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431 [652] KELVIN
KELVIN [652] pies. He assumed that the earth origi nated from the sun and that it was origi nally at the sun’s temperature, but had been cooling olf steadily ever since. Thomson then showed that the time lapse required for the earth to reach modern temperatures had to be between 20 million and 400 million years and was probably about 100 million years. This horrified the geologists, who, since Lyell [502] made uniformitarian principles popular the decade before, believed they needed more time than that, and earth at more or less present temperatures during all that time. This argument between astronomic and geo logic viewpoints was not resolved for over half a century, when the discovery of radioactivity showed that the earth possessed within itself a source of heat independent of the sun, could maintain its temperature for indefinite periods, and might even be heating up. Meanwhile, however, Thomson’s short life-span for the earth together with Helmholtz’s [631] equally short span (suggested for other, equally fallacious reasons) prodded biologists such as Nageli [598] into considering the possi bility of evolution by “jumps,” speeding evolutionary processes and making the history of life fit into a few million years. This bore fruit eventually in De Vries’s [792] mutation theory. Interested in the phenomenon of heat, Thomson was among the first stren uously to support Joule [613], Thomson was, in fact, largely responsible for get ting Joule a reasonable hearing. Later, they collaborated to work out the Joule- Thomson effect, involving the manner in which gases underwent a drop in temper ature when they expanded into a vac uum. This proved a prime factor a gen eration later in Dewar’s [759] liquefac tion of the permanent gases and the obtaining of ultra-low temperatures. (Thomson was also among the first to support Faraday’s [474] concept of lines of force.) Thomson further explored the conse quences of Charles’s [343] discovery that gases lost % 7 3 of their 0° volume for every drop of one centigrade degree in temperatures. He proposed in 1848 that not the volume but the energy of motion of the gas’s constituent molecules reached zero at —273°C. This, in fact, held true of the molecules of all matter, so that Thomson suggested that —273°C be considered absolute zero, a temperature below which no temperature could be. (The modern figure for abso lute zero is —273.18°C.) Furthermore, he proposed that a new scale of temperature be used with its zero mark at the absolute zero and its degrees equal to those on the centigrade scale. Such a temperature scale is re ferred to as the absolute scale, or, in honor of Thomson (and using the title conferred on him), the Kelvin scale. Temperatures on that scale are abbrevi ated as either °A or °K. The notion of an absolute temperature scale was quickly adopted, for it turned out to be very convenient in thermo dynamics. (Rankine [625] introduced a version of it for use by British engi neers.) For instance, the demonstration of Carnot [497] that the maximum work to be obtained from a heat engine de pended on temperature differences within the engine could be most neatly expressed if the absolute scale was used. It is now universally accepted that at ab solute zero the energy of motion (or ki netic energy, a term introduced by Thomson in 1856) of molecules is virtu ally zero. Maxwell [692] carried this no tion of kinetic energy of molecules fur ther, interpreting temperature in terms of that concept and evolving the kinetic theory of gases, in which heat was es tablished as a form of motion. In 1851 Thomson deduced from Car not’s work the proposition that all energy tends to dissipate itself as heat, that it “runs down” into an unusable form. He pictured this continuous “degradation” of energy as a sign that the whole uni verse was running down. This is another form of the second law of thermo dynamics and was similar to the concept of entropy advanced somewhat more precisely by Clausius [633] at about the same time. Those were the years when Field [621] was putting his heart and fortune into laying the Atlantic cable, and it was 4 3 2
