Biographical encyclopedia
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681 [1072] LANGMUIR
STAUDINGER [1074] Langmuir then studied the effect of hot metal surfaces on all sorts of gases. It led him in many directions that had nothing to do with electric lighting, but General Electric had already profited enough from him for a lifetime and they gave him complete freedom to do as he chose. In the mid-1920s, for instance, Lang muir proceeded to develop an atomic hy drogen blowtorch that could produce temperatures almost as hot as the surface of the sun. He did this by allowing a stream of hydrogen to be blown past hot tungsten wires (the connection with his incandescent bulb work is obvious). Under those conditions the hydrogen molecule is broken into its constituent atoms. As the jet of gas leaves the tung sten filament, the hydrogen atoms re combine to form hydrogen molecules, and the heat of this combination produc ing temperatures near 6000°C. His interest in the vacuums within the old electric light bulbs led him to devise methods of producing high-vacuum tubes, which proved essential to radio broadcasting. He also invented a high- vacuum mercury pump. His work on the gas films that formed on metal wires led him to consider how atoms formed bonds with each other. With the independent work of G. N. Lewis [1037], this was the beginning of the modem theory of electronic bonds, in which the dashes of Kekulé [680] are replaced by paired dots, signifying elec trons. He also devised a theory of catal ysis based on the formation of gas films on platinum wires. He found that certain substances will form films on water that are one mole cule thick and was the first to study such monomolecular films. This led to methods of cutting down glare on glass surfaces, for instance. For his work in surface chemistry, Langmuir received the 1932 Nobel Prize in chemistry, the first American industrial scientist to do so. In later life, the most startling contri bution to come out of his laboratories was his work with Schaefer [1309] and Vonnegut [1391] on “rainmaking.” This is the first (if, as yet, only very shakily successful) attempt on the part of man to do more about the weather than just talk. [1073] HESS, Walter Rudolf Swiss physiologist Born: Frauenfeld, Thurgau, March 17, 1881 Died: Zürich, August 12, 1973 Hess was originally an ophthalmol ogist, but he grew interested in physiol ogy, studied it at the University of Bonn, and in 1917 was appointed professor of physiology at the University of Zürich. In order to study in detail the au tonomic nervous system, that portion of the system that controls the various auto matic functions of the human body, he used fine electrodes to destroy tiny, specific sections of the brain of cats and dogs. In this manner, he located the au tonomic centers in the hypothalamus and medulla oblongata so exactly that by stimulating the proper portion of the brain of a cat he could make it behave as it would on the sudden sight of a threatening dog—with no dog in sight. For the deeper understanding of the brain’s functioning that this led to, Hess shared the 1949 Nobel Prize for physiol ogy or medicine with Egas Moniz [1032].
[1074] STALOINGER, Hermann (shtow'ding-er) German chemist
1881
Died: Freiburg-im-Breisgau, Sep tember 8, 1965 Staudinger, the son of a professor, ob tained his doctorate at the University of Halle in 1903. He taught at the Techni cal Institute of Karlsruhe, where he was associated with Haber [977] until 1912. Most of his professional life was spent at the University of Freiburg, where after 1951 he was professor emeritus. He did work in many branches of organic chemistry, but his outstanding labors were on the nature of polymers.
