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356 [543] JACKSON
FITZROY [544] between the watery, nonliving sap in the center of the cell and the granular, col loidal material rimming the cell. This latter portion, which he recognized as living, he called protoplasm, adapting Purkinje’s [452] word. It was an easy step from that to using the word for the granular colloidal mate rial within all cells generally, something Remak [591] was soon to do. He was the first to propose that new cells sprang from cell division and pro vided the first clear explanation of os mosis, whereby liquid moves from a less concentrated side across a membrane to a more concentrated side. [543] JACKSON, Charles Thomas American chemist
June 21, 1805 Died: Somerville, Massachusetts, August 28, 1880 Jackson could trace his ancestry to the
the philosopher, Ralph Waldo Emerson. He obtained his medical degree from Harvard in 1829, but after 1836 prac ticed no more. Like the far greater Hooke [223] a century and a half earlier, he was a man with a restless mind, given to starting jobs and not finishing them, and a bear for controversy besides. He was interested in geology as well as medicine and chemistry and he made geological surveys of various parts of New England between 1837 and 1844. He experimented with ether, breathing himself into insensibility, and instructed Morton [617] in the proper method of administering it. He was enraged when Morton went ahead and achieved fame. Jackson began a long and pertinacious quarrel over priority. He engaged in a similar quarrel over priority with Morse [473] in connection with the telegraph and also insisted on claiming himself the true discoverer of the explosive, guncotton. Madness was never far below the surface with him, and in 1873 it took over completely. He remained insane for the rest of his life. [544] FITZROY, Robert (fits-roy') English meteorologist Born: Ampton Hall, Suffolk, July 5, 1805
Died: Upper Norwood, London, April 30, 1865 Fitzroy was a descendant of an illegit imate child of Charles II, and his family had a seafaring tradition. He entered the Royal Naval College in 1819 and was commissioned a lieutenant in 1824. In 1828 he was put in command of the Beagle and ordered to undertake the surveying of the southern coasts of South America. On a second voyage for the purpose, beginning in the summer of 1831, Fitzroy chose as his scientific aide, the young Charles Darwin [554]. Be cause of this, the second voyage of the
volved the circumnavigation of the world, became possibly the most impor tant voyage (from the scientific stand point) in history, and Fitzroy is known, almost exclusively, for his relationship to Darwin. Fitzroy, a moody man, and given to deep depressions, was a hard man to get along with and even the equable and gentle Darwin couldn’t manage to do it. What’s more, Fitzroy, ardently religious, was pained by Darwin’s interpretations of his discoveries on the voyage and was horrified by his theory of evolution when it was announced. Fitzroy was a more than competent navigator and surveyor, however, who fulfilled his task magnificently, and in 1837 fully deserved the gold medal voted him by the Royal Geographic Society. During the voyage he grew interested in meteorology and, in 1855, was placed in charge of the Meteorologic Office with instructions to gather weather informa tion for the use of shipping. Fitzroy made barometers available to ships’ cap tains, gathered information from them, issued weather forecasts which were printed daily in the London Times. (He was the first to do this and even popu larized the term.) He was always in volved in controversy, however (much of it his own doing), and in the end killed himself.
