Biographical encyclopedia
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646 [1018] HERTZS PRUNG SCHWARZSCHILD [1019] American Telephone and Telegraph Company for $390,000 (a bargain at the price), but in the days of its first devel opment, he had his hard times. At one point he was placed under arrest for using the mails to defraud, when he was merely trying to raise cash to finance this invention. Like many inventors he was not a particularly successful busi nessman. Frequently engaged in litiga tion, he lost fortunes as often as he made them. His triode, however, remained in un disputed command of the 90-billion- dollar electronic industry it created for a generation until Shockley’s [1348] tran sistor put it in the shade. In the early 1920s De Forest worked out a “glow lamp,” which could convert the irregularities of a sound wave into similar irregularities of an electric cur rent, which would in turn create similar irregularities in the brightness of the lamp filament. The filament brightness could be photographed along with a mo tion picture and the varying brightness of the sound track could then be recon verted into sound. In 1923 De Forest demonstrated the first sound motion pic ture and within five years “talkies” began to take over. All in all, De Forest was granted more than three hundred patents, the last in 1957 when he was eighty-four years old. Because of the invention of the triode, De Forest is sometimes called the father of radio and he wrote an autobiography with that title. However, few inventions have had so many fathers. [1018] HERTZSPRUNG, Ejnar Danish astronomer Born: Frederiksberg, October 8, 1873
Died: Roskilde, October 21, 1967 Hertzsprung, the son of a minor gov ernment official, was educated as a chemical engineer and worked in St. Petersburg from 1899 to 1901. He re turned to Copenhagen in 1902 as an am ateur astronomer and in 1909 he was ap pointed lecturer of astrophysics at Gottin gen because of the favorable impression his work made on Schwarzschild. Hertzsprung had first advanced the no tion of “absolute magnitude,” comparing the brightness of the stars by placing them, in imagination, at a standard dis tance of ten parsecs (“luminosity”), where a parsec is the distance at which a star has a parallax of one second, or 3.25 light-years. He went on to note the relationship of color and luminosity among stars as early as 1905. He specialized in photog raphy (doing good work in estimating stellar magnitude from photographs and in photographing double stars accu rately) so he published his notions in a journal of photography in a semipopular way. His article lay there unnoticed for nearly a decade. H. N. Russell’s [1056] independent discovery of the fact was announced more formally and as a result both astronomers share equally in the credit.
In 1911 Hertzsprung noted that the Pole star varied slightly in brightness and was a Cepheid and in 1913 he was the first to estimate the actual distances of some Cepheid variables. This, together with the work of Leavitt [975], allowed Shapley [1102] to work out the proper shape of our galaxy. Hertzsprung was full professor at Lei den in 1935. He retired in 1945 and re turned to Denmark to die in the fullness of his years, one of the patriarchs of sci ence. [1019] SCHWARZSCHILD, Karl (shvahrts'shild) German astronomer Bom: Frankfurt-am-Main, Octo ber 9, 1873 Died: Potsdam, May 11, 1916 Schwarzschild was the son of a pros perous Jewish businessman. He grew in terested in astronomy as a child, was en couraged by his culture-centered family, and wrote and published his first astro nomical paper (on the orbits of double stars) when he was sixteen. He studied at the universities of Stras bourg and of Munich, and received his 6 4 7
[1020] COOLIDGE
COBLENTZ [1021] Ph.D. summa cum laude in 1896. In 1901 he accepted a professorial position at Gottingen. Schwarzschild developed the use of photography for measuring the bright ness of stars, particularly of variable ones. As a result of using this technique, he suggested that periodic variable stars behaved so because of periodic tempera ture changes, and this led to the further work of Eddington [1085] on Cepheid variables. He volunteered for military service when World War I began and was serv ing on the Russian front with the artil lery in 1916 when he heard of Einstein’s [1064] work on general relativity. He was the first to offer a solution to Ein stein’s field equations, and he was the first to calculate gravitational phenomena in the neighborhood of a star with all its mass concentrated in a point. This