electron is the smallest unit in whichelectricity occurs. Still a third research announcementby Professor Ehrenhaft was that light can, under certainconditions, exert an attractive force on matter in contrastto its commonly-recognized repulsive effect. This effectmay have applications in explaining phototropism, thatproperty of plants to lean and turn so that they face thelight.A NEW means of measuring accurately the voltage gen-

erated by the new, giant electrostatic atom smashers wasdescribed by Drs. W. H. Wells, R. O. Haxby, W. E. Shouppand W. E. Stephens, of the Westinghouse Electric andManufacturing Company. The new calibration point isat 2,010,000 electron-volts of energy at which berylliumbegins to give off neutrons when it is bombarded withprotons (cores of hydrogen atoms). The work extendsand makes more accurate previous studies at the Univer-sity of Rochester. Similar success with proton bombard-ment of boron carbide, lithium and carbon atoms was alsoreported by Dr. Wells and his colleagues. "All of thesereactions, or thresholds, occur at a very sharp and definitevoltage," Dr. Wells explained, "and will consequentlyserve as a good interlaboratory voltage standardizationtable." The new results fit in with many other observa-tions made at the Carnegie Institution of Washington andat the University of Wisconsin on the gamma rays emittedfrom lithium and from fluorine. These findings, too, serveas valuable calibration points for the giant electrostaticgenerators with which scientists smash atoms in theselaboratories.

A NEW check on the enormous amount of atomic energyreleased when uranium atoms are split by neutrons wasdescribed at the closing meeting by M. H. Kanner andH. H. Barschall, of Princeton University. As heavyuranium splits it gives off two fragments. The energyof these splitter products has been measured at Princetonand found to be equivalent to 159,000,000 units of atomicenergy. Units of atomic energy are expressed in electron-volts. This value is in good agreement with measurementsmade by Dr. Malcolm Henderson, also of Princeton, onthe heating effect of uranium's fission. Dr. Hendersonhas previously reported 175,000,000 energy units liberated.Other reports to the physicists' meeting concerned ura-nium fission; one of the most intriguing of all problemsin science to-day because it offers at least the remote possi-bility that some day and somehow it may be possible toutilize the vast amount of atomic energy thus liberated insome practical way. Dr. Herbert L. Anderson, of Colum-bia University, described measurements on the resonance

10 VOL. 91, No. 2357

MARCH 1, 1940 SCIENCE-ADVERTISEMENTS 11

New and Practical MOSBY TextsPHYSIOLOGICAL ANDPATHOLOGICALCHEMISTRYThis volume, which considersthe role that chemical actionplays in health and diseases, isa serious attempt to give stu-dents who are just beginningthe study of chemistry a bookthey can readily understand.Part I follows closely the out-line suggested by the NationalLeague of Nursing Education.Part II contains informationregarded as essential by theLeague and in addition discussesEnzymes, Digestive Tract, Hor-mones, Vitamins, and Patholog-ical Chemistry.By L. EARLE ARNOW. 600pages, with Laboratory Experi-ments. Price, $3.50

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AN INTRODUCTIONTO SOCIOLOGY ANDSOCIAL PROBLEMSHere is a dual purpose bookintended primarily as a textfor the student nurse duringthe two courses, Sociology andSocial Problems. It may alsobe used as a reference workduring clinical or graduatework.The author has drawn exten-sively from current text andreference books on sociologyand social problems used incolleges, bearing in mind theneed for such a text as this inschools of nursing.By DEBORAH MacLURGJENSEN. 341 pages. Price,$2.75

EXPERIMENTAL PHARMACOLOGYAND MATERIA MEDICAVital information on drugs and their uses, togetherwith Materia Medica and Prescription writing, ispresented in this volume. By DENNIS E. JACK-SON. 906 pages, 892 illustrations, 55 color plates.Price, $10.00