[545] HAMILTON
LAMONT [546] [545] HAMILTON, Sir William Rowan Irish mathematician
Dublin, September 2, 1865 Hamilton, the son of a solicitor, was a child prodigy who attended no school and was largely self-taught. He force-fed himself a vast number of languages, fourteen of them to be exact, including such useless ones—for an Irishman who was not to become an Orientalist—as Persian, Malay, and Sanskrit. He was also, like Davy [421], an amateur poet, numbering Samuel Taylor Coleridge and William Wordsworth among his friends. He grew interested in Newton’s [231] Principia at twelve and began to feel himself devoured by a growing interest in mathematics. He taught himself the subject and at the age of seventeen as tonished the royal astronomer in Ireland by communicating to him his discovery of a mathematical error in Laplace’s [347] Celestial Mechanics. This paid off, for at twenty-two he was appointed professor of astronomy at Trinity College in Dublin (after having finally entered the school for his first bit of formal education and graduating with highest honors in classics and mathe matics). He accepted the position on the understanding that he could work freely in mathematics. This was worthwhile too, for he soon produced an important mathematical work on optics that helped establish the wave theory of light. His most important work, however, was in 1843 on what are called quater nions. The idea for this came to him in a flash of inspiration during a walk to town with his wife. It seems that Gauss [415] had treated imaginary numbers in combination with real ones as representing points on a plane and showed the methods by which such complex numbers could be manipu lated. Hamilton tried to extend this to three dimensions and found himself un able to work out a self-consistent method of manipulation, until it occurred to him that the commutative law of multi plication need not necessarily hold. It is taken for granted that A times B is equal to B times A (that is, if 8 X 6 is 48, so is 6 x 8) and this is an example of what seems to be an eternal and inescap able truth. Hamilton, however, showed that he could build up a logical algebra for his quaternions only when B times A was made to equal—A times B. This seems against common sense but, like Lobachevski [484], Hamilton showed that truth is relative and depends on the axioms you choose to accept. The time was to come, three quarters of a century later, when a noncommutative algebra was to form the basis for quan tum mechanics and for the proper un derstanding of the internal structure of the atom. Hamilton was knighted in 1835, while he was still young and full of promise. However, he remained poor, his marriage was unhappy, and his wife was an invalid. The last third of his life was wasted through alcoholism. [546] LAMONT, Johann von (lah'- mohnt) Scottish-German astronomer Born: Braemar, Aberdeenshire, Scotland, December 13, 1805 Died: Munich, Germany, August 6, 1879
At the age of twelve, Lamont was sent to Bavaria for an education at a Scottish Benedictine monastery and he remained there the rest of his life, adopting Ba varian nationality. In 1827 he began working in a new observatory at Bogen hausen. He prepared a star catalogue containing nearly thirty-five thousand stars, but his main interest was in the earth’s magnetic field. He measured the intensity of that field all over Europe and from these and pre vious records decided that this intensity rose and fell in a ten-year period, a re sult he published in 1862. It was easy to see that this period coincided roughly with Schwabe’s [466] sunspot cycle. The connection between the two cycles re mained completely mysterious, however, until the discovery of charged subatomic particles and the investigation of the earth’s ionosphere half a century later 358 [547] GRAHAM
GRAHAM [547] brought a new view of earth-sun interac tion. He also determined the mass of Uranus as well as the orbital details of several of the satellites of Saturn and Uranus. [547] GRAHAM, Thomas Scottish physical chemist Born: Glasgow, December 21, 1805
Died: London, September 16, 1869
Graham was headed for the ministry by his father, a prosperous manufac turer, but at the University of Glasgow he was converted to science. When his angry father withdrew his financial sup port, Graham, nothing daunted, sup ported himself by teaching and writing and continued right on. He graduated in 1826 and by 1830 was professor of chemistry at that institution. In 1837 he accepted a similar post at University Col lege in London. In 1841, the Chemical Society of London was founded (the first such organization formed on a na tional basis) and Graham became its first president. Graham’s early interest was in the diffusion of gases. Thus, if hydrogen is placed in the top half of a container and oxygen in the bottom half, the two gases are eventually thoroughly mixed even though the oxygen, being heavier, should stay at the bottom if gravity is the only force to be considered. (The kinetic theory of gases, eventually established by Maxwell [692], showed quite well that a second force arose from the rapid, ran dom motion of the gas molecules, which moved in highly zigzag bouncy fashion in all directions, so that some hydrogen eventually made its way downward and some oxygen upward in defiance of grav ity.) In the 1820s, when Graham began his studies on diffusion, the kinetic theory was still a generation in the future. How ever, he came across an observation by Dobereiner [427] that a cracked bottle with hydrogen in it, inverted and with its mouth submerged in water, lost hydro gen faster than it gained air so that the water level rose. Graham followed this up. He worked empirically and measured the rate at which gases diffused through a plaster of Paris plug, through fine tubes, and