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321 [479] HERSCHEL
CORIOLIS [480] tionship to the primitive prevertebrate creatures. Nowadays the vertebrates are lumped together with all creatures that possess a notochord at some stage in their life cycle and the whole group makes up the phylum Chordata. Baer resisted any suggestion that the development of the embryo followed the line of evolutionary development of the species, a doctrine later made famous by Haeckel [707]. Instead he followed the evolutionary theories of the nature- philosophers and thought that creatures evolved from some primitive archetype, each following its own course of devel opment. Darwin [554] made use of Baer’s discoveries to bolster his own theory of evolution, but Baer in his old age remained adamant against Dar winism. [479] HERSCHEL, Sir John Frederick William English astronomer Born: Slough, Buckinghamshire, March 7, 1792 Died: Collingwood, Hawkhurst, Kent, May 11, 1871 The only son of William Herschel [321], the greatest astronomer of his time, John Herschel, perhaps naturally, moved into other fields at first. During his stay at Cambridge, Her- schel was chiefly interested in mathe matics, finishing first in his class and joining Babbage [481] and Peacock [472] in a successful attempt to revitalize mathematics. Yet mathematics did not serve him as a profession. After graduat ing from Cambridge in 1813, he tried chemistry, then law. It did not work. In 1816, with the encouragement of Wollas ton [388], John turned to his father’s profession at last and became an as tronomer. After his father’s death, Herschel de voted years to the rounding out of the older man’s work, using a telescope he and his father had constructed. He cat alogued the double stars and nebulae ob served by the elder Herschel and discov ered some himself. In 1831 he was knighted. In 1833 Herschel decided to do for the southern hemisphere what his father had done for the northern. He went south in January 1834, and for four years his base of operations was at Cape Colony, South Africa. There he completed the work first begun by Hal ley [238] and published the results in a great treatise in 1847. While at it he was the first to measure the brightness of stars with real precision. He discovered that the Magellanic Clouds were thick clusters of stars, as Galileo [166] had shown the Milky Way itself to be, two and a quarter centuries before. His work at the Cape of Good Hope, by the way, inspired a famous series of hoax articles in the New York Sun to the effect that living beings were detected on the moon. On Herschel’s return to England he was made a baronet by Queen Victoria at her coronation in 1837. Herschel was profoundly interested in the new tech nique of photography as developed by Talbot [511] and was one of the first to attempt to apply it to astronomy. He in troduced the use of sodium thiosulfate (“hypo”) to dissolve silver salts and he first made use of the terms “photo graphic negative” and “photographic positive.” In 1848 he was elected president of the Royal Astronomic Society and in 1850, like Newton [231] before him, he was appointed master of the mint. He was not happy at the job and in 1854 (again like Newton) suffered a nervous breakdown. His old age was spent in writing and his text Outlines of Astronomy, which first appeared in 1849 and which reached its twelfth edition shortly after his death, was enormously successful. He also labored in the humanities, produc ing a verse translation of the Iliad, for instance. He was buried in Westminster Abbey, close to the tomb of Newton. [480] CORIOLIS, Gustave Gaspard de (koh-ryoh-lees') French physicist
[481] BABBAGE
BABBAGE [481] Coriolis, a professor of mechanics at the Ecole Polytechnique was limited in his productivity by chronic ill health. Even so, he left his name indelibly marked in physics. In 1835 he took up the matter of mo tion on a spinning surface, both mathe matically and experimentally. The earth rotates once in twenty-four hours. A point at the surface on the equator must travel 25,000 miles in that time, hence move eastward at about a thousand miles an hour. A point on the surface at the latitude of New York need travel only 19,000 miles during a day, and move eastward at a speed of only some eight hundred miles an hour. Air moving from the equator northward retains its faster velocity and therefore moves eastward in comparison with the more slowly moving surface under it. The same is true of water currents. The forces that seem to push moving air and water eastward when moving away from the equator and westward when moving toward the equator are therefore called Coriolis forces. (The word is given the Anglicized pronun ciation of kawr'ee-oh'lis.) It is these forces that set up the whirling motions of hurricanes and tornadoes. In technol ogy they must be taken into account in artillery fire, satellite launchings, and so on. Coriolis was the first to give the exact modern definitions to kinetic energy and work in a textbook published in 1829. The kinetic energy of an object he defined as half its