[653] BROCA
BROCA [653] Thomson who studied the capacity of a cable to carry an electric signal. He in vented improvements in cables and gal vanometers, without which the Atlantic cable would have been useless. In 1866 he was knighted because of his achieve ments in this respect. He also introduced Bell’s [789] telephone into Great Britain. In later life he made numerous inven tions, including improvements in the mariner’s compass, new types of sound ing gauges, tide predictors, and so on. From 1890 to 1894 he was president of the Royal Society. It is sometimes the fate of scientists who in their youth forged new trails and led the way toward new concepts to pass their last days bewildered by still newer developments they cannot accept. In the 1880s Thomson settled down to immobility, yet within a decade the Sec ond Scientific Revolution burst upon the world and more new aspects of physics have been uncovered in any one decade since than in all the two centuries be tween Newton [231] and Thomson. Thomson lived long enough to see the beginning of this revolution but could not appreciate its significance. With al most his last breath, as an old man in his eighties, he, who had been so brilliantly revolutionary in his youth, set his face against novelty and bitterly opposed the notion that radioactive atoms were disin tegrating or that the energy they released came from within the atom. In 1892 Thomson was raised to the peerage as Baron Kelvin of Largs, a title (borrowed from the Kelvin River near Glasgow) that died with him, for he left no heirs. He was buried in Westminster Abbey next to Newton. [653] BROCA, Pierre Paul French surgeon and anthro pologist
Born: Sainte-Foy-la-Grande, Gironde, June 28, 1824 Died: Paris, July 9, 1880 Broca obtained his medical degree from the University of Paris in 1849 and then specialized in brain surgery. He was the first to trepan (cut through the skull) so as to treat an abscess on the brain. He demonstrated in 1861 through postmortems that damage to a certain spot on the cerebrum (the third con volution of the left frontal lobe, or Broca’s convolution) was associated with the loss of the ability to speak (aphasia). This was the first clear-cut demonstration of a connection between a specific ability and a specific cerebral point of control. Within twenty years much of the cerebrum was mapped out and associated, piece by piece, with por tions of the body. Gall’s [371] insight, which had been misdirected into phrenol ogy, was thus put right. Broca’s hobby was anthropology and he founded anthropological societies, an thropological journals, and even an an thropological school. This is not strange, for much of the work done by anthro pologists at the time involved skull mea surements (craniometry) and followed Retzius’ [498] distinction among races on the basis of such measurement. Broca knew more about the skull than anyone else in his time and put his knowledge to practical anthropological use by devising new instruments for craniometric mea surements. Meanwhile in 1856 an old skull had been unearthed in the Neanderthal (a valley near Düsseldorf in the Rhine land). It was clearly a human skull, but it was more primitive and apelike than any modern skull. From the stratum in which it was located, it had to be quite old, and a controversy at once arose. Was it an early primitive form of man that later evolved into modem man? Huxley [659] thought so. Or was it sim ply an ordinary savage of ancient days with congenital skull malformation, or one who had suffered a bone disease? Virchow [632], himself an amateur an thropologist, maintained the latter. The publication of Darwin’s [554] Ori gin of Species intensified the argument, since if the skull really belonged to a primitive pre-man, then the notion of ev olution would be strengthened at its most sensitive point, that of possible human evolution. Not only would there be Boucher de Perthe’s [458] ancient tools, but there would be ancient man to make 433 [654] RICHTER
BATES [656] them, and not even a full man, but a creature at an earlier stage of develop ment.
