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446 [680] KEKUI.fi VON STRADONITZ KEKUI.fi VON STRADONITZ
hydrogen sulfide H — S —H, H H
I I alcohol
H — C — C—O — H, I I
H H H H
H1 H■ diethyl
ether 1 H —C i 1 - C — O- 1 1 - C - -C —H, I I H I H iH IH and acetic acid H — C — C—O —H. I H One of the strongest supporters of this way of doing things was Butlerov [676] in Russia. Such structural formulas made sense out of organic compounds (especially since Kekule allowed for double bonds and triple bonds), gave each a precise and individual representation, and ex plained how isomers, such as those first discovered by Liebig and Wohler [515], could exist. Isomers, it could be easily shown, had molecules made up of the same atoms possessing the same valences, but arranged differently. An easy case is H H
that of ethyl alcohol
1 H — C
I 1 - C - O - H , | H H
H H and dimethyl ether 1 H - Cl K 1 -o - 1 0 1 l H H The structural formulas offered guides to chemists interested in synthesizing new compounds, as Perkin [734] had just done. Kekule was famous enough now to be able to initiate the meeting of the First International Chemical Congress at Karlsruhe, where Cannizzaro starred and where the matter of organic molecular structure began to be put in order. In 1861 Kekule published the first vol ume of a textbook of organic chemistry in which he (mindful of the work of Berthelot [674]) was the first to define or ganic chemistry as merely the chemistry of carbon compounds. There was no mention of the living or once-living or ganisms featured in Berzelius’ [425] orig inal definition, another blow to vitalism. There still remained one major prob lem in the field of organic structural chemistry: the structure of benzene (C6H6), a substance which had been discovered in 1825 by Faraday [474] and named by Mitscherlich [485] in 1834. This was most important in connection with the new synthetic dyes that were being built up by Perkin and others. Without a proper idea of its structure, progress could be much impeded. Again it was Kekule to the rescue. He had a feeling for building up atomic structures, perhaps because of his early architectural interests. In any case, one day in 1865 (according to his own ver sion of the story), while in a semidoze on a bus, it seemed to him he saw atoms whirling in a dance. Suddenly the tail end of one chain attached itself to the head end and formed a spinning ring. If he had been Archimedes [47], Kekule might have sprung off the bus and run down the street yelling, “Eureka!” How ever, he was a dignified German scholar and merely published his suggestions in the accepted manner. He introduced the notion of rings of carbon atoms, and benzene came to be represented thus: H I I II
I H or simply: 447 [681] HALL
HALL [681] (On the centenary of this discovery, in 1965, the Belgian Government issued a commemorative stamp.) In 1867 Kekulé moved on to the Uni versity of Bonn, where he spent the re mainder of his life. Kekulé’s structural notions were soon made three-dimensional by Van’t Hoff [829] and Le Bel [787], were elaborated into an electronic theory by Lewis [1037], and further elaborated through quan tum mechanics by Pauling [1236], but the essence of the Kekulé structure remains. It has guided chemists through the maze of synthesis for a century and despite all modifications still serves to depict the organic molecule and to help predict its reactions. The last twenty years of his life, dur ing which he was plagued by ill health and an unhappy second marriage, saw little accomplished. He was ennobled by Emperor William II in 1895 so that he could then add “von Stradonitz” to his name.
[681] HALL, Asaph American astronomer Born: Goshen, Connecticut, Oc tober 15, 1829 Died: Goshen, Connecticut, No vember 22, 1907 Asaph Hall had a hard start. His fa ther, an unsuccessful clock salesman, died when he was thirteen and Asaph had to leave school to support his family as apprentice to a carpenter. After that he was largely self-taught, picking up education wherever he could, a bit here and a bit there. He married Angelina Stickney, under whom he had studied mathematics and, with her full support, made up his mind to become an astronomer. In 1857, he managed to become an assistant to G. P. Bond [660] at Harvard College Observa tory. His salary was three dollars a week. After a year it was raised to eight dollars a week. In 1863 Hall had proved his worth to the point where he was appointed profes sor of astronomy at the United States Naval Observatory in Washington. While there in 1876 he discovered a white spot on Saturn’s surface and used it to show Saturn’s period of rotation to be 10% hours. In 1877 he made his most dramatic discovery. At the time, eighteen satellites were known to exist in the solar system, four of Jupiter, eight of Saturn, four of Uranus, and one of Neptune. This makes seventeen, but of course the eigh teenth is our own moon. No satellites were known for Mercury, Venus, or Mars and if those three planets had any they must be very small. Mercury and Venus were hard to inspect for tiny sat ellites because they were so often close to the sun. Mars, however, was another matter. In 1877 Mars was approaching a fa vorable conjunction and would be only some thirty-five million miles from the earth. All telescopes were turning to it and Hall had at his disposal a 26-inch refractor, then the largest in the world. (It was during this conjunction that Schiaparelli [714] was to start the fa mous Martian canal controversy.) Hall began to search the neighborhood of Mars for small satellites at the begin ning of August. He worked his way sys tematically inward toward Mars’s sur face. By August 11 he was so close to Mars that its glare was beginning to interfere with his observations. He de cided to give up, went home, and told his wife of his decision. Mrs. Hall said, ‘Try it just one more night.” Hall agreed to do so and on that one more night discovered a tiny, moving ob ject near Mars. Unfortunately clouds came in and he had to wait for five agonizingly suspenseful days for another chance to look. On August 16 he could see and definitely observed a satellite. On the seventeenth he found another. They were small satellites, the larger some fifteen miles in diameter, the smaller seven and a half. What’s more they were very close to Mars. The inner satellite revolved about Mars faster than Mars rotated on its axis, so that from the Martian surface it would seem to rise in the west and set in the east. Hall named the satellites Phobos (“fear”) and
[682] THOMSON
MAREY [683] Deimos (“terror”) after the two sons of the war-god Ares in the Greek myth. In 1892 Mrs. Hall died, and in 1898 Hall moved to Harvard as a professor of astronomy, retiring to his home town in 1903. One sad touch to Hall’s great discov ery, by the way, was the fact that Newcomb [713], who was Hall’s supe rior at the time, took an unfair share of the press coverage that followed. How ever, he eventually apologized to the offended Hall for this, and the final touch came when rocket probes mapped the surface of the two satellites, for then the two largest craters on Phobos were named Hall and Stickney as a well- earned tribute to the professor and his wife.