mass times the square of its velocity, while the work done upon an object is equal to the force upon it multiplied by the distance it is moved against resistance. [481] BABBAGE, Charles English mathematician Born: Teignmouth, Devonshire, December 26, 1792 Died: London, October 18, 1871 Babbage was the son of a banker and inherited money (which he was to spend on his work). He taught himself mathe matics and entered Cambridge in 1810. While still at Cambridge, Babbage along with John Herschel [479] and Pea cock [472] founded the Analytic Society in 1815. This was designed to emphasize the abstract nature of algebra, to bring Continental developments in mathe matics to England and to end the state of suspended animation in which British mathematics had remained since the death of Newton [231] a century before. It succeeded and Babbage was elected to the Royal Society in 1816. British math ematicians could thereafter participate in the radical advances initiated by mathe maticians such as Mobius [471], Loba- chevski [484], and Cantor [772]. In 1830 Babbage wrote a controversial book in which he denounced the Royal Society as having grown moribund (which was true). In it, he also deplored the unfavorable climate for science in England, as compared with that in France, much in the manner that a cen tury and a quarter later some Americans compared science in the United States with that in the Soviet Union. He cited the case of Dalton [389], who had to make a precarious living as a teacher after services that in other nations might have earned him a good pension. He fought desperately to effect the reforms he wanted by campaigning to have a man sympathetic to them put in as presi dent of the Royal Society. He lost, how ever.
Babbage worked on what would now be called “operations research” and ad vocated extreme division of labor in fac tories, something Ford [929] was to show could be made practical. Specifi cally, Babbage showed that the cost of collecting and stamping a letter for vari ous sums in accordance with the dis tance it was to travel cost more in labor, time, and money than would be the case if some small, flat sum were charged in dependent of distance. This seemed to go against “common sense” (so many logical conclusions do), but the British government managed to see the point and in 1840 established a modem post age system. Since then, such systems have spread over the world. Babbage worked out the first reliable actuarial tables (the sort of thing that is 323 [481] BABBAGE
ADDISON [482] now the insurance company’s bread and butter), worked out the first speedom eter, and invented skeleton keys and the locomotive cowcatcher. Babbage invented an ophthalmoscope in 1847 by means of which the retina of the eye could be studied. He gave it to a physician friend for testing, but the friend laid it aside and forgot it. Four years later Helmholtz [631] invented a similar instrument, and it is he who now generally gets the credit for it. But there was a much larger disap pointment for Babbage. Most of his life was spent on a vast failure that seems a success only by hindsight. He was very conscious of the errors that littered tables of logarithms and various astro nomical data and applied himself to the correction of those errors. As early as 1822 he began to speculate on the possi bility of using machinery for purposes of computation. Calculating machines had been built by Pascal [207] and Leibniz [233] but Babbage had in mind some thing far more complicated. Somehow he persuaded the British government to invest large sums in the project (a good mechanical computer would have been infinitely useful in both peace and war, but it is rather surprising that a government—any government —of the nineteenth century could have been made to see this) and began work. Unfortunately by the time he was nearly done, he had evolved a much more intri cate scheme, so that in 1834 he scrapped everything and began over. He conceived of a machine that could be directed to work by means of punched cards, that could store partial answers in order to save them for addi tional operations to be performed upon them later, that could print the results. In short, he thought out many of the basic principles that guide modem com puters, but he had only mechanical de vices with which to put them into action. His machine aroused the interest of Ada Augusta, countess of Lovelace and daughter of Lord Byron. It is her de scription of the machine that has pre served the knowledge of it for posterity. He could get no more help from the government. (It obviously didn’t help that he was markedly eccentric almost to the point of madness in some ways. For instance, he carried on an immoderate campaign against organ-grinders, whom he intensely detested.) Nevertheless he continued, spending most of his life and most of his own resources on the ma chine, which grew ever more compli cated. It is preserved still unfinished in the Science Museum in London. In his later years, with his money gone and the demands of the machine unending, Bab bage and Lady Lovelace tried to work up