Biographical encyclopedia
[314] MESMER BERGMAN [315]
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[314] MESMER
BERGMAN [315] and affecting the lives of human beings. In any age he would have been inter ested in whatever ill-understood phenom enon was claiming the attention of scholars. In the late eighteenth century this meant electricity and magnetism, and as a physician he naturally at tempted to turn these forces to the cur ing of disease. He began by passing magnets over the bodies of his patients and managed to effect cures in some cases. Later he dis covered that magnets were unnecessary and that the same happy results could be achieved by the simple passing of hands. He decided that in the latter case he was making use of “animal magnetism.” His practice in Vienna was not with out troubles. His undoubted cures (well advertised by doctor and patient alike) were mixed with failures. The patients who suffered these failures naturally felt aggrieved, and charges of malpractice multiplied. The unsympathetic police or dered Mesmer to move on. He went to Paris in 1778 and there became the rage. The volatile French so ciety of the day, in the twilight of the Age of Reason, was ready for any nov elty expressed in scientific-sounding words. Orthodox Parisian doctors were naturally enraged, and eventually a com mission of experts investigated Mesmer’s methods. Among the experts was Ben jamin Franklin [272], who was then in Paris representing the brand-new United States, Lavoisier [334], and Joseph Guil- lotin, the inventor of the guillotine. The experts reported unfavorably and in 1785 Mesmer was forced to leave Paris. He retired to Versailles, then to Swit zerland, then to his native region, and obscurity. (Franklin, by the way, al though denying the validity of Mesmer’s work, made it clear he felt that cures could be effected by suggestion and went on to discuss psychosomatic ailments in almost modern terms.) Although Mesmer was 90 percent gobbledygook, he was in earnest and there is no reason to doubt that his cures were genuine. His followers raised the gobbledygook percentage to 100, but it remains clear, in retrospect, that Mesmer was curing psychosomatic ailments by suggestion. His methods, refined and freed of some of their mumbo-jumbo, became respectable once more a half century later when Braid [494] rein troduced what he called hypnotism. An accepted synonym for hypnotism is, even today, mesmerism, in honor of the Aus trian doctor. [315] BERGMAN, Torbem Olof Swedish mineralogist Born: Katrineberg, Vastmanland, March 9, 1735 Died: Medevi, July 8, 1784 Bergman, the son of a tax collector, obtained his doctor’s degree at the Uni versity of Uppsala in 1758. Though a physicist and mathematician as well as a chemist, he was chiefly interested in min eral classification, which is not surpris ing, considering that he had studied under that great classifier Linnaeus [276].
Bergman based his classification on chemical characteristics rather than on appearance alone, as his older contem porary Cronstedt [292] was also doing. Bergman evolved a theory to explain why one substance reacted with a second but not, perhaps, with a third, by sup posing the existence of “affinities” (that is, attractions) between substances in varying degrees. He prepared elaborate tables listing affinities, and they were very influential during his lifetime and for a few decades after. He also attempted to produce exact determinations of mineral composition (“quantitative analysis”) by producing precipitates and weighing them accu rately (“gravimetric determinations”). Yet neither these things nor such specific discoveries as the fact that car bon dioxide possessed acidic properties in solution is what he is best remem bered for. His greatest discovery was a human being, Scheele [329], the apothe cary of genius whom Bergman helped and encouraged. Bergman was forced into retirement in 1780 because of bad health, and died of tuberculosis before he was fifty.