DISEASES OF THE SKINThis new 2nd edition ties description and conceptsof disorders of the skin with general medicine andpathology. Text and illustrations have been in-creased. By R. L. SUTTON and R. L. SUTTON,JR. 1549 pages, 1452 illustrations, 21 color plates.Price, $15.00

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MARCH 1, 1940 11SSCIENCE-ADDVERTISEMENTS

SCIENCE-SUPPLEMENT

capture of neutrons by uranium. This is an importantmatter because the ease with which a neutron can be cap-tured by a uranium atom determines how easily a splittingof uranium atoms can be secured. His studies show thatneutrons having only 5 electron-volts energy are involvedin liberating energies which, for each uranium fission,amount to over 150,000,000 electron-volts.

THREE new forms of artificially radioactive indium,created by bombarding the rare metal with high-voltagex-rays, have been manufactured by a research group at theMassachusetts Institute of Technology. The discovery,reported to the American Physical Society, confirmed thefindings of Notre Dame physicists that high-voltage x-rayswould produce radioactivity. The artificially activatedindium made in that experiment had a half-life of fourhours, but a whole range of activities have been uncoveredfrom one with a half-life of 4 hours to one with a half-lifeperiod of only 12 seconds. Substances with short half-life periods are expected to be very valuable in the medicalapplications of these substances. The report was a sup-plement to a scientific paper on the high-voltage produc-tion of positive ion and electron beams with the giantelectrostatic generator of the Massachusetts Institute ofof Technology. The research was done by Dr. Robert J.Van de Graaff, Dr. Lester C. Van Atta, Dr. Chester M.Van Atta and Doyle L. Northrup. Evidence of the newactivities was detected with the generator operating at alittle under 1,000,000 volts, considerably lower than hadbeen expected, and the yield mounted rapidly as the voltagewas increased. Indium is a rare metal with propertiessimilar to aluminum. It is silver-white in color, softerthan lead and about the same weight as tin. It is foundchiefly in zinc sulphide or zinc blende ores.-ROBERT D.POTTER.

THE FIRST EXPLORING EXPEDITION TOANTARCTIC CONTINENT

A CENTURY of American leadership in Antarctic explora-tion was celebrated on February 23, at the hall of theAmerican Philosophical Society. The expedition was thatled by Lieutenant Charles Wilkes, of the U. S. Navy, whogathered geographic, meteorological and other scientificdata along 1,500 miles of Antarctica's desolate shoresduring the years 1838-1840.

Captain G. S. Bryan, U. S. N., stated that the expeditionwas authorized by the Congress, largely in response to de-mands from whaling industry for better maps and navi-gational information. There was Congressional opposition,then as now, to spending money for scientific research.Funds were cut, unsuitable ships had to be used, clothingand other stores were inadequate. Fortunately, however,the scientific instruments carried were excellent, and thenine scientists who constituted the technical personnel ofthe expedition did their work well, so that most of theresults obtained are still valid.Worthy of note also is the fact that the government

sought the advice of the then existing scientific organiza-tions in planning the expedition. Particularly active werethe American Philosophical Society, which had beenfounded by Benjamin Franklin in pre-Revolutionary days,

and the Academy of Natural Sciences of Philadelphia.An account of this phase of the expedition was given byDr. Edwin G. Conklin, vice-president and executive officerof the American Philosophical Society, and by Dr. JamesA. G. Rehn, corresponding secretary of the PhiladelphiaAcademy.Although the Wilkes expedition was the first to conduct

long exploration in the Antarctic region, and to prove thecontinental nature of the South Polar land mass, it wasnot the first to find land in the region. Honors for thataccomplishment go to another American, Nathaniel BrownPalmer, a Connecticut sealer, who found that part ofAntarctica nearest South America on November 18, 1820,and explored some 450 miles of the frozen coast duringthe following January. The work of this "Columbus ofAntarctica" was described by Colonel Lawrence Martin,chief of the division of maps, Library of Congress.Although it was long before the era of daily weather

reports, the meteorology of Antarctica was intensivelystudied and minutely reported by Lieutenant Wilkes, de-clared Commander F. W. Reichelderfer, chief of the U. S.Weather Bureau. Commander Reichelderfer also told ofthe expedition's permanent contributions to science, in theform of geomagnetic and gravitational data.The expedition did not confine its work entirely to the

