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[974] HALE
HALE [974] In 1908 Landsteiner was appointed professor of pathology at the University of Vienna. After World War I, during which Austria-Hungary suffered a cata strophic defeat, Landsteiner left Vienna and went to Holland. In 1922 he was in vited to join the staff of the Rockefeller Institute for Medical Research (now Rockefeller University) in New York. He accepted, became an American citizen in 1929, and remained in the institute for the rest of his life. In 1927 his group discovered addi tional blood groups (M, N, and MN), which, while not important in connection with transfusion, were as useful as the first group in anthropological studies. Then in 1940 he was also involved in the discovery of the Rh blood groups, which proved to have a connection with a dis ease of newborn infants called eryth roblastosis fetalis. His work on blood groups tends to eclipse, in the public mind, his research on poliomyelitis. He was the first, in 1908, to isolate the poliomyelitis virus and was also the first to use monkeys as an experimental animal in polio re search. However, nearly half a century passed before a real weapon against polio was devised by Sabin [1311] and Salk [1393]. In 1930 Landsteiner was awarded the Nobel Prize in medicine and physiology for his discovery of blood groups. He re tired from his post at the Rockefeller In stitute in 1939 but kept on working any way, and suffered his fatal heart attack while at his laboratory bench. [974] HALE, George Ellery American astronomer Bom: Chicago, Illinois, June 29, 1868
Died: Pasadena, California, Feb ruary 21, 1938 Hale, the son of a manufacturer of el evators who had made possible the sky scrapers of Chicago, graduated from the Massachusetts Institute of Technology in 1890 and, after some work in Europe, organized the Kenwood Observatory in Chicago. There in 1889 he invented the spectroheliograph, a device that made it possible to photograph the light of a sin gle spectral line of the sun. Thus, he was able to photograph the sun by the light of glowing calcium, and the result was a clear indication of the distribution of cal cium in the solar atmosphere. Hale de tected calcium clouds he called flocculi. (In 1924 he modified the instrument to allow the sun to be seen by hydrogen light. This showed up the hydrogen-rich prominences in particular and the modified instrument is the spectrohelio- scope.) Hale also detected strong magnetic fields inside sunspots in 1908. This was the first association of magnetic fields with any extraterrestrial body, and it led to the Nobel prize work of Zeeman [945], To continue his studies, however, Hale felt the need of better observatories and larger telescopes. Hale was a persuasive gentleman and in 1892 talked a hard headed American street-car magnate, Charles Tyson Yerkes, into putting up the money for a large observatory to be built in Williams Bay, Wisconsin, about eighty miles northwest of Chicago. For it, Hale had Alvan Clarke [696] (who had bought the necessary glass discs for another job and had been stuck with them by a reneging university) build a 40-inch refracting telescope, the largest of the type built before or since. It was completed in 1897 and Yerkes was paid off in fame, for it is the Yerkes telescope at Yerkes Observatory. Hale was not satisfied. He went on to plan and have built a still larger tele scope on Mount Wilson, near Pasadena, California with the help of money from the steel magnate Andrew Carnegie. A 60-inch reflecting telescope was put into action there in 1908 and a 100-inch reflecting telescope in 1917, paid for by the Los Angeles hardware tycoon John D. Hooker. The latter was to remain the largest telescope in the world for a gen eration. However, Pasadena and, even more so, Los Angeles, were growing, and the night sky, illuminated by these cities, began to lose its sharpness. (During World War II the blackout of those 622 [975] LEAVITT