[316] WATT
WATT [316]
[316] WATT, James Scottish engineer Born: Greenock, Renfrew, Janu ary 19, 1736 Died: Heathfield, near Birming ham, England, August 19, 1819 Watt was a rather sickly child who could not go to school and was taught to read and write by his mother. He suffered from chronic migraine head aches and was suspected of being men tally retarded. His mother died while he was in his teens and his father, originally a prosperous merchant, experienced hard times that grew progressively worse. Watt traveled to England, reaching Lon don eventually, and there went through a hard year of apprenticeship, during which he learned the use of tools and the craft of instrument maker. In 1756 he returned to Scotland and tried to establish himself as an instru ment maker in Glasgow. However, he did not meet the municipal require ments, for he lacked a sufficient period of apprenticeship, so he obtained a posi tion at the University of Glasgow, which was outside municipal jurisdiction. There he met Joseph Black [298] and learned of the matter of latent heat. Un doubtedly this set him to thinking how steam engines might be improved. Sa- very [236] and Newcomen [243] had devised engines that were in use as power sources for water pumping. How ever, such machines were terribly inefficient. This had been brought forci bly to Watt’s attention when in 1764 the university gave him a model of a New comen steam engine to repair after a London instrument maker had failed. Watt could repair it without trouble, but that was not enough for him. He wanted to improve it. During the course of a thoughtful Sun day walk, it seemed to him that he per ceived the chief source of inefficiency. In the Newcomen engine, the steam cham ber was cooled to condense the steam and produce the vacuum. It then had to be filled with steam again, but, since it had been cooled, a great deal of steam was first necessary just to heat up the chamber. All that steam was wasted. At every cycle, immense quantities of fuel were required to undo the work of the cold water. Watt introduced a second chamber (a “condenser”) into which the steam could be led. The condenser could be kept cold constantly while the first chamber (the “cylinder”) was kept hot constantly. In this way the two processes of heating and cooling were not forced to cancel each other. By 1769 Watt had a steam engine working with greater efficiency than the Newcomen variety. Further more, since there was no long pause at each cycle to heat up the chamber, Watt’s engine did its work much more quickly. So impressed was Black with this development that he lent him a large sum of money to keep the project in op eration.
Watt introduced other ingenious im provements, such as allowing steam to enter alternately on either side of a pis ton. Previously air pressure had driven the piston rapidly in only one direction as a vacuum was produced when steam was condensed. It was only mounting steam pressure, then, that slowly moved it back in the other direction. With steam entering and condensing on both sides, air pressure drove the piston rap idly in both directions alternately. In 1774 Watt went into partnership with a businessman and began to manufacture steam engines for sale. (In 1784 he used steam pipes to heat his office, so he also invented “steam heat.”) By 1790 the Watt engine had com pletely replaced the older Newcomen va riety and by 1800 some five hundred Watt engines were working in England. In fact so superior was the Watt engine that the very existence of the Newcomen engine was all but forgotten and Watt began to be looked upon as the inventor of the steam engine. In a sense, however, this was justified, for Watt not merely improved the New comen engine, he was the first to make such an engine more than a pump. In 1781 he devised mechanical attachments that ingeniously converted the back and forth movement of a piston into the ro tary movement of a wheel, and by one type of movement or the other, the
[316] WATT LAGRANGE
[317] steam engine could then be made to power a variety of activities. Soon iron manufacturers were using it to power bellows to keep the air blast going in their furnaces and to power hammers to crush the ore. The now-versatile steam engine had thus become the first of the modem “prime movers,” the first modem device, that is, to take energy as it occurred in nature (in fuel) and apply it to the driv ing of machinery. It was just at this time, too, that the textile industry, En gland’s most important, was being mech anized by men such as Arkwright [311]. The steam engine proved to be the right invention at the right time. The consequences were incalculable. Steam engines, powered by burning coal, could deliver large quantities of energy constantly, at any needed spot. Manufac turing locations were not confined to rapid streams where water power might be used. Large and massive machinery, powered by steam, could be constructed and housed in factories. Large-scale pro duction in such factories made handwork at home uneconomical. The artisan was replaced by the factory worker. Cities mushroomed; slums boomed; farming withered. All the benefits and evils of the factory system blossomed. In short, the Industrial Revolution began. Watt started another revolution, which, however, was