[682] THOMSON, Sir Charles Wyville Scottish zoologist Born: Bonsyde, West Lothian, March 5, 1830 Died: Bonsyde, March 10, 1882 Thomson’s name was originally Wy ville Thomas Charles, but he changed it in 1876, when he was knighted, to the form given above. The son of a surgeon, he studied medicine at the University of Edinburgh, but ill health forced him out in 1850 before he could get his degree. He grew interested in natural history and received academic appointments that culminated, in 1870, in a professorship in natural history at the University of Edinburgh. His chief interest came to be the life of the ocean depths. It had always been assumed (by those who thought of it at all) that ocean life was confined to the surface layer and that the depths, with their cold, darkness, and enormous pressures, were bare of life. However, in 1860 when a cable at the bottom of the Mediterranean was dredged up, life forms were found clinging to it though it had lain at the depth of a mile. Thomson undertook deep-sea dredging operations in 1868 and 1869 and found representatives of all the chief groups of animal life at considerable depth. His biggest chance, came with the ex pedition of the corvette Challenger, which in 1872 took off on a four-year combing of the seven seas. Thomson sailed with it as the head of a staff of six naturalists in the tradition of Banks [331] and Darwin [554], everywhere col lecting biological samples from great depths. In the course of the voyage, the
took 372 deep-sea soundings, and intro duced man to the three-dimensional phe nomenon of the ocean. Life was shown, once and for all, to inhabit all the ocean, from top to bot tom. And, as we know now, life is even to be found at the bottom-most foot of the deepest abyss. [683] MAREY, Étienne Jules (muh-rayO French physiologist
5, 1830
Died: Paris, May 15, 1904 Marey obtained his doctor’s degree in 1857 at the Faculty of Medicine of Paris. He was professor at the Collège de France from 1870 to his death. To begin with he was particularly in terested in the mechanism of blood cir culation and in the devising of instru ments to record the pulse rate and the blood pressure. He invented the first sphygmograph for the purpose in 1863, and his instrument continued, in princi ple, to be used into our own time. Marey then became interested in ani mal locomotion, in the details of just how a horse moved its legs in order to walk, run, trot, or canter; and in just how a bird moved its wings in order to fly. He realized that this could best be determined by taking photographs of a moving animal in rapid succession. Beginning in 1881 he devoted himself to animal photography. He succeeded in modifying cameras so as to produce pho tographs spaced so closely together that by viewing them in rapid succession, the illusion of motion could be obtained. Not only did Marey, in this way, ratio nalize animal motion so that old paintings of galloping horses shown with two forelegs extended forward and two
[684] RAOULT
COUPER [686] hindlegs extended backward as in a rock ing horse were seen to be completely wrong, but he was also an important forerunner of the invention of motion pictures. [684] RAOULT, François Marie (rah- ooO
French physical chemist Born: Fournes-en-Weppes, Nord, May 10, 1830 Died: Grenoble, Isère, April 1, 1901
Raoult, after considerable difficulties because of poverty, obtained his doctor’s degree at the University of Paris in 1863 and after a stay at the University of Sens joined the faculty of the University of Grenoble, obtaining a professorial posi tion there in 1870. He was one of the founders of physical chemistry along with Van’t Hoff [829], Ostwald [840], and Arrhenius [894]. His studies of solutions led him in 1886 to propound what is now known as Raoult’s law: the partial pressure of solvent vapor in equilibrium with a solu tion is directly proportional to the ratio of the number of solvent molecules to solute molecules. This led to a method for calculating molecular weights of dis solved substances and could also be used to show that the freezing point was de pressed (and the boiling point elevated) in proportion to the number of particles of solute present in the solution. It was the anomalous behavior of elec trolytes in this respect that led Arrhenius to work out his theory of electrolytic dis sociation. [685] MEYER, Julius Lothar German chemist
