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701 [1101] BOHR
SHAPLEY [1102] everywhere. The concentration of scien tific talent in Copenhagen made it, for that period, almost a new Alexandria. When Hitler came to power in Ger many in 1933, Bohr took what action he could on behalf of his colleagues in that terrorized land, doing his best to get Jewish physicists to safety. (Bohr’s own mother was of Jewish descent but it is quite certain that Bohr’s gentle, humane soul required no self-serving motiva tion.) In 1939 Bohr visited the United States to attend a scientific conference and brought with him the news that Lise Meitner [1060] was about to announce Hahn’s [1063] view that uranium un dergoes fission when bombarded with neutrons (uncharged particles—hence the name—that Chadwick [1150] had discovered earlier that decade). This broke up the conference as scientists rushed home to confirm the Hahn Meitner suggestion. It was confirmed, all right, and events were put in motion that culminated in the atomic bomb. Bohr went on to develop a theory of the mechanism of fission, one in which the nucleus was viewed as behaving some thing like a drop of fluid. Bohr predicted that the particular isotope, uranium-235, discovered a few years earlier by Dempster [1106], was the one that un derwent fission and in this he was quickly proved right. Bohr returned to Denmark and was still there when Hitler’s army suddenly occupied the nation in 1940. In 1943, to avoid imprisonment (for he certainly did not cooperate with the German occupa tion), and at the urgent encouragement of Chadwick, he escaped amidst consid erable peril to Sweden. There he helped to arrange the escape of nearly every Danish Jew from death in Hitler’s gas ovens. On October 6, 1943, he was flown to England in a tiny plane, in which he nearly died from lack of oxygen. Before Bohr left Denmark he dissolved the gold Nobel medals of Franck and Laue [1068]—which had been given him for safekeeping—in a bottle of acid. (His own had been donated for Finnish war relief.) He went on to the United States, where until 1945 he worked on the atomic bomb project at Los Alamos. His anxiety about the consequences of the bomb and his desire to share the secret with other allies in order to secure inter national control at the earliest possible time roused the bitter anger of Winston Churchill, who was on the edge of order ing Bohr’s arrest. After the war, he returned to Copen hagen, precipitated the gold from the acid, and recast the medals. It was sym bolic of the passing of one evil, but an other had come, that of the threat of nu clear war. Bohr labored unremittingly on behalf of the development of peaceful uses of atomic energy, organizing the first Atoms for Peace Conference in Geneva in 1955. In 1957 he was awarded the first Atoms for Peace award. [1102] SHAPLEY, Harlow American astronomer
vember 2, 1885 Died: Boulder, Colorado, October 20, 1972 Shapley, the son of a farmer, had little schooling at first and worked as a re porter. He labored to save money and to study in order to make a university edu cation possible. In 1903 he enrolled at the University of Missouri, from which he graduated in 1910, and then obtained his doctorate at Princeton University in 1913 working under H. N. Russell [1056]. In 1914 he joined the Mount Wilson Observatory in California and in 1921 was appointed to succeed E. C. Pickering [784] as director of the Har vard Observatory, a post he held till 1952. He was professor emeritus at Har vard after 1956. Between 1915 and 1920 Shapley used the 100-inch telescope at Mount Wilson to make a particular study of the globu lar clusters. These are immense densely packed aggregations of stars, some con taining as many as a million member bodies. About a hundred such clusters
[1102] SHAPLEY
MINOT [1103] were known at the time. Far from being evenly distributed over the sky, they were concentrated in the direction of Sagittarius. One-third of them, in fact, occur within the boundaries of that one constellation. Shapley had at his disposal the Ce- pheid yardstick worked out by Leavitt [975] a few years earlier and he applied the period-luminosity curve to the Ce- pheid stars in each globular cluster in 1914. From the period of those Cepheids and from their apparent brightness, he could calculate their distances. In this way he determined the distance of the various clusters and found that they were distributed in a sphere, roughly speaking, about a center in the constel lation Sagittarius. (He also suggested that Cepheids varied through pulsations, or variations in diameter. This was fur ther worked out by Eddington [1085].) It seemed sensible to suppose that those globular clusters, if they assumed a spherical arrangement about some point, would do so about the center of our gal axy, and