an infallible system for winning at horse races, but failed, of course. Win ning at the track is far more difficult than designing a computer. A century later Norbert Wiener [1175] worked out the mathematical principles behind such computers and men such as Bush [1139] constructed them with the help of electronic devices far more deli cate, responsive, and rapid than the gears and levers available to Babbage. Babbage is thus the grandfather of the modern computer, and although this was not understood by his contemporaries, Babbage himself was probably aware of it. [482] ADDISON, Thomas English physician Born: Longbenton, Northum berland, April 1793 Died: Bristol, Gloucestershire, June 29, 1860 Addison received his medical degree from the University of Edinburgh in 1815, then went on to practice in Lon don. His work at Guy’s Hospital made it famous as a medical school. He described pernicious anemia in 1849 and in 1855 was the first to give an accurate description of the hormone deficiency disease resulting from the de terioration of the adrenal cortex. The condition is commonly called Addison’s disease to this day. Addison’s disease was the first case in which a disease was shown to be as sociated with pathological changes in one of the endocrine glands. 324 [483] STRUVE
LOBACHEVSKI [484] [483] STRUVE, Friedrich Georg Wil helm von (shtroo'vuh) German-Russian astronomer Born: Altona, Schleswig-Holstein, April 15, 1793 Died: Pulkovo, near St. Peters burg (now Leningrad), Russia, November 23, 1864 In 1808 young Struve, who came of a peasant family, in an effort to escape being forced to serve in the armies of Napoleon, then master of Germany, fled first to Denmark, then to the Baltic prov inces of Russia. He entered the University of Dorpat (now Tartu, in the Estonian SSR), ob taining a degree in philology in 1810. He then turned to science and spent the re mainder of his life in Russia. For over twenty years he was director of the ob servatory at Pulkovo, ten miles south of St. Petersburg, an observatory built to his specifications at the order of Tsar Nicholas I. For the observatory, which opened in 1839, he obtained what was then the largest and best refracting tele scope in the world—manufactured by Fraunhofer [450]. Struve spent most of his career in studying double stars, preparing a cata logue of 3,112 of them (three-fourths of them previously unknown), published in 1827, and surveying the Baltic provinces of Russia. His great feat was determining the parallax of Vega, the fourth brightest star in the sky. He was behind both Bes sel [439] and Henderson [505], but not far behind, in this respect. Struve was the first of four generations of well- known astronomers. The fourth of the line, Otto Struve [1203], was an orna ment of American astronomy. In 1964 an observatory named in his honor was established at Tartu. [484] LOBACHEVSKI, Nikolai Ivan ovich (luh-buh-chayf skee) Russian mathematician Born: near Nizhni Novgorod (now Gorki), December 2, 1793 Died: Kazan, February 24, 1856 Lobachevski was the son of a peasant of Polish extraction who died when the boy was six. His widowed mother moved to Kazan and managed to get him schooling on public scholarships. In 1807 he entered the newly established Univer sity of Kazan and proceeded to show re markable mathematical talent. He re ceived his master’s degree in 1812 and in 1814 was placed on the faculty. He quickly rose to important professorial and administrative positions. By 1827 he was president of the university. As such, he was a one-man phenome non. He organized the faculty, library, and laboratories. He even studied archi tecture so as to supervise the building program. He led an effective fight against cholera in 1830 and against a great fire in 1842, saving the university in each case. He wrote many papers on mathe matics but his chief fame was as a math ematical “heretic,” and a colossally suc cessful one. For twenty centuries Euclid [40] and his system of geometry had remained supreme. It was widely as sumed by scholars that mathematics, and geometry in particular, consisted of fun damental truths that existed indepen dently of man. Two and two had to equal four and the sum of the three an gles of a triangle had to be equal to 180°. Nevertheless there was one irritating little imperfection in Euclid. His fifth axiom can be stated in a number of ways, of which the simplest is: “Through a given point, not on a given line, one and only one line can be drawn parallel to the given line.” Unlike Euclid’s other axioms, this one was not at all self-evident and it involved the notion of parallelism, which implied the existence of lines of infinite length. All in all it was a tough nut philo sophically. Many mathematicians, nota bly Saccheri [247], believed that it was too complicated to be an axiom and that it could be proved by means of Euclid’s other and really simple axioms. They all failed. (Mathematicians have come to admire Euclid more for the fifth axiom than anything else. How was it he knew it could not be proved by the other axioms and had to be assumed to begin with?)