[1075] KARMAN
FISCHER [1076] These are made up of large molecules, which are in turn built up out of a series of small units, something like beads on a string. Starch and cellulose are natural polymers built up out of glucose mole cules from which water has been sub tracted; while proteins are built up out of amino acids from which water has been subtracted. Staudinger showed, in work beginning in 1926, that the various plastics being produced were similar polymers with the simple units being ar ranged in a straight line and that they weren’t, as many had suspected, merely disorderly conglomerates of small mole cules. The consequences of such studies were important enough, in the light of the vast proliferation of plastics after World War II, to earn for Staudinger the 1953 Nobel Prize in chemistry, two years after his retirement. [1075] KARMAN, Theodore von (kahr'mahn) Hungarian-American physicist Born: Budapest, Hungary, May 11, 1881 Died: Aachen, Germany, May 7, 1963
Karman was the son of a professor of education who had been knighted by Emperor Francis Joseph I of Austria- Hungary for his reorganization of Hun garian education. Among Karman’s an cestors was Rabbi Judah Low of Prague who, in legend, had devised the famous automaton called the Golem. Karman was educated at the Royal Polytechnic University in Budapest after his father had deliberately guided him toward engineering, distrusting the youngster’s great proficiency in pure mathematics. He served on the faculty of the university for some years, then went to Gottingen for his postdoctorate work and then to the University of Paris. In Paris in 1908 he saw the flight of one of the early airplanes and grew interested in aeronautical engineering, something that occupied him the rest of his life. He analyzed fluids in motion, and turbu lence, and established the theory of aeronautics that, until then, had been in the hands of trial-and-error engineers. Karman and his student laid the groundwork for the designs that lead to supersonic flight. This was while he was in the United States, to which he had been invited in 1930 and where he de cided to stay as the advance of Nazism was casting its shadow over Germany. He taught at California Institute of Technology and was largely responsible for its emergence as a top aeronautical research center. He became an American citizen in 1936. [1076] FISCHER, Hans German chemist
of Frankfurt), July 27, 1881 Died: Munich, Bavaria, March 31, 1945 Fischer, the son of a dye chemist, ob tained his doctorate in chemistry in 1904 at the University of Marburg and then took up medicine, obtaining his M.D. at the University of Munich in 1908. Trained in both disciplines, he became assistant to Emil Fischer [833] (no rela tion) at the University of Berlin. In 1916 he received his first professorial appoint ment, at the University of Innsbruck, succeeding Windaus [1046], who had moved on to Gottingen. However, it was only in 1921, when Fischer accepted a position at the Uni versity of Munich, that his research re ally began to move. He got to work on the chemical structure of heme, that por tion of hemoglobin (the red coloring matter of blood) not amino acid in na ture. Painstakingly he and the students working under him took it apart into simpler components and discovered that it was made up of four pyrrole rings (consisting of four carbon atoms and a nitrogen atom each) arranged in a larger ring. Little by little the finer points were straightened out and by 1929 he had lo cated every last atom in the heme mole cule. From the standpoint of pure virtu osity, it was an extraordinary example of solving an organic jigsaw puzzle by care ful work and reasoning, one not to be 683 [1077] FLEMING
FLEMING [1077] outdone until Sanger [1426] and his group took on the structure of insulin a generation later. For this work Fischer was awarded the 1930 Nobel Prize in chemistry. He went on to tackle chlorophyll, the green coloring matter of plants, on which Willstatter [1009] had expended so much effort. Chlorophyll has a molec ular constitution quite like that of heme but there were subtle differences that were not easy to track down. Fischer devoted the 1930s to the task and even tually succeeded, working out the com plete structure of the chlorophyll mole cule. The red of blood and the green of leaves had both given up their secrets to him. He remained in Germany during World War II and died a month before his country’s defeat, committing suicide in despair after mass air raids on Mu nich had destroyed his laboratory. [1077] FLEMING, Sir Alexander Scottish bacteriologist Born: Lochfield, Aryshire, August 6, 1881
Died: London, England, March 11, 1955 Fleming, the seventh of eight children of a farmer, was educated at Kilmarnock Academy, but after graduation, the fact that his father had died while he was young and that his family was poor, forced him to go to work in London as a shipping clerk. In 1900 he joined the army, but he was too late to see service in the Boer War. In 1902 he earned a scholarship and that, combined with a legacy from an uncle, allowed him to begin medical studies at the University of London. He made a brilliant mark as a medical student and took his degree in 1906. In World War I he served in the Brit ish army’s medical corps, ending with the rank of captain. When the war was over, he obtained a professorial position at the Royal College of Surgeons in 1919. From the start he was interested in bacteriology, particularly the chemother apy of disease. He pioneered the intro duction of Ehrlich’s [845] Salvarsan in Great Britain. During the war he had begun a line of research that culminated in 1922 in the discovery of a protein called lysozyme. This is found in tears and mucus and has bacteria-killing properties. (The art of bacteria-killing led into other interesting byways. Twort [1055], during those same years, uncovered a special sort of parasite that was quite deadly to bacte ria.)
