Biographical encyclopedia
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[319] GUYTON DE MORVEAU, Baron Louis Bernard (gee-ton' duh mawr-voh') French chemist Born: Dijon, Côte d’Or, January 4, 1737
Died: Paris, January 2, 1816 Guyton de Morveau, the son of a law yer, was himself a lawyer by profession and served in the Dijon parliament be fore the French Revolution. Science was his hobby and, in 1782, when he retired from his legal position, he turned to chemistry. Already, in 1772, he had as an ama teur demonstrated by careful weighing that rusted metals were indeed heavier than the metals themselves as earlier chemists had maintained on the basis of cruder observations all the way back to Boyle [212]. This fit Lavoisier’s [334] new chemistry when that was developed. His problems with chemical nomencla ture led to a fruitful collaboration with Lavoisier. With the revolution in full swing, he turned to politics again, on the side of the revolutionists, and lived
[320] GALVANI
HERSCHEL [321] through the period—which is more than Lavoisier did. Sadly enough, Guyton de Morveau was another of Lavoisier’s as sociates who, like Fourcroy [366], made no move to save the great man. Guyton de Morveau suggested to the French revolutionaries that balloons be used for military reconnaissance and so he may be considered the great-grand father of aerial warfare. He served as master of the mint under Napoleon, and in 1811 he was made a baron. [320] GALVANI, Luigi (gahl-vah'nee) Italian anatomist
Galvani studied theology in early life but turned to medicine and received his medical degree in 1759 from the Univer sity of Bologna. In 1762, he began lec turing on medicine there and in 1775 he became professor of anatomy. It was his good fortune that electrical machines, such as Leyden jars, were the scientific rage of the time. They could be found in most laboratories, including the one in which Galvani carried on his anatomical and physiological researches. Galvani noticed, in 1771, that the muscles of dissected frog legs (some say they were in the laboratory because they were about to be used in the preparation of soup) twitched wildly when a spark from an electric machine struck them, or when a metal scalpel touched them while such a machine was in operation, even though the spark made no direct contact. This was, in itself, not too surprising. Electric shocks made living muscles twitch, why not dead ones too? Since Franklin [272] had shown light ning to be electrical in nature a genera tion before, the frog muscles might be expected to twitch during a thunder storm. This would be independent confirmation of the electrical nature of lightning. Galvani therefore laid frog muscles out on brass hooks outside the window so that they rested against an iron latticework. The muscles did indeed twitch during the thunderstorm, but they also twitched in the absence of it. In fact, they twitched whenever they made contact with two different metals. Apparently electricity was involved, but where did it come from—the metals or the muscle? Being an anatomist he had a natural predilection toward living tissue, and he decided on the muscle. He declared there was such a thing as ani mal electricity and clung to that view fiercely. He was proved wrong some years later by Volta [337] and ended his life in disappointment. Even his univer sity appointment was lost, for in 1797 he refused to swear allegiance to a new gov ernment set up in northern Italy by the young French general, Napoleon Bona parte—so that he died in poverty, too. In the last decade of his life, however, Galvani had succeeded in making his name a household word. The steady electricity set up by two metals in con tact was called galvanic electricity, as op posed to the static electricity set up by rubbing amber or glass. A person stung into sudden action by an electric current (or by any attack of strong emotion) is galvanized. Iron on which crystals of zinc are layered by means of an electric current (or even, eventually, by means other than an electric current) is said to be galvanized iron. Finally an instrument designed to detect electric current was invented in 1820 and, at the suggestion of Ampère [407], was named a gal vanometer. [321] HERSCHEL, Sir William German-English astronomer
vember 15, 1738 Died: Slough, Buckinghamshire, England, August 25, 1822 At the time of Herschel’s birth, Han nover was a possession of King George II of England (though it was not actu ally part of the British realm). Her- schel’s father was a musician in the Han noverian army and Herschel himself was headed toward the same profession. The coming of the Seven Years’ War, how ever, and the occupation of Hannover by the French made army life somewhat 212 [321] HERSCHEL
HERSCHEL [321] unattractive, and Herschel’s parents managed in 1757 to spirit him out of the service and smuggle him into England. Herschel stayed in England for the rest of his life and adapted himself thor oughly to his new home, changing his German name of Friedrich Wilhelm to the English “William.” His musical tal ents brought him success in England. He arrived in Leeds in 1757 and by 1766 he was a well-known organist and music teacher at the resort city of Bath, tutoring up to thirty-five pupils a week. Economic security gave him a chance to gratify his fervent desire for learning. He taught himself Latin and Italian. The theory of musical sounds led him to mathematics and that to optics. Optics led him to a book about Newton’s work and suddenly he was filled with a desire to see the heavens for himself. Since he could not afford to buy good telescopes, he decided to grind lenses and make his own instruments for viewing the heavens. He tried two hundred times be fore he made one that satisfied him. In 1772 he returned to Hannover long enough to collect his sister Caroline [352] and take her to England. This proved an exceedingly fortunate move, for Caroline proved as fanatic a lens grinder and amateur astronomer as Herschel himself, and it is not likely that Herschel could have accomplished as much without the heroically single minded help of his sister. (She became the first important woman astronomer.) Together the Herschels ground excel lent lenses. Caroline read aloud to Wil liam and fed him meals a bit at a time, while he ground for hours. They ended with the best telescopes then in exis tence.