LEAVITT [975] cities enabled Baade [1163] to do great work with this telescope.) Hale, there fore, chose a site on Mount Palomar, about ninety-five miles southeast of Mount Wilson, where the destroying hand of man had not yet come, and de cided to build an even more monstrous telescope there. In 1929 he obtained a grant from the Rockefeller Foundation and began work. He did not live to see it completed, but in 1948 a 200-inch telescope was finally mounted after fifteen years of the most painstaking labor (with World War II introducing its own sort of trouble some delay). It is, very rightly, named the Hale telescope and it remains one of the largest telescopes in the world. The Soviet Union has constructed a 600-cen timeter (236-inch) telescope. The Mount Palomar Observatory is also blessed with a 48-inch camera of a type invented by Schmidt [1065], the largest devise of this sort in the world. It is, in its way, even more useful than the telescope itself. During World War I, Hale placed the National Academy of Sciences on a war footing, as the importance of science in warfare was coming to be realized. The prime accomplishment of the academy was the organization of methods of pro ducing helium from natural gas wells. At the time, helium was useful as a noninflammable buoyant gas for use in dirigibles—a gas only the United States could then produce in quantity. How ever, with dirigibles passing out of the picture before World War II, helium be came even more useful and important in connection with low-temperature devices. [975] LEAVITT, Henrietta Swan (lev'it) American astronomer Born: Lancaster, Massachusetts, July 4, 1868 Died: Cambridge, Massachusetts, December 12, 1921 Leavitt, the daughter of a minister, graduated from the school now known as Radcliffe College in 1892. She joined the staff of Harvard Observatory, under Pickering [885] in 1902. In her meticu lous determinations of stellar magni tudes, she discovered 2,400 variable stars, doubling the number known in her time. Her great moment came in 1912, when she was working in the observatory set up by Harvard at Arequipa, Peru. She was then studying the Magellanic clouds (named for Magellan [130]). These are large star collections lying out side our galaxy but not very far away as galactic distances go. All the stars in these clouds are roughly the same dis tance from us, since variations from point to point within the clouds are small in comparison with the total distance from us.
Leavitt was particularly interested in certain stars that displayed periodic vari ations in brightness. These are called Cepheids because the first one studied was in the constellation Cepheus. She noted in 1904 that the longer the period of light variation, the greater the average brightness of the star. In our own galaxy this relationship had been obscured because a short-period star of low brightness might be so close to us that it would appear brighter than a dis tant long-period star of high real brightness. In the Magellanic clouds, with all stars at about the same great dis tance from us, this source of confusion was absent. Even the nearest Cepheid is too far from us to make it easy to determine its distance by the usual parallax method first successfully used by Bessel [439], However, there were other methods and Hertzsprung [1018] used one to pin down a Cepheid. Once one distance was known, it became possible to learn the distance of the rest by using the period- luminosity curve set up by Leavitt and Shapley [1102]. By comparing the true brightness, as shown by the period of variation, and the apparent brightness, the distance could be worked out. The Cepheids offered the first method of determining really vast stellar dis tances and man’s knowledge of the uni verse was greatly enlarged in conse quence. A still more tremendous yard stick was soon to be established, how ever, by Hubble [1136]. 623 [976] SOMMERFELD HABER
[976] SOMMERFELD, Arnold Johan nes Wilhelm German physicist Born: Königsberg, East Prussia (now Kaliningrad, U.S.S.R.), December 5, 1868
1951
Sommerfeld, the son of a physician, studied at the University of Königsberg and, in 1906, succeeded to Boltzmann’s [769] post at Munich through Roentgen’s [774] influence. His primary interest was in X rays and gamma rays and it was he who set Laue [1068] to work on them. In 1916 he modified Bohr’s [1101] theory to allow the inclusion of elliptical orbits for electrons. In doing so he ap plied Einstein’s [1064] relativity theory to the speeding electrons. Thus both rela tivity and Planck’s [887] quanta found their place in the atom. As a result, one often speaks of the Bohr-Sommerfeld atom.