this center, judging from the ar rangement of the clusters, was 50,000 light-years from the sun. Shapley suggested this galactic model in 1918. (Later work by Oort [1229] reduced this figure to 30,000; and the smaller figure is now accepted.) Earlier astronomers, from Herschel [321] to Kapteyn [815], had assumed the sun to be near the center of our galaxy, since the Milky Way (the mass of faint stars seen in the direction of the long axis of the galaxy) was about equally bright in all directions. Shapley, how ever, pointed out that dark dust clouds (many of which are clearly visible in the Milky Way) obscured the bright center and left us with a clear optical view only of our own neighborhood in the outskirts of the galaxy. (A generation later, radio astronomy was to confirm this.) Shapley’s work, which triumphed over what was, to begin with, bitter opposi tion, was the first to present a picture of our galaxy that gave a relatively true idea of its size. All previous estimates had been far too small. And just as Copernicus [127] had dethroned the earth from its supposed position as cen ter of the universe, so Shapley deposed the sun from its supposed position as center of the galaxy. The latter discovery was less epoch-making, but it did mark the real beginning of galactic astronomy, a field soon considerably advanced by Hubble [1136]. After World War H, he was active in the cause of civil liberties and peace and clashed frequently with such obscu rantists as Senator Joseph McCarthy. [1103] MINOT, George Richards (my/- nut) American physician Born: Boston, Massachusetts, De cember 2, 1885 Died: Brookline, Massachusetts, February 25, 1950 Minot, the son of a physician, was educated at Harvard University as an undergraduate and a graduate student, receiving his medical degree in 1912. After work at Johns Hopkins he re turned to Boston in 1915, serving at Massachusetts General and Peter Bent Brigham hospitals, as his father, uncle, and grandfather had done before him. Minot was interested in blood disor ders and particularly in pernicious ane mia, in which the red blood corpuscle count declines progressively, with an in variably fatal end. In the early 1920s G. H. Whipple [1059] had reported ex periments in which liver in the diet had had a strong effect in raising red blood corpuscle counts in anemia (though pernicious anemia was not studied) and this set Minot to thinking. He had already decided that perni cious anemia might be a dietary defi ciency disease resulting from the lack of a vitamin, since it was always accom panied by a lack of hydrochloric acid in the stomach secretions. Perhaps digestion failed and less than normal quantities of a particular vitamin were absorbed. There seemed no harm in trying liver in the diet, since liver was known to be rich in vitamins. In 1924 he and his assistant Murphy 703 [1104] WILLIAMS
KENDALL [1105] [1154] began feeding pernicious anemia patients liver, and by 1926 forty-five of them were on such a diet. It worked amazingly well and pernicious anemia has been an eminently treatable disease ever since. In a way, Minot thus repaid a debt to medicine. He himself was a dia betic who would surely have died a quarter century earlier than he did had Banting’s [1152] isolation of insulin not come along just in time to save him. In 1928 Minot was appointed profes sor of medicine at Harvard Medical School and in 1934 he, Whipple, and Murphy all shared the Nobel Prize in medicine and physiology. Minot was quite right in suspecting a vitamin deficiency to be at the root of pernicious anemia. This was to be proved two de cades after his work by men like Folkers [1312],
[1104] WILLIAMS, Robert Runnels American chemist Born: Nellore, India (of Ameri can parents), February 16, 1886 Died: Summit, New Jersey, Octo ber 2, 1965 Williams, the son of a Baptist mission ary, was not taken to the United States till he was ten. He obtained his master’s degree at the University of Chicago in 1908, then spent some time teaching in the Philippine Islands. He returned to the United States in 1915, and his later years were spent chiefly at the Bell Tele phone Laboratories, from which he re tired in 1945. In the 1930s he brought to completion the effort, begun by Eijkman [888] and Funk [1093] a generation earlier, to iso late and identify the anti-beriberi factor (thiamin). In 1934 Williams perfected methods of isolating about a third of an ounce of the material from a ton of rice polishings. By 1936 he had worked out its molecular structure and proved that structure by synthesizing the compound. In the decades following, synthetic methods have enabled the United States to produce twenty-five tons or more of the vitamin each year. Synthetic vitamins have become big business, and depen dence on natural sources for thiamin and many other vitamins is no longer neces sary for those who choose to invest in vi tamin pills. [1105] KENDALL, Edward Calvin American biochemist