325 [484] LOBACHEVSKI MITSCHERLICH
Lobachevski took a daring step. He didn’t wonder if the fifth axiom could be proved. He wondered if it was necessary at all and whether a geometry (perhaps not Euclid’s but a geometry) might not be built without it. The thought occurred to him at least as early as 1826, for he referred to it in his lectures then. He showed if one began with an axiom that stated that through a given point not on a given line, at least two lines, parallel to the given line, could be drawn, then that and the remaining axioms of Euclid could be used to draw up a new, non Euclidean geometry. In the Lobachev- skian geometry the sum of the three an gles of a triangle had to be less than 180°. It was a strange geometry, but it was self-consistent. Lobachevski published his ideas in 1829 and was first in the field. Bolyai [530] worked out a similar geometry in dependently but did not publish until 1832. Gauss [415] had designed such a geometry before either Lobachevski or Bolyai but had not quite had the courage to publish such a defiance of the sainted Euclid. Lobachevski’s geometry, which he in troduced in the West by publishing ele mentary accounts in French and Ger man, was not intended to represent any thing “real”; it was simply a self-consis tent mathematical system. However, a Lobachevskian geometry is to be found on the surface of a curve called a pseudosphere, which is shaped somewhat like a pair of trumpets joined at the flaring ends and with the thinning ends stretching out infinitely. A second type of non-Euclidean geom etry was invented a quarter century later by Riemann [670], Riemann’s geometry was similar to that found on the surface of a sphere. The old-fashioned Euclidean geometry is the geometry found on a plane and is a sort of boundary geometry lying between the two varieties of non Euclidean geometry. And even that fa miliar old geometry underwent a sea change in the hands of Poncelet [456], Philosophically the development of a non-Euclidean geometry shattered the notion of self-evident truth in its most secure stronghold, mathematics. It was made clear that there were a number of truths, depending on the arrangement of axioms one chose to select. One particu lar truth might be more useful than an other under a particular set of circum stances, but it could not be truer. Ham ilton [545] did something of the same sort in algebra. So firm was the hold of Euclid on the minds of men generally, however, (and even on the minds of mathematicians) that the work of Lobachevski and the other non-Euclideans was downgraded and overlooked as much as possible until, three quarters of a century after Lobachevski, Einstein [1064] was able to show that the universe was non Euclidean in structure and that these theoretical concepts had a very practical application. To be sure, the universe is so gently non-Euclidean that over the small seg ments with whiqh scientists ordinarily deal the Euclidean geometry was close enough. (In the same fashion, though the surface of the earth is spherical, a small section of that surface can be treated well enough if it is assumed to be flat.) Lobachevski married a wealthy woman in 1832 and he was ennobled in 1837—but thereafter his life took a downward turn. His reward for revolutionizing mathe matics and the philosophy of science, and for all he had done for the univer sity, was dismissal from his post in 1846. No reason was given. That, together with his worsening eye sight (he was blind in his last years) em bittered his final decade. [485] MITSCHERLICH, Eilhardt (mich'er-likh) German chemist Born: Neuende, Oldenburg (now part of Wilhelmshaven), January 7, 1794
February 28, 1863 Mitscherlich, the son of a minister, was interested in Oriental languages and decided to study medicine because doc
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