Sommerfeld, although not Jewish, vig orously opposed growing Fascism and anti-Semitism in Germany after World War I. When Hitler came to power, Sommerfeld was denounced and by 1940 was forced into retirement. He survived Hitler and the war, however. At the age of eighty-three, when stroll ing with his grandchildren, he was run down by an automobile. [977] HABER, Fritz (hah'ber) German chemist Born: Breslau, Silesia (now Wroclaw, Poland), December 9, 1868
29, 1934 Haber, whose mother died when he was born, could not bear to work in his father’s dry-salt business, and, like Emil Fischer [833], found that he much pre ferred chemistry. He studied under Hof mann [604] at the University of Berlin and eventually obtained his doctorate in that field in 1891. In 1898 he gained a professorial appointment at the Univer sity of Dahlem, near Berlin. He was drawn to the relatively new field of physical chemistry, established by men such as Ostwald [840] and Ar rhenius [894], He did work in elec trochemistry and in 1909 devised a glass electrode of a type now commonly used to measure the acidity of a solution by detecting the electric potential across a piece of thin glass. It is the most com mon and convenient method for quickly measuring what Sørensen [967] that very year was to begin calling pH. Haber was also interested in the chem ical processes in a flame such as that of the Bunsen burner. (Part of his educa tion had been under Bunsen [565].) It was the study of gaseous reactions under heat that led him to his greatest fame. In the early twentieth century, one of the outstanding problems that faced chemists was finding a practical use for atmospheric nitrogen on a large scale. Nitrogen compounds were essential in fertilizers and explosives but the best large-scale source of such compounds was in the nitrate deposits of the desert in northern Chile, a long way from the industrial centers of the world. Yet the atmosphere everywhere in the world was four fifths nitrogen and it formed an in exhaustible supply if only someone could learn to convert the elemental nitrogen into compound form cheaply and on a large scale. In the very early 1900s Haber investi gated the possibility of combining nitro gen and hydrogen under pressure, using iron as a catalyst, to form ammonia. Ammonia could then easily be converted into fertilizer or explosive. By 1908 he was convinced he had something and his work was thought sufficiently well of to earn for him the directorship of the Kai ser Wilhelm Institute for physical chem istry and electrochemistry in 1911. Bosch [1028] developed the Haber process into a practical method for fixing nitrogen, and in World War I this proved a lifesaver for the German ar mies. The British navy cut off all imports of nitrates and if imports had been the only source, it is estimated that Germany would simply have run out of explosives by 1916 and been forced to surrender. 624 [977] HABER
WILSON [979] However, the atmosphere was at Ger man disposal, thanks to Haber, and the Kaiser’s war machine never ran out of ammunition and fought with terrible effect for two more years. In 1918, with the German armies going down to defeat at last, Haber, for the scientific value of his researches rather than for their war time uses, was awarded the 1919 Nobel prize in chemistry. Many scientists from nations that had fought Germany de nounced the award. And yet the Haber process had uses other than those for war. Using the prin ciple of the process, Bergius [1098] worked out methods for hydrogenating coal to form useful organic compounds. Haber, an extremely patriotic (even chauvinistic) German, had labored un ceasingly during World War I on gas warfare, directing the first use of the poison gas chlorine in 1915 and that of the far worse mustard gas in 1917. Had Germany used the first gas attacks on the large scale that Haber’s work made pos sible, they might well have won the war. As a result of the conservatism and timidity of the German generals, the Al lies had their own poison gas in a short time and the weapon was neutralized. After the war, Haber attempted to pay off the huge indemnity that had been laid upon Germany (which was never paid anyway) by isolating gold from sea water. In this, he failed. In 1933 Hitler came to power, and Haber faced an unexpected peril. One might have thought that, having saved the German armies in World War I, hav ing organized their gas attacks, having labored for years to pay off reparation, he might have been recognized as a Ger man of Germans. But he was lewish, and he was therefore forced to leave his post by the very ones who, having driven Germany to defeat in one war despite all that Haber could do, were destined to drive her to far worse defeat in a far worse war. Haber left for England but apparently did not like the land of the old enemy of the first war. Determined not to spend the winter there, he set out for a re search institute in Palestine but had a heart attack in Basel and died, just a few miles from his beloved—and ungrateful —homeland. [978] ABEGG, Richard Wilhelm Hein rich