icut, March 8, 1886 Died: Princeton, New Jersey, May 4, 1972 Kendall was educated at Columbia University, gaining all his degrees there through his doctorate, which he obtained in 1910 with Sherman [1036] as one of his teachers. While working at St. Luke’s Hospital in New York in the early 1910s he grew interested in the thyroid gland. Starling [954] and Bayliss [902] had in troduced the hormone concept the previ ous decade and it seemed clear that the thyroid produced a hormone. In the late nineteenth century the thyroid had been shown to be responsible for the overall rate of metabolism of the body, so that the human engine raced, so to speak, when the thyroid was overactive and slowed to a crawl when it was underac tive. Surely this was done through the mediation of a hormone. In the 1890s the thyroid gland had been shown to contain unusual quanti ties of iodine, an element not previously known to occur as an essential compo nent of tissue, and over the next decade an iodine-containing protein, thyroglob- ulin, had been obtained from thyroid. It was Kendall’s intention to narrow down the search for the actual thyroid hor mone by breaking up the large thyro- globulin molecule and finding, if he could, an active fragment. In 1916 (by which time Kendall had joined the staff of the Mayo Foundation in Rochester, Minnesota) he achieved his aim and isolated what he called thyroxine. Over the next decade its structure was determined and found to be comparatively simple, that of a single amino acid. Furthermore, it was most closely related to the common amino acid, tyrosine, its most unusual charac 7 0 4
[1105] KENDALL
ROBINSON [1107] teristic being that its molecule contained four iodine atoms. Thyroid hormone became an impor tant item in the medical armory, along with the insulin isolated by Banting [1152] and Best [1218] the decade after Kendall’s feat. The hormone concept be came more than mere theory; it offered a route for practical therapy. The road of research led to other hor mone-producing glands and the adrenals long resisted the probing quest. The adrenal gland is an organ made up of two parts. The inner part, the medulla, manufactures epinephrine (adrenaline) and that was no problem, for Takamine [855] had isolated that even before the hormone concept was advanced. The outer part, the cortex, however, manu factured a wide variety of substances and the problem was to identify their structure and function. Work toward this end was done in Kendall’s laboratory and in that of Reichstein [1201] in Swit zerland.
During the 1930s Kendall isolated no fewer than twenty-eight different cortical hormones or corticoids, of which four showed effects on laboratory animals. He named the corticoids by letter and the four effective ones were compounds A, B, E, and F. Research in the corticoids received a strong stimulus during World War II. A rumor made the rounds that the Ger mans were buying up adrenal glands in Argentine slaughterhouses and that ex tracts of the glands were enabling Nazi pilots to fly and fight at heights of forty thousand feet. The rumor was untrue, but it helped push American investi gation of the adrenals and, in fact, give it top priority among medical problems. By 1944 Compound A was synthesized, and in 1946 Compound E was. Their molecular structures were proved in that fashion.
The importance of the corticoids in medicine (even if not in making super men out of Nazi pilots) was underscored shortly afterward by Hench [1188], one of Kendall’s collaborators, who success fully used Compound E in relieving the symptoms of rheumatoid arthritis. In 1950 Kendall, Hench, and Reichstein all shared the Nobel Prize in medicine and physiology as a result. In 1952 Kendall became professor of chemistry at Prince ton University. [1106] DEMPSTER, Arthur Jeffrey Canadian-American physicist Born: Toronto, Ontario, August 14, 1886 Died: Stuart, Florida, March 11, 1950
Dempster was educated at the Univer sity of Toronto. He went to Germany for advanced work, but World War I made it impossible for him to remain and in 1914 he moved to the United States. He became an American citizen in 1918, having earned his Ph.D. in 1916 at the University of Chicago. He became professor of physics at the Uni versity of Chicago in 1927. His work with the mass spectrograph (he built his first one in 1918) was second only to that of Aston [1051], In 1935 he discovered an isotope that Aston had missed, one that was destined to be the most famous isotope of all, the rare uranium-235. It was out of that achievement that within the decade and thanks to the work of men like Hahn [1063], Fermi [1243], and Oppenheimer [1280], the first nuclear bomb was to arise.
