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711 [1119] r u &C ka SUMNER
[1120] ing the age of the solar system and set ting that at its presently accepted figure of 4,600 million years. [1119] RUZICKA, Leopold Stephen (roo'zheech-kah) Croatian-Swiss chemist
slavia), September 13, 1887 Died: Zürich, Switzerland, Sep tember 26, 1976 Ruziika’s education and professional life was variedly Teutonic, for though of Slavic extraction, he was born in an area which at the time of his birth was part of the German-controlled nation of Aus tria-Hungary. RuZiCka attended high school in Germany and college in Swit zerland (where he became a citizen in 1917). He obtained his doctorate under Stau dinger [1074]. His first teaching position was at the University of Utrecht in the Netherlands and in 1929 he became a professor of chemistry at the State Tech nical College in Zürich. In the mid-1930s he synthesized sev eral of the sex hormones, but ten years earlier he had done something that, to theoretical chemists, was more startling. He had analyzed the active compounds in musk and civet, two substances very important in the perfume industry, and showed that they consisted of rings of atoms. But what rings! One contained sixteen carbon atoms, the other seven teen. This was quite startling as, for a half century or so, Baeyer’s [718] theory that rings composed of more than six atoms were too unstable to exist, had been generally accepted. Ruziika’s discovery paved the way for a more liberal and useful interpretation of atomic ring structures. Baeyer’s theory applied, strictly speaking, to rings of atoms in a single plane, but it was possible, after all, for rings of atoms to “pucker” out of the plane. For this and for his investigations of a class of com pounds called terpenes, the study of which had been pioneered by Wallach [790], Ruziika shared the 1939 Nobel Prize in chemistry with Butenandt [1265], who received it for his work on the sex hormones. [1120] SUMNER, James Batcheller American biochemist Bom: Canton, Massachusetts, November 19, 1887 Died: Buffalo, New York, August 12, 1955 In 1904, when he was seventeen, Sumner, the son of a well-to-do cotton manufacturer, suffered a serious accident while hunting and his left arm had to be amputated. Since he was left-handed, he had to retrain himself to use his right hand. He did that well, becoming an ex pert tennis player, for instance. Sumner became a chemist against the advice of his teachers, who thought that the fact he had but one arm would be a handicap (as indeed it would be if scientific research was purely a matter of dexterous fingering). Sumner persisted and attended Harvard, graduating in 1910 and obtaining his doctorate in 1914. He then accepted a position as as sistant professor of biochemistry at Cor nell University Medical College. His chief interest was enzymes, and at the time he began his researches the question of the nature of enzymes had been thrown into confusion. It had for a long time been assumed, without direct evidence, that enzymes were proteins. Willstatter [1009] had produced negative evidence to the effect that enzymes were
enzyme preparations that yielded no pos itive response to any test for protein he used. (The tests weren’t delicate enough.) In 1926 Sumner was extracting the en zyme content of jack beans. The enzyme involved was one that catalyzed the breakdown of urea to ammonia and car bon dioxide, so Sumner called it urease. In performing his extraction Sumner found that he obtained a number of tiny crystals that had precipitated out of one of his fractions. He isolated the crystals, dissolved them, and found he had a solu tion with concentrated urease activity. He prepared more crystals and found
[1121] MOSELEY
MOSELEY [1121] that try as he might, he could not sepa rate the enzyme activity from the crys tals. The crystals were the enzyme and all his tests further agreed on the fact that the crystals were also proteins. Urease, in short, was the first enzyme prepared in crystalline form, and the first enzyme shown incontrovertibly to be a protein.