Broca, the most prominent French sci entist to become an early supporter of Darwin, insisted that the skull actually represented a primitive Neanderthal man and he carried the day eventually. The dispute was not laid entirely to rest, however, until the discovery by Dubois [884] a generation later of manlike skele tal remains in Java that were far more primitive than the Neanderthal. Just before his death, Broca was ap pointed a member of the French senate. [654] RICHTER, Hieronymus Theodor (rikh'ter) German mineralogist
ber 21, 1824 Died: Freiberg, Saxony, Septem ber 25, 1898 Richter was Reich’s [506] assistant at the Freiberg School of Mines, and in 1875, some years after Reich had re tired, Richter became director of the school. His great feat was spotting the indigo-colored line in a spectrum that led to the discovery of indium. Although he did this at Reich’s direction, Richter later tried to make it seem that indium was his discovery alone. [655] FRANKLAND, Sir Edward English chemist Born: near Church town, Lan cashire, January 18, 1825 Died: Golaa, Norway, August 9, 1899
Frankland, of illegitimate birth, was originally a druggist’s apprentice, taught himself chemistry, then managed to enter the field professionally. He went to Germany where he met Kolbe [610] and where Liebig [532] and Bunsen [565] were among his teachers. He obtained his Ph.D. at Marburg in 1849, then be came professor of chemistry at Owens College in Manchester and, in 1857 in St. Bartholomew’s Hospital in London. In 1865 he succeeded Hofmann [604] at the Royal College of Chemistry. He was the first to study those hybrid molecules, the organometallic com pounds. Until his time, the known or ganic substances were composed of non metallic elements only: carbon, hydro gen, nitrogen, oxygen, sulfur, phos phorus, and so on, with a few exceptions among the large protein molecules. Bun sen had moved a step onward, studying organic molecules containing the semi metal, arsenic. Frankland went on to prepare small organic molecules of which atoms of true metals such as zinc formed integral parts. This was done in 1850 and was enough to attain for him the professorship at Owens College. Organometallic compounds were to make possible the important Grignard [993] reactions a half century later. Fur thermore, his study of such compounds led Frankland to devise the theory of valence and to announce it on May 10, 1852; the theory, that is, that each type of atom has a fixed capacity for combin ing with other atoms. This led not only to the Kekul6 [680] structures, but also to the periodic table of Mendeleev [705], since that table was based on the regular change of valence with atomic weight. Beginning in 1868 Frankland did a great deal of highly practical work on river pollution, a subject gaining great importance in industrial England (and becoming ever more important since). He retired in 1885, received the Copley medal of the Royal Society in 1894, and was knighted in 1897. Two years later he died while on holiday. [656] BATES, Henry Walter English naturalist Born: Leicester, February 8, 1825
Died: London, February 16, 1892
Bates, the son of a hosiery manufac turer, did not have much chance at an education before going to work in the hosiery business. Even though he had a thirteen-hour workday, he managed to 4 3 4
[657] SCHULTZE
HUXLEY [659] go to school at night. Entomology was, and remained, his hobby. In 1844 Bates became friendly with A. R. Wallace [643]. Bates got Wallace interested in entomology and Wallace eventually suggested a trip to tropical forests where they might collect speci mens and learn something about the ori gin of species. (This was before Wallace solved the problem along with Darwin [554].)
In 1848, following up this audacious scheme, the two friends landed in Brazil at the mouth of the Amazon. Wallace re turned in 1852 but Bates remained for a total of eleven years, most of it in the virtually unknown upper reaches of the river. He collected over 14,000 animal species, mostly insects, more than 8,000 of which had not hitherto been known to Europeans. Soon after he returned, Darwin’s The
Bates accepted it wholeheartedly. In fact, Bates presented a great deal of informa tion on insect mimicry, based on his Amazonian collection, that went a great way toward backing Darwinian notions. One cannot suppose that one insect spe cies will imitate another in appearance on purpose; but it is easy to see that if such an imitation is beneficial, then those individuals that come closer to imitation through random variation will survive to have young more readily than those that do not and that in time, through natural selection, the mimicry will become very close and effective. [657] SCHULTZE, Max Johann Sigis mund (shool'tsuh) German anatomist
Schultze studied at the University of Greifswald where his father was an anat omy professor. He also attended lec tures by J. P. Müller [522] at the Uni versity of Berlin. He obtained his medi cal degree from Greifswald, then taught at Halle University from 1854. In 1859 he became director of the anatomical in stitute at Bonn, where he remained the rest of his life. He was particularly interested in pro toplasm, the colloidal matter within the cell, and was able to show that it had nearly identical properties in all kinds of cells. Protoplasm he described, in what became a famous phrase, as the “physi cal basis of life.” [658] BALMER, Johann Jakob Swiss mathematician and physicist Born: Lausen, Basel-Land, May 1, 1825