Herschel made up his mind to look in systematic fashion at everything in the sky. By 1774 he had not only made him self the best reflector in the world but the first that was actually more efficient than any refractor then existing, so he certainly had the tool for the job. He began to bombard the scientific world with papers describing his observations of the mountains of the moon, on vari able stars, on the possibility that changes in sunspot activity might affect agricul ture on earth, and so on. In 1781, while systematically moving from star to star with his excellent tele scope, Herschel came across an object that appeared as a disc instead of a mere point of light. He made the natural as sumption that he had discovered a new comet and reported it as such. However, additional observations showed that the disc had a sharp edge like a planet and not fuzzy boundaries like a comet. Fur thermore, when enough observations had been made to calculate an orbit, he and others, notably Laplace [347], found that orbit to be nearly circular, like a planet’s, rather than elongated, as a com et’s would be. And to top it off, the orbit of the object lay far outside that of Saturn. The conclusion Herschel came to, with great wonder and delight, was that he had discovered a new planet and had doubled the extent of the known solar system. It was the first new planet to be discovered in historic times. Actually the planet is just barely visi ble to the naked eye and it had been ob served a number of times earlier. It was even included in the star map prepared by Flamsteed [234], who noted it a cen tury earlier in the constellation Taurus and recorded it as 34 Tauri. In 1764 it had been spotted near Venus and it was reported as a satellite of that planet. However, it was Herschel’s telescope that showed the disc and Herschel that finally recognized the object as a planet. Herschel tried to name the planet Georgium Sidus (“George’s Star”) after George III, then king of England. Some astronomers, at the suggestion of Lalande [309], named it Herschel in his honor. In the end, it was decided to stick to mythological names for planets. Bode [344] had suggested the new planet be named Uranus after the father of Saturn (in Greek “Cronos”) and by the mid nineteenth century this was universally accepted. The news of the discovery of Uranus made a tremendous sensation. Astrono mers had thought that Newton [231] left them nothing to discover, and Frederick II of Prussia (no scientist, to be sure, 213 [321] HERSCHEL
HERSCHEL [321] though a patron of scientists) believed all scientific findings had already been made. Herschel’s announcement was like a breath of fresh air, indicating that there yet remained portions of the un known. (The same false complacency and sharp awakening was to take place a century later in Michelson’s [835] time.) Herschel was elected to membership in the Royal Society in 1781 and awarded the Copley prize. George III, who was of Hannoverian extraction and who was pleased with the achievement of a fellow countryman, pardoned Herschel’s youth ful desertion from the Hannoverian army and appointed him his private as tronomer at a salary of three hundred guineas a year. Herschel started astronomical observa tions in earnest. For a while he had to continue to manufacture and sell tele scopes (the king’s subsidy was not much), but in 1788 he married a wealthy widow and became a full-time observer. (Caroline remained unmarried and continued to devote herself to her now-famous brother and to astronomy.) Herschel became the most important and successful astronomer of his time. No one else could have been mentioned in the same breath. Like Bradley [258], Herschel tried to observe the parallax of stars and failed. However, he used a method first suggested by Galileo [166], which was to concentrate on pairs of stars in close proximity (such pairs hav ing first been discovered by Riccioli [185] nearly a century and a half be fore). At the time it was thought that these stars were close together only through the accident of happening to lie in nearly the same line of sight, and that one might, in actuality, be very many times farther away than the other. If that were so, the nearer star ought to show a parallactic shift in