The impression made at the time by the unknown Sumner against the evi dence presented by the Nobel laureate Willstatter was at first very small. In 1929, however, he traveled to Stockholm to work on urease with Euler-Chelpin [1011] and Svedberg [1097] and by 1930 the much more elaborate researches of Northrop [1148] on crystalline enzymes made it quite plain that Sumner was right and Willstatter was wrong. Sumner, in consequence, received the 1946 Nobel Prize in chemistry, sharing it with Northrop and with Stanley [1282], [1121] MOSELEY, Henry Gwyn-Jeffreys English physicist Born: Weymouth, Dorsetshire, November 23, 1887 Died: Gallipoli (Gelibolu), Tur key, August 10, 1915 Moseley’s father had been a naturalist on the Challenger expedition that had been the first to explore the ocean deeps, and was a professor of human and com parative anatomy. He died when his son was only four. Young Moseley’s bent, however, was not toward the life sci ences but toward physics. He studied at Eton and Oxford, to both of which he won scholarships. (He was one of the very few important scientists to have come from Oxford rather than Cam bridge. He chose Oxford in order to remain near his mother.) For a time he did research under Ernest Rutherford [996] where he was the youngest and most brilliant of Ruth erford’s brilliant young men. When Laue [1068] and the Braggs [922, 1141] demonstrated how X rays could be refracted by crystals, Moseley seized upon the technique as a manner of determining and comparing the wave lengths of the characteristic X-ray radia tion of the various elements, a type of ra diation Barkla [1049] had discovered a few years earlier. In doing so, Moseley clearly demon strated what Barkla had suspected: the wavelength of the characteristic X rays decreased smoothly with the increasing atomic weight of the elements emitting them. This Moseley attributed to the in creasing number of electrons in the atom as atomic weight increased, and to the increasing quantity of positive charge in the nucleus. (This nuclear charge was later found to be a reflection of the num ber of positively charged protons con tained within the nucleus.) This discovery led to a major improve ment of Mendeleev’s [705] periodic table. Mendeleev had arranged his table of elements in order of atomic weight, but this order had had to be slightly modified in a couple of instances to keep the table useful. Moseley showed that if it was arranged in order of nuclear charge (that is, according to the number of protons in the nucleus, a quantity that came to be known as the atomic num ber) no modifications were necessary. Furthermore, in Mendeleev’s table any two neighboring elements might conceiv ably be separated by any number of in tervening elements, for no minimum difference in atomic weights among the elements had been established. Working with the atomic number changed things completely, however. The atomic num ber had to be an integer, so that between iron, with an atomic number of 26, and cobalt, with an atomic number of 27, no new and undiscovered elements could possibly exist. It also meant that from hydrogen, the simplest known element at the time, to uranium, the most complex, only ninety-two elements could exist. Furthermore, Moseley’s X-ray technique could locate all the holes in the table representing still-undiscovered elements, and exactly seven such holes remained in 1914, the year Moseley developed the concept of the atomic number. In addi tion to all this, if a new element filling one of these holes was reported, Mose ley’s X-ray technique could be used to check the validity of the report, as was 713 [1122] VAVILOV
GOLDSCHMIDT [1123] done in the case of Urbain's [1002] re port on the so-called celtium, and of Hevesy’s [1100] hafnium. In this respect, X-ray analysis was a new and sophisticated technique for chemical analysis. It departed from old methods involving weighing and titration and used far more delicate methods in volving measurement of light absorption, of alteration in electrical potential, as in Heyrovsky’s [1144] polarimetry, and so on. Moseley’s work did not significantly alter Mendeleev’s table, in other words, but it certainly nailed the elements it contained into position. World War I had broken out at this time and Moseley enlisted at once as a lieutenant of the Royal Engineers. Na tions were still naive in their under standing of the importance of scientists to human society and there seemed no reason not to expose Moseley to the same chances of death to which millions of other soldiers were being exposed. Rutherford tried to get Moseley assigned to scientific labors but failed. On