Died: Basel, March 12, 1898 Balmer, the son of a judge, obtained his doctorate at the University of Basel in 1849 and lived a quiet life in Basel, teaching at a girls’ school. Relatively late in life he became interested in spectra and reported his first piece of research at the age of sixty. It had seemed that the lines in the solar spectrum are scattered randomly, but once Kirchhoff [648] called attention to the spectra of individual elements, greater regularity could be found. The spectrum of glowing hydrogen particu larly had a series of lines spaced more and more closely with decreasing wave length. Balmer, applying his mathe matical bent to this, devised a formula of rather simple form that could give the wavelengths of all the series. He an nounced this in 1885. The formula was purely empirical and Balmer offered no explanation for its ex istence. A generation later, however, it became of crucial importance when Bohr [1101] (who was bom in the year in which the formula was announced) used it as the chief evidence in favor of his theory of the internal structure of the hydrogen atom. [659] HUXLEY, Thomas Henry English biologist Born: Ealing, Middlesex, May 4, 1825
Died: Eastbourne, Sussex, June 29, 1895 435 [659] HUXLEY
ERLENMEYER [661] Huxley, the son of an unsuccessful schoolmaster, had only two years of schooling himself. Nevertheless, he edu cated himself to the point where he could enter medical school. He obtained his medical degree from London Univer sity in 1845 and then traveled as ship’s surgeon on a voyage to Australia be tween 1846 and 1850. As in the case of Darwin [554] and Wallace [643], his in terest in natural history became all con suming. It was he who named the phy lum Coelenterata, to which jellyfish be long, and in 1851 he was elected to the Royal Society. In 1854 he was appointed professor of natural history at the Royal School of Mines, where he delivered enormously popular lectures that he ac tively—and successfully—aimed at the lower classes. He thus found his true vo cation as a popularizer of science. In 1858 he finally disproved the theory of the origin of the skull from the ver tebrae, a theory that began with Goethe [349] and Oken [423] and that still had its attractions for the nature philosopher Owen [539]. He was a late convert to Schwann’s [563] cell theory. When Huxley read The Origin of Spe cies he became at once an ardent expo nent of Darwinism. (“Now why didn’t / think of that?” he is reported to have asked in annoyance.) Since Darwin could not or would not fight, Huxley took to the lecture platform with enthu siasm. In 1860, at a meeting of the Brit ish Association for the Advancement of Science at Oxford, he faced the Bishop of Oxford, Samuel Wilberforce (called Soapy Sam because of his unctuous way of speaking), who was primed with “facts” by Owen and who asked sarcas tically if Huxley traced his own descent from the apes through his father or mother.
Before an overflow crowd of seven hundred, Huxley answered with deep disdain that if he had to choose as an ancestor either a miserable ape or an educated man who could introduce such a remark into a serious scientific discus sion, he would choose the ape. Exit Wil berforce. Huxley invented a word to describe his religious beliefs. He called himself an "agnostic.” He spent the rest of his life as a writer on popular science and on religious questions, and served as presi dent of the Royal Society from 1881 to 1885, but the great feat of his life was the popularization of Darwinism. [660] BOND, George Phillips American astronomer Born: Dorchester (now part of Boston), Massachusetts, May 20, 1825
February 17, 1865 The younger Bond cut his eyeteeth assisting his father, W. C. Bond [464], in the observatory and succeeded to the directorship on his father’s death. He specialized in the solar system, discover ing a number of comets. In 1848 with his father he discovered Hyperion, an eighth satellite of Saturn. Here, again, as in the crape ring, the Bonds anticipated Lassell [509] by a matter of days. In 1856 the younger Bond pointed out that the brighter a star the larger the image it made on a photographic plate (through its effect on silver bromide grains over a larger area) and showed that estimates of stellar magnitude could be made from such photographs. In 1857 he photographed the double star Mizar, showing both components on the film. This was the first double-star photography. Bond succeeded his father as director of Harvard Observatory on the latter’s death in 1859, but he himself died at the age of thirty-nine of tuberculosis, having held the position only six years. [661] ERLENMEYER, Richard August Carl Emil (er-len-my'er) German chemist
January 22, 1909 Erlenmeyer entered the University of Giessen in 1845, intent on a medical ca reer. However, he heard Liebig [532] lecture and was converted to chemistry. Download 17.33 Mb. Do'stlaringiz bilan baham: 
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