position in compari son with the farther one. This is undoubtedly the situation on occasion, but in a number of cases that Herschel tried, he found that neither showed a parallactic shift in position. They moved, but from the manner in which they were moving he could only conclude that they were close to each other not only in appearance, but also in actuality. By 1793 he was convinced that they were circling each other. In the course of his career he discovered some eight hundred such double stars or “bi nary stars,” as he called them. This was the first indication that dou ble stars might really be just that. Fur thermore, by studying them it was possi ble to show that their motions were in accord with Newton’s law of gravity. Until then the validity of the law could only be tested within the solar system. Now, a century after the establishment of the law, it was traced out in the mo tions of incredibly distant stars and the theory first truly earned its title of Uni versal. Herschel was as thorough in ob serving stars whose luminosity varied and was the first systematic reporter on variable stars. In 1801, during a short lull in the Napoleonic Wars, Herschel visited Paris and met Laplace and Napoleon himself. Herschel was unimpressed with Napo leon, detecting the latter’s way of affect ing to know more than he really did know. Herschel’s voluminous observations of the stars gave him an overall view of the starry universe that no predecessor had had. In fact, Herschel was the first to present an astronomical picture in which the solar system was reduced to what, in point of fact, it really was, a tiny and in considerable speck in the vast universe of the stars. For instance, in analyzing the proper motions of a large number of stars, he believed, by 1805, that he could explain the regularities he observed by assuming that the sun itself was moving toward a point in the constellation Her cules, a matter studied more thoroughly by Argelander [508]. Just as Copernicus [127] had dethroned the earth as the mo tionless center of the universe, so Her schel dethroned the sun. By studying the Milky Way and count ing stars in various directions, Herschel prepared a picture of the starry system as a whole. He viewed the visible uni verse as representing a gigantic collection of stars arranged roughly in the shape of a grindstone. Our own sun, he believed, was located somewhere near the center of the system and when we looked out in
[321] HERSCHEL
SAUSSURE [322] the directions of the long axis of the grindstone, we saw a vast multiplicity of stars that faded (through distance) into the general faint glimmer of the Milky Way. (The sun’s apparent position in the center of this system was to be shown an illusion a century later by Shapley [ 1102
].) Herschel also viewed various cloudy objects in the skies, cataloguing some twenty-five hundred of them. His own better telescopes resolved into stars some of the objects viewed and recorded by Messier [305], so that he discovered the large “galactic cluster,” like the one in Hercules. Other objects remained unre solved, and Herschel speculated that they might be other huge star collections (or “galaxies”) like our own. He also observed dark areas in the Milky Way which we now know to be clouds of dust. Herschel believed they were empty gaps and said, “Surely this is a hole in the heavens.” Nor did he entirely neglect the solar system after his discovery of Uranus. He returned to Uranus with improved tele scopes and in 1787 discovered two of its satellites, Titania and Oberon. (He had become more English than the English and abandoned classic mythology for Shakespeare.) He reported four other satellites, but those proved to be mis takes. He built a brand-new telescope, forty feet long with a 48-inch reflector. George III contributed £4,000 toward its construction and took proprietary delight in showing the instrument to visi tors. On the first night of observation Hershel turned the telescope on Saturn and discovered two new satellites, En- celadus and Mimas, which, added to the one discovered by Huygens [215] and the four by Cassini [209], made a total of seven for the ringed planet. Herschel also timed the period of rotation of Sat urn and showed that its rings rotated as well.