June 13, 1915, Moseley shipped out to Tur key and two months later he was killed at Gallipoli as part of a thoroughly use less and badly bungled campaign, his death having brought Great Britain and the world no good (except for what cold comfort could be obtained out of the fact that he had willed his money to the Royal Society). In view of what he might still have accomplished (he was only twenty-seven when he died), his death might well have been the most costly single death of the war to man kind generally. Had Moseley lived it seems as certain as anything can be in the uncertain world of scientific history, that he would have received a Nobel Prize in physics. Siegbahn [1111], who carried on Mose ley’s work, received one. [1122] VAVILOV, Nikolay Ivanovich (vah-veeluf) Russian botanist
1887
Died: Saratov, January 26, 1943 Vavilov, the son of an owner of a shoe factory, graduated from the Moscow Ag ricultural Institute in 1911. In 1913 he went to England, where he studied under Bateson [913], but returned to Russia with the outbreak of World War I. (An eye problem kept him out of the army.) Both in England and in Russia he worked on plant immunity and tried to explain it on an evolutionary basis. He searched for specific strains of wheat that were resistant to the various damag ing wheat diseases. He went further in attempting to produce new strains of grain by judicious crossing that would have various desirable characteristics. In doing this he made full use of Mendel’s [638] genetic laws, of course. This meant he fell afoul of Lysenko [1214], Vavilov had praised Lysenko’s early work, but Lysenko denounced Vav ilov’s adherence to Mendelism. Vavilov resisted and what might have been a scientific controversy became a political one when Joseph Stalin sided with Ly senko. Lysenko did not hesitate to take advantage of this: On August 6, 1940, Vavilov was arrested, accused of a vari ety of ridiculous charges, and sentenced to death. On second thought, the sen tence was reduced to ten years’ imprison ment; but in the turmoil of World War II he was evacuated to Saratov, was mal treated, and died. In 1955, after Stalin’s death, Vavilov was rehabilitated and posthumously hon ored, while Lysenko remains a symbol of scientific oppression. [1123] GOLDSCHMIDT, Victor Moritz Swiss-Norwegian geochemist
ary 27, 1888 Died: Oslo, Norway, March 20, 1947
Goldschmidt’s father was a physical chemist of considerable reputation and obtained a post as professor of chemistry at the University of Oslo, succeeding Waage [701] in 1905. He brought his family with him and arrived shortly be fore Norway succeeded in establishing its independence from Sweden. In a few 714 [1124] STERN
FRIEDMANN [1125] years the family became Norwegian citi zens. Goldschmidt entered the university himself, majoring in the earth sciences. He earned his Ph.D. in 1911 with a the sis in which he applied the phase rule— recently popularized by Roozeboom [854]—to the mineralogical changes that took place in the earth’s crust. Goldschmidt spent years studying the minerals of Norway, then in 1929 took a post at the University of Gottingen. By working out the chemical consequences of the properties of the elements and by making use of new knowledge of atomic and ionic sizes, Goldschmidt was able to predict in what sort of minerals which elements ought to appear so that miner alogy was no longer a purely descriptive science. Goldschmidt was pioneering in geochemistry as Beno Gutenberg [1133] was pioneering in geophysics. The stay at Gottingen was cut short by Hitler’s coming to power, however, since Goldschmidt was Jewish. In 1935 he re turned to Norway. Nor did that remain a safe haven, for in 1940 Norway was occupied by Germany and Goldschmidt had to leave for England in 1942, travel ing by way of Sweden. He carried a cap sule of cyanide in his mouth in case there was no other way of evading the Nazis. This was only after periods of imprisonment in concentration camps (from which he managed to escape) had ruined his health. In June 1946 he returned to Oslo, but life was essentially over. He died of can cer within a year. [1124] STERN, Otto (shtehrn [German]; stern [English]) German-American physicist
Zory, Poland), February 17, 1888 Died: Berkeley, California, Au gust 17, 1969 Stern, the son of a prosperous Jewish grain merchant, studied physical chemis try at the University of Breslau and re ceived his doctorate in 1912. He spent two years thereafter working for Einstein [1064] before striking out for himself. His first professorial appointment came in 1914 at the University of Frankfurt. He served later at Rostock and at Ham burg.