[1107] ROBINSON, Sir Robert English chemist Born: Bufford, near Chesterfield, Derbyshire, September 13, 1886 Died: Great Missenden, near London, February 8, 1975 Robinson, the son of an inventor and manufacturer, was educated at the Uni versity of Manchester with the original notion of entering his father’s business. His ambition soon soared beyond that, however. He obtained his doctorate in 1910, and in 1912 traveled far from home for his first professorial position, which was in organic chemistry at the University of Sydney in Australia. In 1915 he returned to England and taught
[1108] HILL
TRUMPLER [1109] at a number of schools, ending, in 1929, at Oxford. As the techniques of organic synthesis developed, the chemists’ quest ventured further and further up the slopes of complexity and reached the alkaloids. These are nitrogenous compounds, pro duced by plants, possessing molecular structures consisting of rings of atoms (including nitrogen as well as carbon) in rather complex relationships. As a whole, they are the most complicated “one-piece” molecules known to chem ists. The larger giant molecules, such as those of proteins and starch, are made up of individual units, indefinitely re peated, the individual units being smaller and far less complex than most alkaloids. The importance of the alkaloids, aside from pure curiosity as to their molecular structure, lies in their profound physio logical effects upon the animal body even in small proportions. These effects can be poisonous or, in proper dosage, stimulating or analgesic. They can con ceivably have any number of effects that can be put to good use. Nicotine, quinine, strychnine, morphine, and cocaine are all well-known alkaloids. Robinson studied the alkaloids pains takingly and his greatest success was to work out the structure of morphine (all but for one dubious atom) in 1925 and the structure of strychnine in 1946. The latter structure was later confirmed by Woodward [1416], who synthesized the molecule. Robinson was knighted in 1939 and served as president of the Royal Society from 1945 to 1950. Robinson did work also on steroids and on certain plant coloring matters called flavones. It was for his work on alkaloids, however, that he received the 1947 Nobel Prize in chemistry. [1108] HILL, Archibald Vivian English physiologist
September 26, 1886 Died: Cambridge, June 3, 1977 Hill was educated at Cambridge, where he was first interested in mathe matics, finishing third in his class in that subject. However, he studied under a man who had collaborated with Hopkins [912] in the discovery of lactic acid in muscle.
Influenced by his teacher, Hill investi gated the workings of muscles. He did not attempt to work out the chemical de tails of muscle action but, instead, aimed for the determination of the quantity of heat produced. This was difficult enough. The heat production was so small and so transient that its measurement had stumped the ingenuity of Helmholtz [631]. Hill made use of thermocouples, which swiftly and delicately recorded heat changes in the form of tiny electric currents, and adapted them for his pur pose with great patience and ingenuity. He could measure a rise of 0.003 °C during a period of a few hundredths of a second. He found as early as 1913 that heat was produced after the muscle had done its work, and he showed that molecular oxygen was consumed then, but not dur ing the muscle’s contraction. His results jibed exactly with those of Meyerhof [1095], with whom he shared the 1922 Nobel Prize in medicine and physiology. During World War II, Hill represented Cambridge University in Parliament, as an Independent Conservative, and was a member of the War Cabinet Scientific Advisory Committee. [1109] TRUMPLER, Robert Julius Swiss-American astronomer Born: Zürich, Switzerland, Octo ber 2, 1886 Died: Oakland, California, Sep tember 10, 1956 Trumpler, the son of an industrialist, after an education in Switzerland and in Germany (obtaining his Ph.D. in the lat ter country in 1910), came to the United States in 1915 and spent his professional career at the University of California, joining the staff of Lick Observatory, where he remained till his retirement in 1951. In 1930 he showed that the light of the more distant globular clusters was dimmer than was to be expected from Download 17.33 Mb. Do'stlaringiz bilan baham: 
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