He was not without an occasional pe culiar idea, however. He thought the moon and the planets were inhabited. He also suggested that the luminosity of the sun might be confined to its atmosphere and that under its belt of fire was a cold, solid body that might even be inhabited. The sunspots, he speculated, were holes in the atmosphere through which the cold surface could be seen. No one took this notion seriously except cranks and faddists, who were pleased to use the great name of Herschel to cover their own follies. Herschel also extended man’s view in a direction that had nothing directly to do with astronomy. In 1800 he tested various portions of the sun’s spectrum by thermometer to see if he could find in teresting differences in the amount of heat the different colors delivered. He did, but in a rather unexpected way, for he found that the temperature rise was highest in no color at all, at a spot be yond the red end of the spectrum. He concluded that sunlight contained invisi ble light beyond the red. This is now called infrared radiation. The following year Ritter [413] was to extend the visi ble spectrum in the other direction. Herschel was knighted in 1816 and died in the fullness of years and fame, working almost to the end and making his last observations in 1819 when he was in his eighty-first year. He lived eighty-four years, which is Uranus’ pe riod of revolution about the sun. Her schel left a son, John Herschel [479], who was likewise a renowned astronomer. [322] SAUSSURE, Horace Benedict de (soh-syoori) Swiss physicist Born: Geneva, February 17, 1740 Died: Geneva, January 22, 1799 Saussure was the son of a noted agri cultural scientist. He earned his Ph.D. at the University of Geneva in 1759 and in 1762 he obtained a professorial position there, on the recommendation of Haller [278]. He was an enthusiastic mountaineer and was among those who helped create the mountain-climbing craze that has continued ever since. Certainly, he was the first to climb mountains with the no tion of making scientific observations in the process. For the purpose, he devised an electrometer, the first device used to
[323] MÜLLER
MONTGOLFIER [325] measure electric potential. He also con structed a hygrometer for measuring hu midity, the first to use a human hair for the purpose. His investigations produced useful data in both meteorology and ge ology. (In fact, Saussure was the first to use the word “geology,” in 1779.) In 1787 Saussure climbed Mont Blanc, the highest peak of the Alps, and led the second expedition to do so successfully. His own thoughts of the development of the earth were in line with those that Hutton [297] was just publishing, and, in fact, some of the data Saussure gathered was used by Hutton in his book. [323] MÜLLER, Franz Joseph (myoo'- ler)
Austrian mineralogist Born: Nagyszeben, Transylvania, (now Sibiu, Romania), July 1, 1740
Müller, the son of a treasury official, studied law and philosophy in Vienna, but he attended a school of mines, too, and became most interested in mineral ogy. Emperor Joseph II appointed him chief inspector of mines in Transylvania and, on his retirement in 1818, Emperor Francis I raised him to the nobüity as Baron von Reichenstein. In 1782, while working with a gold ore, he obtained a substance that he de cided was a new element. He sent a specimen to Bergman [315], who died before he could complete his investi gation. Müller then sent a sample to Klaproth [335], who confirmed the finding, gave due credit to Müller, and named the element “tellurium.” [324] FRERE, John (freer) English archaeologist
10, 1740 Died: East Dereham, Norfolk, July 12, 1807 Frere, the son of a landowner, entered Cambridge in 1758 and attained his mas ter’s degree there in 1766. He was a practicing lawyer and was a Member of Parliament in 1799. He was elected a member of the Royal Society in 1771. This was for his anti quarian interests. In 1790 he discovered shaped flints which, he suggested, were tools formed by people who did not have the use of metal, and which, he thought, were very old. What’s more, the site seemed to be the source of a great many such tools. He reported this in 1797, but the mat ter roused no interest since the ortho doxy of the time insisted that humanity (and, indeed, the whole universe) was less than six thousand years old. The clear indication of human tools many times older than this was therefore sim ply ignored. It was not until similar finds were made by Boucher [458] a half cen tury later, that the matter could no longer be set aside. [325] MONTGOLFIER, Joseph Michel (mohn-gohl-fyay') French inventor Born: Vidalon-les-Annonay, Au gust 26, 1740 Died: Balaruc-les-Bains, June 26, 1810
MONTGOLFIER, Jacques Etienne French inventor Born: Vidalon-les-Annonay, Jan uary 6, 1745 Died: Serrieres, August 1, 1799 These brothers were two of the sixteen children of a well-to-do paper manufac turer, a family trade of romantic ante cedents. An ancestor at the time of the Crusades was supposed to have discov ered the process while a prisoner in Damascus and to have brought Tsai Lun’s [63] invention to France. The Montgolfiers were first inspired to aeronautics by observing the manner in which the smoke of fire caught up light objects and sent them flying into the air. (A less romantic story has it that Jo seph, the elder brother, had his mind turned toward ballooning by reading Priestley’s [312] account of his experi ments with various gases.) Hot air seemed clearly lighter than
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