Far South. After the work along the coats of Antarcticawas completed, Lieutenant Wilkes took his ships far upinto the Pacific, as far as the Puget Sound region and thecoasts of British Columbia. Various phases of this partof the long voyage are the subjects of papers by MaryE. Cooley, of Mount Holyoke College; Henry W. Fowler,of the Academy of Natural Sciences of Philadelphia, andProfessor John E. Hoffmeister, of the University ofRochester. The fishes brought back by the expedition arestill preserved in the U. S. National Museum.

Continuation of the program was devoted principally toaccounts of later polar expeditions, Arctic as well asAntarctic. A special feature was an address on "Glaciersof the Antarctic," given by Professor Laurence M. Gould,of Carleton College, who was senior scientist and second-in-command of the First Byrd Antarctic Expedition.

THE FISSION OF URANIUM AS A SOURCEOF ATOMIC POWER

A POWER house for potent neutron particles-a labora-

tory piece of equipment for the generation of these neutralatomic particles that are perhaps the best of all weaponswith which to bombard the elements and produce artificialradiocativity and transmutations-is what Professor En-rico Fermi, of Columbia University, sees in the new atomic

process of uranium splitting.Discussing for the American Society of Mechanical En-

gineers the fission of uranium and its possible applicationas a source of atomic power, Professor Fermi said that" The large release of energy by the reaction ... is prob-ably only one and very likely not the most important aspectof the problem. Far more important might eventuallyprove the production of radioactive materials and of neu-

trons in practically unlimited amounts, for medical, bio-logical and physical investigations .... Although there

VOL. 91, No. 235712

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MARCE 1, 1940 SOZENCE----.d:DVERTISEMENTST~ 13

SCIENCE-SUPPLEMENT

is only a chance of success on these lines the stake appearslarge enough to justify some gambling on the part ofscientists. "The "gamble" of which Professor Fermi speaks is the

success or failure of experiments testing whether uranium,in its splitting, gives off other neutrons which can splitother uranium atoms and so on in a chain reaction. Ifthis self-perpetuating kind of chain-reaction can be cre-ated and kept under control in scientific laboratories, thenone may expect all top-flight physical laboratories of thefuture to have uranium-fission neutron sources. All thatwould be needed would be a small supply of radium placedin a mixture of beryllium. This radium-beryllium sourcewould supply the initial neutrons for starting the uraniumfission just as the pilot flame on a gas stove starts the gasto burning.

Surrounding the radium-beryllium neutron source wouldbe water or paraffin to slow the neutrons and also the"fuel" of the process, cheap uranium oxide ore. To startthe neutron generator one would place the radium-beryl-lium source at the center of a container of the uranium.Once the chain reaction started this original source wouldbe removed. The uranium would undergo splitting withthe liberation of the desired neutrons. To stop the proc-ess would require only the insertion, by mechanical means,of sheets of cadmium metal which has the ability to cap-ture and stop the low-energy neutrons strongly.-RoBERTD. POTTER.

THE PROTECTION FROM FROST OF SMALLVEGETABLES

A TRANSPARENT "hotcap" for the protection of tenderyoung vegetable plants in northern latitudes has been de-veloped by Professor Albert E. Wilkinson, extensionspecialist in vegetable and landscape gardening at theUniversity of Connecticut. He tried them experimentallyin his own garden last year and now is urging their useby commercial and home gardners.The miniature hothouses are made from cellulose acetate

sheeting which can be purchased commercially. It is alsothe material from which the base of amateur moving pic-ture film is made. A triangular piece of the material isfashioned into a simple cone. The apex of the cone issnipped off to provide ventilation. A piece of wire bentinto a hook is then thrust into the ground through thisaperture and holds the cone in place. The hotcaps canbe made at home with no tools but shears, wire, wire cut-ters and paper clips to hold the edges of the material to-gether in the cone shape. The edges can be cementedtogether with liquid cellulose acetate instead of usingpaper clips.