was what came to be called a black hole a half century later, and the concept of the Schwarzschild radius as the boundary of such a black hole is still accepted. He died soon afterward of a rare metabolic disorder. Schwarzschild, throughout his working life, attached great importance to lectur ing and writing on popular astronomy. [1020] COOLIDGE, William David American physicist Born: Hudson, Massachusetts, October 23, 1873 Died: Schenectady, New York, February 3, 1975 Coolidge, a distant cousin of President Calvin Coolidge, graduated from Massa chusetts Institute of Technology in 1896 on borrowed money, then went to Ger many on a scholarship for graduate work, obtaining his Ph.D. summa cum laude at Leipzig in 1899. In 1905 he joined the General Electric Company where he remained till his retirement in 1944, eventually becoming director of research, and vice president. One of the great technological prob lems of the early twentieth century was that of finding a satisfactory fiber for use in electric light bulbs. Edison [788] had introduced carbon fibers, but these were brittle and difficult to handle. Some high- melting metal, in the form of wire, would be much better. Tungsten is the metal with the highest melting point (about 3410°C) but it is also brittle and there was no reasonable way of drawing it into wires. At least there wasn’t till Coolidge got to work. In 1909 he patented a technique for manu facturing ductile tungsten, which could be drawn out into fine wires, and it is such wires that, to this day, are to be found in light bulbs, radio tubes, and other devices. Coolidge also made use of a tungsten block as anode in an X-ray tube in 1913 and the resultant version (the “Coolidge tube”) shifted X-ray production from the laboratory into common use in in dustry and medicine. During World War I, in collaboration with Langmuir [1072], he developed the first successful submarine-detection sys tem. In World War H he was engaged in atomic bomb research at Hanford, Washington. He shared with Chevreul [448] the dis tinction of being a scientist-centenarian. [1021] COBLENTZ, William Weber American physicist Bom: North Lima, Ohio, Novem ber 20, 1873 Died: Washington, D.C., Septem ber 15, 1962 Coblentz, the son of a farmer, was graduated from Case Institute of Tech nology in 1900 and obtained his Ph.D. in 1903 from Cornell. In 1905 he founded the radiometry section of the National Bureau of Standards, which he then headed for forty years. He was particularly interested in radia tion beyond the visible spectrum and showed that different atomic groupings absorbed characteristic and specific wavelengths in the infrared. His instru ments were too crude to convert this finding into a method of analysis, but be fore he had ended his long life, the ad vance of technology had brought the in frared spectrophotometer into being.
[1022] HARKINS
STARK [1024] This measured and recorded the extent of absorption of different wavelengths in the infrared so that from the rise and fall of the inked stylus, the various atomic groupings in a given molecule could be detected with extraordinary delicacy and without damage to the molecule itself. [1022] HARKINS, William Draper American chemist
December 28, 1873 Died: Chicago, Illinois, March 7, 1951
Harkins was bom near the site where oil was first obtained by drilling, and his father was one of the pioneers in this field. Harkins obtained his Ph.D. at Stanford University in 1900, then trav eled to Germany for advanced work under Haber [977]. After teaching for some years at the University of Mon tana, he took a post at the University of Chicago in 1912 and remained there for the rest of his life. He grew interested in nuclear chemis try and showed daring foresight, predict ing the existence of the neutron and of heavy hydrogen. He was particularly in terested in the slight deviations from the whole number in the mass of atomic nuclei, introducing what he called the packing fraction, which signified the amount of energy consumed in packing the nucleons into the nucleus. He used Einstein’s [1064] equation relating mass and energy to show that if four hydro gen atoms were converted into a helium nucleus, some mass would be lost (saved in the packing, so to speak), which would appear as energy. He suggested this as the mechanism whereby stars gained energy and this has turned out to be essentially correct. The hydrogen-to-helium conversion is, in es sence, the basis for fusion power and the hydrogen bomb. The latter development, however, Harkins did not quite live to see. He was one of the first to consider the problem of the relative proportions of the elements in the universe as a whole, basing his calculations on considerations of nuclear stability, the more stable nu clei being the more common. [1023] ERLANGER, Joseph American physiologist