through a tiny hole in a plati num plate. In this way he cut down the rate of diffusion and made it easily mea surable, as once Galileo [166] had cut down the rate of free fall by using an in clined plane. By 1831 he found that the rate of diffusion of a gas was inversely propor tional to the square root of its molecular weight. Thus since oxygen molecules are sixteen times as massive as hydrogen molecules, hydrogen diffuses four times as quickly as oxygen. This is still called Graham’s law. Through this discovery Graham may fairly be reckoned one of the founders of physical chemistry. In 1854 he left teaching to become master of the mint (as Newton [231] and John Herschel [479] had done be fore him; in fact he succeeded Herschel on the occasion of the latter’s nervous breakdown). Graham continued his re searches, however. His early studies on diffusion led even tually to something of still greater impor tance. Graham was interested in the manner in which molecules diffused through a solution. A crystal of copper sulfate at the bottom of a cylinder of water will dissolve, and the blue color of the copper sulfate will slowly spread up ward through the cylinder. Graham no ticed that here too some substances diffused more slowly than others. In 1861 he tried the same device as before and put a blocking substance in the way of the diffusing materials. In this case it was a sheet of parchment. He found that substances like salt, sugar, and copper sulfate, which diffused com paratively rapidly, would pass through the parchment and be detectable on the other side. On the other hand, materials such as gum arabic, glue, and gelatin, which diffused exceedingly slowly, would not pass through the parchment. He distinguished, therefore, two classes of substances. The materials that diffused through the parchment were easily crystallizable materials, so he
[547] GRAHAM
MAURY [548] called them crystalloids. Those that did not diffuse through were not known, in Graham’s time, to exist as crystals. He took glue (in Greek, kolla) to be a typi cal member of this second group, which he therefore called colloids. He further showed that a colloidal ma terial could be purified and crystalloidal contamination removed by placing the material inside a container made of a porous membrane, which is in turn placed in running water. The crystalloids pass through and are washed away, while the colloids remain behind. This process he termed dialysis, and the pas sage through such a membrane he named osmosis. As we now know, the difference be tween the crystalloids and colloids is largely a matter of particle size. The diffusing crystalloids are made up of relatively small molecules, while colloids are made up of relatively large mole cules, or of relatively large aggregates of small molecules. This has turned out to be of particular importance to biochem ists since the most important molecules of living tissue, such as proteins and nucleic acids, are of colloidal size. The study of protoplasm is, therefore, a foray into colloid chemistry, a science of which Graham is considered the founder.
Between these two journeys into the world of diffusion, Graham in 1833 studied the various forms of phosphoric acid and showed that they differed in hy drogen content. In metaphosphoric acid, one hydrogen atom per molecule can be replaced by a metal; in pyrophosphoric acid, two can be replaced; and in ortho phosphoric acid, three. This introduced chemists to the existence of polybasic acids; that is, those with molecules in which more than one hydrogen atom could be replaced by metals. Graham also studied the presence of water molecules in crystals of various compounds (water of crystallization) and the manner in which the metal pal ladium absorbed large quantities of hy drogen. He was also the first to suggest that al cohol intended for nondrinking use be adulterated with poison (“denatured al cohol”) to prevent unauthorized drink ing—or to punish it. [548] MAURY, Matthew Fontaine American oceanographer Born: near Fredericksburg, Vir ginia, January 14, 1806 Died: Lexington, Virginia, Febru ary 1, 1873 Maury, the son of a small planter, fol lowing in the footsteps of an older brother, entered the navy as a midship man at the age of eighteen and by 1830 had circumnavigated the world. He might not have been heard of in the world of science had he not in 1839 been permanently lamed in a stagecoach accident. He was retired from active duty and given the sinecure of superin tendent of the Depot of Charts and In struments. A sinecure, however, is never a sine cure without the consent of the man who holds the post, and Maury did not give his consent. He threw himself into the study of ocean winds and currents and distributed specially prepared logbooks to captains of ships so that he might collect further data. Out of his work there grew the United States Naval Ob servatory. He was also one of the founders of the American Association for the Advancement of Science. In particular he studied the course of the Gulf Stream (which had been stud ied by Benjamin Franklin [272] as early as 1769) and gave it a description that has become classic: “There is a river in the ocean.” His researches received inter national recognition when ocean voyages were shortened as captains learned how to take advantage of the currents instead of fighting them. In 1850 he worked up a chart of ocean depths to facilitate the laying of the transatlantic cable, so that both on the surface and in the deep he may be considered among the founders of oceanography. In the course of this project, he noted the Atlantic was shal lower in the center than on either side. This was the first indication of the Mid Atlantic Ridge whose true nature was to become apparent a century later. Maury 360 [549] DE MORGAN PALMIER!