Hotcaps are used to cover small plants of cabbage,broccoli, tomatoes or other vegetables that are susceptibleto frost. They may also be used over seedlings of melons,cucumbers, sweet corn or early squash, and make it pos-sible to plant these vegetables much earlier than wouldotherwise be possible.Paper has been used extensively for this purpose in the

.past and serves adequately to protect the plants from coldtemperature. The advantages of the cellulose acetate hot-cap are: It admits the sun's rays, hastening growth. It

permits the gardener to see whether the plant is develop-ing without removing the hotcap. With reasonable careit can be used for several seasons.

ITEMSSURPRISING numbers of slow mesotrons, atomic par-

ticles found in cosmic rays, were found during an airplaneflight that rose to 29,300 feet in order to take cloud-cham-ber photographs of cosmic rays, Gerhard Herzog andWiston Bostick, Ryerson Physical Laboratory of theUniversity of Chicago, report in The Physical Reviewissued recently. Hint of other particles being presentin the cosmic rays at these high altitudes is contained inpictures that show stronger ionizing particles which maybe protons, alpha particles or still heavier nuclei.

A CHEMICAL related to sulfanilamide, known as pheno-thiazine, has been found highly effective in the treatmentof several species of parasitic worms in livestock by in-vestigators at the U. S. Department of Agriculture. Assoon as manufacturers make suitable application to thesecretary of argiculture, it will be released as an ac-

cepted veterinary medicine. Phenothiazine first came intoscientific notice half a dozen years ago when it was foundto be highly toxic to insects and very slightly so to warm-blooded animals. This original research was carried outby L. E. Smith, of the Bureau of Entomology and PlantQuarantine. Investigations since then indicate that it isone of the most versatile chemicals brought to light inrecent years. In addition to its effectiveness against in-sects, worms and other cold-blooded forms of life, pheno-thiazine has been found to have marked fungicidal andbactericidal properties. In the latter field, it has beenused as an internal antiseptic in human medicine, in thetreatment of cystitis, pyelitis and allied diseases. Re-searches on the use of phenothiazine in human medicinehave been conducted by Dr. Floyd DeEds, of the StanfordUniversity School of Medicine, to whom a public servicepatent on this phase of its applications has been granted.

MIMOSA trees, whose bright flowers and delicate, feath-ery, gray-green foliage are a delight to winter sojournersin southern resorts, are menaced by a new disease, appar-parently caused by a soil-dwelling fungus. Little is knownabout the disease, except that it kills the trees very quicklyand spreads rapidly. Its center of distribution, reportsDr. George H. Hepting, of the U. S. Department of Agri-culture, is at Tryon, N. C., and dead trees have been foundas far north as Richmond, Va., and as far south as La-Grange, Ga. Diseases that may be early stages in tree-

killing epidemics are also being studied in willows, oaks,shortleaf pines, Monterey cypress and Douglas fir. Twodiseases menace the American elm, and the London planetree, favorite in cities because of its resistance to smoke,are under attack in centers along the Atlantic seaboard.Millions of dollars are being spent to save white pines fromblister rust. The persimmon, whose wood is unequaledfor golf club heads, will probably soon join the alreadyextinct native chestnut. America's trees are in greaterdanger than most Americans realize.

VOL. 91, No. 235714

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16 SCIENCE-ABDVERTIlSEMENTS~ VOL. 91, No. 2357

SCIENCE-ADVERTISEMENTS

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rSCIENCE-ABDVERTI~SEMENTSS VOL. 91, No. 235718