19, 1830 Died: Tübingen, Württemberg, April 11, 1895 Meyer, the son of a physician, was troubled by illness and headaches even as a youth. He earned his degree as a physician in 1854 at the University of Wurzburg, where he attended the lec tures by Virchow [632] and obtained his Ph.D. at the University of Breslau in 1858. He began studying the nature and function of blood, but, nearly from the start, chemistry was his main interest. He studied under Bunsen [565] and Kirchhoff [648]. In 1864 he wrote a text on chemistry and in the course of it con sidered how the behavior of the elements might depend on their atomic weights. In this respect he, like Mendeleev [705], had been influenced by Cannizzaro’s [668] remarks at the Karlsruhe Congress. Meyer concentrated on the atomic vol ume (the room taken up by atoms of the individual elements). He found that if he plotted the atomic volume against the molecular weight, the line drawn through the plotted points rose and fell first in two short periods, then in two long periods. This was exactly what Mendeleev had discovered in connection with valence, but whereas Mendeleev published in 1869, Meyer did not publish until 1870. Furthermore, Meyer, as he himself was later ruefully to admit, lacked the courage to predict the existence of undis covered elements. Nevertheless, Meyer is often given part credit for the discovery of the periodic table. In 1882, for in stance, he and Mendeleev received the Davy medal of the Royal Society, jointly. Meyer served as an army surgeon dur ing the Franco-Prussian War. [686] COUPER, Archibald Scott (koo'per) Scottish chemist Born: Kirkintilloch, Dumbarton shire, March 31, 1831 Died: Kirkintilloch, March 11, 1892
After a childhood in delicate health, during which most of his education was at home, Couper, the son of a mill owner, entered the University of Edin burgh in 1852. There he studied under Hamilton [545], then went on to Berlin 450 [687] SUESS
DEDEKIND [688] and Paris in 1856. In the latter city he studied under Wurtz [602]. He is known for a single paper, pub lished in 1858 under the sponsorship of Dumas [514], in which he paralleled some of Kekule’s [680] thinking and suggested the dash or a dotted line to represent the chemical bond, which Er- lenmeyer [661] went on to popularize. As a result of some delay that was the fault of Wurtz, Couper published two months after Kekule and there was some controversy over priority as a conse quence. Shortly afterward Couper suffered a nervous breakdown, perhaps as a result of the strain of the contro versy. Then came sunstroke, and his scientific career was over before he was thirty, though he lived on for thirty years more. [687] SUESS, Eduard (zyoos) Austrian geologist
20, 1831 Died: Marz, Burgenland, April 26, 1914
Suess was the son of an Austrian who was running a wool business in London at the time the child was born. When Suess was three, the family returned to Austria. Suess was educated in Vienna and in Prague and was on the side of the lib erals during the revolutionary distur bances in 1848, though he missed the worst of them when he stayed with his grandparents in Prague. Nevertheless, he did undergo a short period of imprison ment at the end of 1850. He grew interested in geology and paleontology. His father, suspecting he would not be able to support himself, en deavored to make Suess work in a leather factory, but a professorial ap pointment at the University of Vienna (even though he lacked a doctor’s de gree) saved him from that fate. Suess’s interest in geology led him to advocate the bringing of drinking water into Vienna from mountain springs in stead of using disease-laden wells. The aqueduct began operation in 1873. He also supervised the production of the Danube canal, which was opened in 1876 and which put an end to the flood ing of the low-lying sections of Vienna. Suess did not feel that mountains were formed by the uplifting of the crust, but by thrusting movements that crumpled the crust, and in this he appears to have been right. He also traced the advance and retreat of the coastline, being the first to attempt to describe the panorama of the changing continents through the geologic ages. Here he was plagued by the lack of knowledge of the sea bottom. His ideas were replaced by those of Wegener [1071], Ewing [1303] and others, a half-century and more later. Beginning in 1873, he spent thirty years as a Liberal in the Austrian legisla ture.
[688] DEDEKIND, Julius Wilhelm Rich ard (day'deh-kint) German mathematician
wick), October 6, 1831 Died: Braunschweig, February 12, 1916
Dedekind, the son of a lawyer, began his college career in the physical sciences but drifted to mathematics and obtained his Ph.D. in 1852 under Gauss [415]. He was Gauss’s last student and he was a close friend of Riemann [670]. In 1854 he began to lecture in Gottingen and was the first to introduce Galois’s [571] work into the mathematical mainstream. His best-known work involves the irra tionals, first discovered by Pythagoras [7] and his followers and a thorn in the side of mathematicians ever since—to the point where men such as Kronecker [645] wanted to do away with them alto gether. Dedekind instead tried to present a logical picture of the irrationals by in troducing “cuts.” One can picture this by imagining the number series as repre senting the points on a line. The line may be cut in a certain fashion and by careful mathematical reasoning one can show that the cut may be at a rational number or at an irrational, but that the same rules of manipulation will be valid
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