called the shallow region “Telegraphic Plateau.” It quickly became apparent that a proper study of the earth’s vast ocean required international cooperation and Maury was the moving figure behind an international conference held in Brussels on the subject in 1853. In 1855 he pub lished the first textbook in oceanography, Physical Geography of the Sea. It was extremely successful in its own time but was marred by Maury’s refusal to con sider evolutionary aspects of oceanog raphy because of his insistence on ac cepting the literal words of the Bible. The coming of the American Civil War interrupted Maury’s researches. As a Virginian he followed his state out of the Union and became the head of coast, harbor, and river defenses for the Con federacy. He invented an electric tor pedo and went on missions to England for supplies. With the war over and the Confed eracy defeated, Maury thought it wise to go into voluntary exile. For a while he was in Mexico with the Emperor Max imilian trying to establish a colony of Virginians; but Maximilian too was a doomed cause and Maury went to En gland. By 1868 emotions had cooled to the point where Maury could return to the United States, accept a professorship of physics at the Virginia Military Insti tute, and pass his last years in peace. His forgiveness by the United States is total. At the Naval Academy at Annapo lis there stands Maury Hall, named in his honor, even though for four years, following his own concept of patriotism, he would have destroyed the American navy if he could. He was elected to the Hall of Fame for Great Americans in 1930. [549] DE MORGAN, Augustus English mathematician Bom: Madura, Madras, India, June 27, 1806 Died: London, March 18, 1871 De Morgan was the son of an English colonel serving in India and was taken to England when he was seven months old. De Morgan entered Cambridge in 1823 and graduated in 1827. The following year, with the strong recommendations of Airy [523] and Peacock [472] under whom he had studied, he was granted a professorial position at University Col lege, London. De Morgan labored to strengthen the logical bases of mathematics, for since ancient Greek times mathematics had rested on a foundation of unspoken as sumptions that were not necessarily wrong but were not examined either. De Morgan began a process that was to con tinue through Bertrand Russell [1005] in which as many formal definitions of things that seem self-evident are given, and in which undefinable assumptions are clearly stated. His greatest work was in logic, for he began the process of extending Aristot le’s [29] work in the field. He pointed out that Aristotle dealt clearly with all and with none but was shaky over state ments that made use of some. De Mor gan worked out a careful set of symbols to be used in such statements of “Some x’s are y’s.” (As, for instance, “some people are wearers of brown trousers.”) De Morgan’s work in this field led within a few years to Boole’s [595] broader and more systematic develop ment of what came to be known as sym bolic logic. Boole admitted his debt to De Morgan. [550] PALMIERI, Luigi (pahl-myeh'ree) Italian physicist
Palmieri obtained his degree in archi tecture and at first taught at a secondary school, though he eventually became a professor of physics at the University of Naples and worked at the Mount Vesu vius Observatory. He was particularly interested in earth sciences and invented a number of in struments for the measurement of rain fall. He also invented a device for the detection of minor earthquakes. This consisted of horizontal tubes, turned up at the end and partly filled with mercury. Download 17.33 Mb. Do'stlaringiz bilan baham: 
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