not to bloom for a century and a half. He invented a “cen trifugal governor” that automatically controlled the engine’s output of steam. The steam output whirled the governor about a vertical rod. The faster it whirled, the farther outward were thrown two metal spheres (through the action of centrifugal force). The farther outward the balls were thrown, the more they choked off the steam outlet. The steam output thus decreased, the gover nor whirled more slowly, the spheres dropped and the outlet was widened. In this way the steam output hovered be tween two limits and was never allowed to grow too large or too small. In this is the germ of automation, since the centrifugal governor was a de vice that controlled a process by means of the variations in the process itself. Automation has not come into its own until recent decades, but it began with James Watt, and the word governor, via the Greek, has given us the modem term “cybernetics.” Watt enjoys one honor that arose out of his efforts to measure the power (that is, the rate of doing work) of his steam engine. In 1783 he tested a strong horse and decided it could raise a 150-pound weight nearly four feet in a second. He therefore defined a “horsepower” as 550 foot-pounds per second. This unit of power is still used. However, the unit of power in the metric system is called the watt, in honor of the Scottish engineer. One horsepower equals 746 watts. In 1800, prosperous, successful, and respected, Watt retired. He received an honorary doctorate from Glasgow Uni versity and was elected to the Royal So ciety. He refused the offer of a baron etcy and lived to be the last survivor among the founders of the famous Lunar Society of Birmingham, to which Priestley [312] and Erasmus Darwin [308] had belonged. [317] LAGRANGE, Joseph Louis, comte de (la-grahnzh') Italian-French astronomer and mathematician
25, 1736 Died: Paris, France, April 10, 1813
Lagrange was of French ancestry, though born and raised in the Italian kingdom of Piedmont. His parents were wealthy but his father had speculated his fortune into oblivion. He was the youngest of eleven children and the only one to survive to adulthood. His father intended him for the law, but at school he came across an essay by Halley [238] on the calculus and was at once con verted to mathematics. By the age of eighteen he was teaching geometry at the Royal Artillery School in Turin. There he organized a discussion group that be came the Turin Academy of Sciences in 1758.
Lagrange’s mathematical ability was 209 [317] LAGRANGE
LAGRANGE [317] recognized by Euler [275], who at that time headed the Berlin Academy of Sci ences under Frederick II (a monarch who rifled all Europe for scientific talent). In 1755 Lagrange had sent Euler a memorandum on the “calculus of vari ations” on which Euler himself had been working. So impressed was Euler that he deliberately held back his own work to allow Lagrange to publish first. (How ever, Euler and Lagrange never met.) In 1766 Euler moved to St. Peters burg, Russia (where Catherine II was also bidding for scientific talent—it was the royal fashion to do so during the Age of Reason). At the recommendation of Euler and D’Alembert [289], the young Lagrange, aged forty, was ap pointed head of the Berlin Academy. As Frederick II put it, rather vaingloriously, the “greatest king in Europe” ought to have the “greatest mathematician in Europe” at his court. Lagrange applied his mathematical ability to a systematization of mechanics, which had begun with Galileo [166]. His interest in the subject was aroused when he read Wallis’s [198] treatise on the subject. Using the calculus of variations, he worked out very general equations from which all problems in mechanics could be solved. He summarized his methods in his book Analytical Me chanics, published in Paris in 1788 by a most reluctant publisher. The book was purely algebraic or, to use the term of Vieta [153], analytic, as the title pro claimed. There was not one geometric diagram in it. In astronomy Lagrange addressed him self to a general problem left open by Newton [231]. (Lagrange once said that Newton was the luckiest man in the his tory of the world, for the system of the universe could only be worked out once and Newton had done it; however, in this he was too pessimistic, for there was to be room for Einstein [1064] a century and a half later, and Lagrange himself proceeded to make significant additions to the knowledge of the universe.) Newton’s law of universal gravitation could deal with two bodies if they were alone in the universe, but the solar sys tem consists of many bodies. To be sure, the sun’s influence is supreme, but the minor bodies affect each other in minor ways called “perturbations” and these could not be ignored. Lagrange worked out mathematical treatments of the motions of systems containing more than two bodies, such as the earth-moon-sun system and the sys tem of Jupiter and its four moons. He included a study of situations in which three bodies might form a stable configuration as at the apices of an equi lateral triangle (provided one body was very small). Such a system (now called a “Trojan system”), including the sun, Jupiter, and certain asteroids, was actu ally discovered a century and a half later.