Fleming’s chief discovery, however, came by accident. In 1928, when he was appointed professor of bacteriology at the school where he had been a medical student, he left a culture of staphylo coccus germs uncovered for some days. He was through with it and was about to discard the dish containing the culture when he noticed that some specks of mold had fallen into it. That in itself was nothing, but about every speck the bac terial colony had dissolved away for a short distance. Bacteria had died and no new growth had invaded the area. (Tyn dall [626] had briefly noted a similar ob servation a half century earlier.) Fleming isolated the mold and eventu ally identified it as one called Penicillium notatum, closely related to the common variety often found growing on stale bread. Fleming decided that the mold liberated some compound that, at the very least, inhibited bacterial growth. He called the substance, whatever it was, penicillin. He cultured the mold and attempted to grow various types of bacteria in its neighborhood. Some grew well; others would not approach the mold past a cer tain distance. Apparently penicillin affected some germs and not others. Fleming further experimented on the effect of the chemical on white blood cells. It was, after all, no trick to find something that was poisonous to bacte ria. If it was also poisonous to human cells, nothing was gained. However, pen icillin did not affect the white blood cells at all at concentrations that were highly deleterious to bacteria. Unfortunately Fleming came to the
[1078] DAVISSON
BARKHAUSEN [1079] end of his rope. He was no chemist and could not isolate or identify the sub stance; nor did he arouse much interest in the descriptions he published of these unusual results. The coming of World War II altered matters. The discovery of new antibac terials would be of the highest impor tance in the treatment of wounded sol diers and Florey [1213] and Chain [1306] set to work isolating penicillin. They succeeded, and it proved to be as successful as Fleming’s first experiments had shown it would be. Penicillin was the first important example of what Waksman [1128] was soon to call the antibiotics. However, the delay between Fleming’s experiments and their fulfillment allowed the development of the sulfa drugs through the work of Domagk [1183], and it was the sulfa drugs (not, strictly speaking, antibiotics) that initiated the age of the wonder drugs. With the value of penicillin proved to the hilt, Fleming was knighted in 1944 and, along with Florey and Chain, awarded the 1945 Nobel Prize in medi cine and physiology. [1078] DAVISSON, Clinton Joseph American physicist Born: Bloomington, Illinois, Oc tober 22, 1881 Died: Charlottesville, Virginia, February 1, 1958 Davisson, the son of a paperhanger, entered the University of Chicago on a scholarship in 1902 and attracted the favorable attention of Millikan [969]. With Millikan’s recommendation he en tered Princeton for graduate work in physics and obtained his doctorate in 1911, working under the supervision of Richardson [1066] on the emission of ions by heated materials. After he had obtained his degree, he married Richard son’s sister. Davisson worked at the Carnegie Insti tute of Technology (now Camegie- Mellon University) in Pittsburgh from 1911 to 1917, except that he spent the summer of 1913 in England working with J. J. Thomson [869]. When the United States entered World War I, he obtained leave of absence to join the company now known as the American Telephone and Telegraph Company (the Bell System) and remained there. (He tried to enlist, but was turned down for reasons of health.) Davisson was interested in De Bro glie’s [1157] theory of the wave nature of electrons, first announced in 1924, but Davisson probably never suspected that he was going to demonstrate that wave nature experimentally. He did it by acci dent.