About 1920 Stern began to work with molecular beams; that is, he allowed gases to escape from a container through a tiny hole into a high vacuum. The es caping molecules met virtually no mole cules with which they could collide in the vacuum, so that they formed a straight beam of moving particles. Al though these molecules (and sometimes he also used metallic atoms) are neutral overall, they are made up of charged particles, a positively charged nucleus and negatively charged electrons. As a result they should behave in some ways like tiny magnets. By studying these beams in a magnetic field through the 1920s and into the early 1930s, Stern was able to confirm that they did act as magnets. He made some measurements of these properties that helped to confirm Planck’s [887] quantum theory. His pupil Rabi [1212] carried matters further. Stem also demonstrated that these mo lecular beams showed wave properties, as De Broglie’s [1157] theories predicted. At the time, Davisson [1078] had al ready proved De Broglie’s theories in the case of electrons, but Stern carried mat ters into the far more massive range of atoms and molecules. In 1933 Stern was compelled to leave Germany when Hitler came to power. In the United States he accepted a post as professor of physics at Carnegie Institute of Technology (now Carnegie-Mellon University) at Pittsburgh, remaining there until his retirement in 1945. In 1943 he was awarded the Nobel Prize in physics for his work on molecular beams. [1125] FRIEDMANN, Alexander Alex androvich (freed'mahn) Russian mathematician Bom: St. Petersburg (now Lenin grad), June 29, 1888 Died: Leningrad, September 16, 1925
Friedmann was the son of a composer, and, on his mother’s side, the grandson 715 [1126] GASSER
WAKSMAN [1128] of a Czech composer. He graduated from St. Petersburg University in 1910. He was interested in meteorology at first and during World War I he was at the front in connection with the Russian air force. He grew interested in Einstein’s [1064] general theory of relativity, and was the first to work out a mathematical analysis of the notion of an expanding universe in 1922, thus removing the “cosmologi cal term,” which Einstein had inserted and later described as the greatest mis take of his life. Friedmann’s model of the universe was the first to make it seem that its beginning would have had to be something like the “big bang” that Lemaitre [1174] and Gamow [1278] would then bring into the mainstream of cosmological thinking. He died of typhoid fever while still in his thirties. [1126] GASSER, Herbert Spencer American physiologist
5, 1888
Died: New York, New York, May 11, 1963 Gasser, the son of an Austrian immi grant who became a physician, was grad uated from the University of Wisconsin in 1910 and he began his medical educa tion at the new medical school being or ganized by the university, taking his physiology course under Erlanger [1023]. He completed his training at Johns Hop kins and obtained his medical degree in 1915.
After the interruption of World War I, during which he served in the Chemical Warfare Service, he joined the faculty of Washington University and worked with Erlanger on nerve potentials, becoming professor of pharmacology in 1921. For this work he shared with Erlanger the 1944 Nobel Prize in medicine and physi ology. In 1931 he was appointed head of the physiology department at Cornell University Medical School and in 1935 he became director of the Rockefeller Institute (now Rockefeller University), retaining that position until his retire ment in 1953. [1127] ZERNICKE, Fritz (tsehrinih-kee) Dutch physicist
March 10, 1966 Zemicke, the son of a headmaster, ob tained his Ph.D. at the University of Amsterdam in 1915 under Kapteyn [815]. He then joined the faculty of the University of Groningen, where he re mained the rest of his life. His great contribution was the devel opment, in 1934, of the phase-contrast microscope. This microscope slightly al ters the phase of diffracted light as com pared with direct light so that the different objects in the cell appear to take on color even though they are col orless in an ordinary microscope. In tracellular objects become clearly visible without staining, and therefore without killing, the cell. After World War II phase-contrast mi croscopes became popular and Zernicke was awarded the 1953 Nobel Prize in physics. [1128] WAKSMAN, Selman Abraham Russian-American microbiologist
1888
Died: Hyannis, Massachusetts, August 16, 1973 Waksman, of Jewish descent, left Rus sia as a high school graduate and arrived in the United States in 1910. He at tended Rutgers University, graduating in 1915, and became an American citizen in 1916. He went to the University of California for further study, obtaining his doctorate there in 1918, then re turned to Rutgers to join the faculty. He was particularly interested in the microorganisms dwelling in the soil, a study that took a sudden new direction in 1939 when Dubos [1235], who had been one of Waksman’s students, discov ered a bacteria-killing agent in a soil microorganism. This helped stimulate a new look at Fleming’s [1077] penicillin, especially since World War II had bro ken out and new methods of handling in-
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