German chemist Bom: Danzig (now Gdansk, Po land), January 9, 1869 Died: Köslin (now Koszalin, Po land), April 3, 1910 Abegg obtained his doctorate at the University of Berlin in 1891 and, for a time, worked as assistant to Nemst [936]. He was appointed professor of chemistry at the University of Breslau in 1897. He began to concern himself shortly afterward with the effect on chemical valence of the new electronic view of the atom. It seemed to him that the configura tion of electrons in the inert gas atoms (two in the outermost electron shell of helium—to use later terminology—and eight in those of the others) was particu larly stable. An element like chlorine that possessed one electron short of the desired eight tended to accept one, while an element like sodium that possessed one over, tended to give it up. A sodium atom would transfer an electron to a chlorine atom, forming a positively charged sodium ion and a negatively charged chloride ion and the two would hold together by electrostatic attraction. In this way a chemical reaction became the transfer of electrons and chemical bonds became the attraction between op posite electric charges. Abegg died in a balloon accident while still a young man and did not live to see his notions extended by a series of chem ists, beginning with Lewis [1037]. [979] WILSON, Charles Thomson Rees Scottish physicist Bom: Glencorse, Midlothian, February 14, 1869 Died: Carlops, Peeblesshire, No vember 15, 1959 Educated in Manchester, where his family had moved on the death of Wil 625 [979] WILSON
LEVENE [980] son’s father, a shepherd, in 1873, Wilson entered the field of meteorology and in 1895 began the study of clouds. This was to lead him in most unexpected di rections. Wilson, fascinated by the clouds on top of Ben Nevis (a Scottish peak nearly a mile high and the highest in Great Britain), tried to duplicate the effect on a small scale, while working in J. J. Thomson’s [869] laboratory at Cam bridge. He allowed moist air to expand within a container. The expansion low ered the temperature of the air so that not all the moisture could be retained, the excess coming out as water droplets to form a mist or cloud. The droplets of the cloud formed about the dust particles in the air, for if Wilson went to the trouble of using dust free air, the cloud did not form easily. (Work of the same sort was to lead Schaefer [1309] a half century later to attempts to control weather.) Dust-free moist air remained supersaturated upon expansion and cooling, and clouds did not form until the degree of supersatura tion had reached a certain critical point. In the absence of dust, Wilson believed, clouds must form by condensing about ions in the air. The electrical charge of those ions could serve as nuclei whereas ordinary neutral molecules could not. As soon as Wilson heard of the discov ery of X rays by Roentgen [774] and of radioactivity by A. H. Becquerel [834], it occurred to him that ion formation as a result of such radiations might bring about more intensive cloud formations in the absence of dust. This did indeed hap pen and Wilson’s theory of condensation about ions was thus proved. Wilson experimented for a decade and found that not only did water droplets form about the ions produced by ener getic radiation and by speeding particles, but the radiation and particles left a track of such ions as they moved. This track became visible in the form of water droplets that appeared when the chamber was expanded. Charged parti cles, in particular, left useful tracks, for the tracks curved when the chamber was subjected to a magnetic field and the na ture of the curve showed whether the charge was negative or positive and how massive the particle was. The tracks in dicated collisions of particles with mole cules or with other particles and offered a guide to events that took place during and after the collision. By 1911 the Wilson cloud chamber was perfected and offered a way of mak ing the events of the subatomic world visible to the eye in easily interpretable form. For years it proved an indis pensable adjunct to nuclear research. Blackett [1207] eventually improved the cloud chamber and Glaser [1472] de vised a first cousin to it, a generation later, in the form of the bubble chamber. But Wilson’s work was the original inspi ration, and the rest was commentary. Wilson received the 1927 Nobel Prize in physics for his cloud chamber. Its usefulness is further attested to by the fact that Blackett and Glaser earned sim ilar prizes for their improvements. [980] LEVENE, Phoebus Aaron Theo dor Russian-American chemist Born: Sager, Russia, February 25, 1869
Died: New York, New York, September 6, 1940 Levene’s unusual first name is an at tempt at adaptation. Levene, bom of a Jewish family, originally had Fishel as a first name. For use among Russians, after the family had moved to St. Peters burg in 1873, the Russian name Fyodor was adopted. Then, when the family emigrated to the United States in 1891, it became Phoebus, keeping the initial “f ’ sound. Levene’s medical education had been interrupted by the emigration. He re turned to Russia, completed the course, got his degree, and came to the United States again in 1892. After attending courses in chemistry at Columbia University, he decided to abandon medicine for chemistry and went abroad again to study under Ger man chemists such as Emil Fischer [833] and Kossel [842]. From Kossel he caught an interest in nucleic acids that Download 17.33 Mb. Do'stlaringiz bilan baham: 
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