January 5, 1874 Died: St. Louis, Missouri, Decem ber 5, 1965 Erlanger, the son of a German immi grant, attended the University of Califor nia and graduated in 1895, having ma jored in chemistry. He continued his ed ucation at Johns Hopkins medical school where he received his medical degree in 1899. In 1900 he joined the physiology department of Johns Hop kins. He next went to the University of Wisconsin’s newly organized medical school as head of the physiology depart ment and there Gasser [1126] was one of his students. Finally he headed the physiology department of Washington University, St. Louis, in 1910 (keeping this position till his retirement in 1948). Gasser joined him there. In the 1920s they did their work on the electrical properties of nerve fibers. They achieved great delicacy of mea surement, not by making still more sen sitive detectors as Einthoven [904] had done, but by making use of Braun’s [808] oscillograph to amplify the cur rents detected. In this way they deter mined how different fibers conducted their impulses at different rates, velocity of impulse varying directly with the thickness of fiber. For their work Er langer and Gasser shared the 1944 Nobel Prize in medicine and physiology. [1024] STARK, Johannes (shtahrk) German physicist
15, 1874 Died: Traunstein, Bavaria, June 21, 1957
Stark studied at the University of Munich and joined the physics depart ment at Gottingen in 1900.
[1025] MARCONI
MARCONI [1025] He worked with the canal rays that had been discovered by Goldstein [811] and managed to observe a Doppler [534] effect in them in 1905. In 1913 he showed that a strong elec tric field would cause a multiplication in spectral lines. This is an analogue of the effect of a magnetic field, discovered by Zeeman [945]. The Stark effect could be explained by quantum mechanics and thus served as another piece of support for quantum theory. For his work Stark received the 1919 Nobel Prize in phys ics. Stark, like Lenard [920], was one of the few German scientists of note who wholeheartedly supported Hitler and his racial theories. He turned violently and irrationally against both quantum theory and relativity, spoke and wrote reams of nonsense about “Aryan science,” and was all the Nazis could hope for in a sci entist. He snapped vindictively at the heels of Sommerfeld [976] and Heisen berg [1245], terming them “white Jews.” He served as president of the Reich Physical-Technical Institute from 1933 to 1939 and was sufficiently active as a Nazi to be tried and convicted by a denazification court in 1947. He was sentenced to four years’ im prisonment, a far milder punishment than would have been true had he been in the judge’s seat. [1025] MARCONI, Marchese Guglielmo Italian electrical engineer
Marconi came of a well-to-do family and was privately tutored. He studied physics under well-known Italian profes sors but without formally enrolling in any university. In 1894 he came across an article on the electromagnetic waves discovered eight years earlier by H. R. Hertz [873] and it occurred to him that these might be used in signaling. By the end of the year he was ringing a bell at a distance of thirty feet. He made use of Hertz’s method of producing the radio waves and of a de vice called the coherer to detect them. The coherer consisted of a container of loosely packed metal filings, which or dinarily conducted little current, but which conducted quite a bit when radio waves fell upon it. In this way radio waves could be converted into an easily detected electrical current. Gradually, Marconi improved his in struments, grounding both the trans mitter and receiver, and using a wire, in sulated from the earth, which served as an antenna or aerial to facilitate both sending and receiving. In the use of the aerial he was anticipated by Popov [895]. As time went on, he sent signals across greater and greater distances. In 1895 he sent one from his house to his garden and later for the distance of a mile and a half. In 1896, when the Italian govern ment showed itself uninterested in his work, he went to England (his mother was Irish and he could speak English perfectly) and sent a signal nine miles. He then applied for and obtained the first patent in the history of radio. In 1897, again in Italy, he sent a sig nal from land to a warship twelve miles away, and in 1898 (back in England) he covered eighteen miles. By then he was beginning to make his system commercial. The aged Kelvin [652] paid to send a Marconigram to the even more aged Stokes [618] and that was the first commercial wireless mes sage. Marconi also used his signals to re port the yacht races at Kingstown Re gatta that year. He obtained a key patent (number 7,777) in 1900 and then, in 1901, Mar coni reached the denouement of his drama. His experiments had already con vinced him that the Hertzian radio waves would follow the curve of the earth instead of radiating straight out ward as electromagnetic waves might be expected to do. (The explanation came the next year from Kennelly [916] and Heaviside [806] as suggestions that were demonstrated to be correct by Appleton [1158].) For this reason he made elabo rate preparations for sending a radio sig nal from the southwest tip of England to 6 5 0
[1026] DEBIERNE
GOLDBERGER [1027] Newfoundland, using balloons to lift his antennae as high as possible. On December 12, 1901, he succeeded, to the openly expressed admiration of Edison [788] (though Rayleigh [760] seemed to think it was a fraud). This might be considered as good a date as any for the invention of radio, although it was still only useful for sending signals in Morse code. It was left to Fessenden [958] to facilitate the transmission of sound-wave signals on radio-wave car riers. In 1904 a demonstration of radio operation was a big hit at the St. Louis World’s Fair. In 1909 Marconi shared the Nobel Prize in physics with Braun [808] and in later years experimented extensively with the use of short-wave radio for signaling. He was in charge of Italy’s radio ser vice during World War I, and perfected the “radio beam’’ along which a pilot could fly blind. Marconi interested himself in politics, too. He served as one of the Italian dele gates to the peace conference that con cluded the war. After that, he was an en thusiastic supporter of Mussolini’s Fas cist government. In 1929 he was made a noble, with the rank of marchese, by the Italian government. Radio came to be used as the chief means of public entertainment until largely replaced a generation later by television. Private communications, how ever, required the privacy of the tele phone wire, particularly after the im provement in the process introduced by Pup in [891]. When Marconi died, he was given a state funeral by the Italian government. [1026] DEBIERNE, André Louis (duh- biehmO
French chemist Born: Paris, 1874 Died: Paris, August 1949 Debieme, a student of Friedel [693], was a close friend of Pierre and Marie Curie [897, 965] and was associated with their work. In 1899, for instance, he discovered the radioactive element ac tinium, as a result of continuing the work with pitchblende that the Curies had initiated. After the tragic death of Pierre Curie in 1906, Debierne helped Marie Curie carry on and worked with her in teach ing and research. In 1910 he and Marie Curie prepared radium in metallic form in visible amounts. They did not keep it metallic, however. Having demonstrated the met al’s existence as a matter of scientific curiosity, they reconverted it into com pounds with which they might continue their researches. [1027] GOLDBERGER, Joseph Austrian-American physician
(now Giraltovce, Czechoslova kia), July 16, 1874
17, 1929 Goldberger, the son of a Jewish immi grant, was taken to the United States at the age of six. He was educated in the City College of New York, and obtained his medical degree from Bellevue Hos pital Medical College in 1895. He entered the U. S. Public Health Service in 1899 and was sent to Cuba and Mex ico to investigate yellow fever and typhus, both of which he contracted. In 1913 he was caught up in the grow ing field of vitamin research and spent most of the rest of his life investigating pellagra, endemic in the southern part of the United States. Funk [1093] had spec ulated that pellagra might be caused by inadequate diet, and Goldberger and his associates noted that it struck wherever the diet was monotonous and limited and did not include much in the way of milk, meat, or eggs. Addition of these items to the diet relieved the condition. In 1915 he conducted a dramatic ex periment on prisoners in a Mississippi jail. Volunteers (who were promised pardons in return) were placed on a lim ited diet, lacking meat or milk. After six months they developed pellagra, which could be relieved by adding milk and meat to the diet. Goldberger’s study group went to great lengths to try to
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