Lagrange thought there might be two kinds of perturbations, periodic and sec ular. The periodic type causes a planet’s orbit to vary first in one direction, then in the opposing direction, leading to no permanent change in the long run. The secular type caused an accumulating variation in one direction only so that the orbit is completely disrupted eventu ally. Lagrange tackled the problem of determining whether any of the observed perturbations in the solar system were indeed secular. In this he was joined by his younger contemporary Laplace [347], and together they answered, “No!” After Frederick the Great’s death, La grange moved to Paris in 1787 at the in vitation of Louis XVI and was there lionized by Marie Antoinette, though he had then entered a period of deep depression that made the final decades of his life largely unproductive. With the coming of the French Revolution it might have been better for Lagrange to depart, in view of his friendship with the royal family. He remained, however, and lived through the Terror, partly because of the general respect for his accom plishments and partly because of his for eign birth. The revolution gave him the opportu nity for one last service to science. He was appointed in 1793 to head a com mission to draw up a new system of weights and measures. Laplace and La voisier [334] were among the other members. Out of the deliberations of
[318] COULOMB
GUYTON DE MORVEAU [319] that commission came, in 1795, the met ric system, the most logical system of measurement ever devised. It is now the universal language of scientists, although (to our shame, be it said) the United States, almost alone, clings to the illogi cal English system of measurement in daily life. Napoleon delighted to honor Lagrange in the evening of his life and eventually made him a senator and a count. [318] COULOMB, Charles Augustin (koo-lome') French physicist
June 14, 1736 Died: Paris, August 23, 1806 Coulomb was a military engineer in his younger days, serving in the West Indies for nine years beginning in 1764. There, he supervised the building of fortifications in Martinique. He returned to Paris in 1776, with his health im paired, and his search for a quieter life drew him toward scientific experi mentation. When the disturbances of the French Revolution began he combined discretion with inclination and retired to the provincial town of Blois to work in peace. He rode out the Terror handily and was eventually restored to those posts he had lost, by an appreciative Na poleon. By then he had made his name. In 1777 he invented a torsion balance that measured the quantity of a force by the amount of twist it produced in a thin, stiff fiber. Weight is a measure of the force of gravity upon an object, so a tor sion balance can be used to measure weight. A similar instrument had been invented earlier by Michell [294], but Coulomb’s discovery was independent and in 1781 he was elected to the French Academy. Coulomb put the delicacy of his in strument at the service of electrical ex periments. In a course of experi mentation that began out of a desire to improve the mariner’s compass, he placed a small electrically charged sphere at different distances from another small electrically charged sphere and measured the force of attraction or repulsion (de pending on whether the charges were op posite or similar) by the amount of twist produced on his torsion balance. In this way he was able to show in 1785 that the force of electrical attraction or repul sion is proportional to the product of the charges on each sphere and inversely proportional to the square of the distance between the spheres, center to center. (Priestley [312] had come to this conclu sion a few years earlier on the basis of indirect evidence.) This meant that elec trical forces obeyed a rule similar to that of gravitational forces as worked out by Newton [231]. This is still called Cou lomb’s law. In his honor, an accepted unit for quantity of electric charge is the coulomb.
Cavendish [307] had actually discov ered Coulomb’s law before Coulomb, but Cavendish never published his results, and they were not discovered until half a century after his death.
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