In 1925 he was studying the reflection of electrons from a metallic nickel target enclosed in a vacuum tube. The tube shattered by accident and the heated nickel promptly developed a film of oxide that made it useless as a target. To remove the film, he had to heat the nickel for an extended period. Once this was done, he found that the reflecting properties of the nickel had changed. Investigation showed that whereas the target had contained many tiny crystal surfaces before heating, it contained just a few large crystal surfaces afterward. Davisson followed this out to its logical conclusion and prepared a single nickel crystal for use as a target. Now he found that the electron beam was more than reflected. It was diffracted as well. But diffraction is characteristic of waves, not particles, and in this manner the wave nature of electrons was proved and De Broglie’s theory was confirmed. Addi tional confirmation was received that same year by the independent and different work of G. P. Thomson [1156]. As a result Davisson and Thomson shared the 1937 Nobel Prize in physics. [1079] BARKHAUSEN, Heinrich (bahrk'how-zen) German physicist
Barkhausen, the son of a judge, ob tained his Ph.D. in 1907 and in 1911 be-
[1080] BRIDGMAN
FRANCK [1081] came professor of communications en gineering at the University of Dresden. Barkhausen’s main contribution to physics arose over the magnetization of iron. As iron is subjected to a con tinuously increasing magnetic field, its magnetization increases by little jerks rather than smoothly. These jerks are ac tually accompanied by noise, which can be heard as a series of clicks when magnified through a loudspeaker. This Barkhausen effect was explained eventually when it came to be realized that iron consists of a series of minute domains within which all the tiny atomic magnets are lined up. Separate domains are strong magnets but each is canceled by the next, so that ordinary iron is not magnetized. As the domains are sub jected to a strong magnetic field, how ever, they all line up and the iron, gener ally, becomes a magnet. As the domains line up, one rubs against its neighbor and the vibrations thus set up account for the noise.
This arrangement by domains is char acteristic of ferromagnetic substances, that is, those substances capable of form ing strong magnets—of which iron is chief. [1080] BRIDGMAN, Percy Williams American physicist Born: Cambridge, Massachusetts, April 21, 1882 Died: Randolph, New Hampshire, August 20, 1961 Bridgman, the son of a newspaper re porter, had his scientific life entirely bound up with Harvard. After an educa tion in the public schools of Newton, Massachusetts, he entered Harvard in 1900, earning successive degrees there up to his Ph.D. in 1908. Immediately after obtaining his doctorate he joined the faculty, attaining a professorial posi tion in 1913 and remaining until his re tirement in 1954. Even as a candidate for the doctor’s degree, Bridgman was already working in the field of high pressures. In 1905 the equipment with which he was work ing failed under the pressures he wanted to use and he turned his attention to the design of equipment that would not fail. In the early apparatus it had been the seals at the joints that had given. Bridg man therefore designed seals that squeezed tighter together as the pressure increased so that only the strength of the material making up the chamber was the limit of permissible pressure. Quite early in the game he reached a pressure of 20,000 atmospheres (128 tons to the square inch). By using stronger materials and by putting pressure on his container from the outside, he. kept reaching higher and higher pressures up to 400,000 atmo spheres. Through use of these higher pressures, he was able to study new forms of solids. This was valuable not only in itself, but also for the light it threw on substances and processes deep within the earth. A dramatic conse quence was announced in 1955 when, with Bridgman as a consultant, research workers at General Electric were able finally to form synthetic diamonds by the use of a combination of high pressure and high temperature. For his work Bridgman had received the 1946 Nobel Prize in physics. Bridgman was a poor lecturer but he was an important philosopher of science, writing thoughtful books on the nature of physics. In 1961, almost eighty years old, with over half a century of success behind him, and incurably and painfully ill, Bridgman shot himself to death, writ ing a note stating it was the last day he would be physically able to do so. He pointed out that it was indecent of soci ety to turn its back and force him to do it without help or sympathy. [1081] FRANCK, James German-American physicist Born: Hamburg, August 26, 1882 Died: Gottingen, May 21, 1964 Franck, the son of a Jewish banker, studied chemistry at the University of Heidelberg, then physics at the Univer sity of Berlin, where he obtained his
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