Biographical encyclopedia
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226 [336] LAMARCK
LAMARCK [336] Lamarck took a long time finding him self. He was the eleventh child of a fam ily of impoverished aristocrats who rec ognized no honorable profession (assum ing that money had to be made some how) but the army and the church. Young Lamarck was marked for the church very much against his will. His father died in 1760, however, and that event left him free to turn soldier. He did well enough, fighting with some distinction in the Seven Years’ War, where he received an officer’s com mission for bravery. By 1766 illness, resulting from overrough horseplay, had forced his resignation and he resumed ci vilian life. He tried his hand at several occupations and finally went into medi cine, writing a couple of overambitious books. An interest in plant life had been stirred when he was stationed in the army on the Mediterranean coast. Even tually this interest led to a book on French flora in 1778, and, with help from Buffon [277], he found himself on the road of natural history. In 1781 he was appointed botanist to the king, which meant a salary and the chance of traveling; then, in 1793, he became pro fessor of invertebrate zoology at the Mu seum of Natural History in Paris. Here, at last, at the age of nearly fifty, he came into his own. Linnaeus [276] had left the inverte brates rather in a mess from the stand point of classification. It was as though, having expended unbelievable energy and pains on the vertebrates, he had grown tired and thrown a bunch of the most diverse creatures into a single pi geonhole and called them “worms.” Lamarck tackled the miscellany and began to make order out of them. He differentiated the eight-legged arachnids (spiders, ticks, mites, and scorpions) from the six-legged insects. He es tablished a reasonable category for the crustaceans (crabs, lobsters, and so on) and for the echinoderms (starfish, sea urchins, and so on). He summarized his findings in publications that appeared be tween 1801 and 1809 and finally pro duced a gigantic seven-volume work be tween 1815 and 1822 entitled Natural History of Invertebrates which founded modem invertebrate zoology. (It was Lamarck who first used the terms “ver tebrate” and “invertebrate.” He also pop ularized the word “biology.” More important in the memory of pos terity than the very real and fruitful la bors summarized in these volumes is a theory of evolution advanced in his book
1809. It is very difficult to classify living species without thinking in terms of evo lution. Linnaeus had refused to face the possibility, and Cuvier [396] avoided it by adopting Bonnet’s [291] catas- trophism. Erasmus Darwin [308] was an evolutionist a half century before La marck, but he was a minor figure and rather a dilettante. Lamarck was the first biologist of top rank to devise, boldly and straight forwardly, a scheme rationalizing the evolutionary development of life, and maintaining that the species were not fixed but that they changed and devel oped. Unfortunately the scheme was wrong. Organisms, Lamarck suggested, made much use of certain portions of then- body in the course of their life and un derused others. Those portions that were used, such as the webbed toes of water birds, developed accordingly, while the others, such as the eyes of moles, with ered. This development and withering were passed on to descendants. Lamarck used the recently discovered giraffe for his most often quoted exam ple of this. A primitive antelope, he said, fond of browsing on the leaves of trees would stretch its neck upward with all its might to get all the leaves it could. It would stretch out its tongue and legs as well. In the process, neck, tongue, and legs would become slightly longer than they would have been otherwise. These longer body parts would be passed on to the young and when these had grown to adulthood, they would have a longer neck, tongue, and legs to begin with, would stretch them more, pass on still longer ones to their young and so on. Little by little the antelope would turn into a giraffe. This is an example of the “inheritance of acquired characteristics.” 227 [337] VOLTA
VOLTA [337] The theory foundered on the rock of fact, however. In the first place, La marck visualized evolution as the prod uct of attempts by the animal to change. This might be imagined in the case of long necks since necks can be stretched voluntarily. But how would it work in the development of protective color ation? Surely a creature couldn’t try to become striped or splotched. Secondly there was no reason to think that ac quired characteristics could be inherited. In fact all available experimental evi dence pointed in the opposite direction, that acquired characteristics could not be inherited. Mistaken or not, Lamarck moved evo lutionary theory into the forefront of bi ological thinking and for this deserves full credit. However, in his lifetime (during which he married three times and had eight children) he was overshad owed by the greater renown of the nonevolutionist Cuvier and died blind, penniless, and largely unappreciated. Cu vier had taken a strong dislike to La marck, as a matter of fact, owing to Lamarck’s sarcastic references to Cu vier’s theories of catastrophism. Cuvier was powerful at the time and those he opposed simply did not do well. Lamarck’s reputation was not helped by the fact that he was a vociferous op ponent of Lavoisier’s [334] new chemis try. Then, thirty years after his death, when evolutionary views finally won out, it was Charles Darwin [554] with his su perior mechanism of evolution by natu ral selection who gained the fame. Every once in a while Lamarckism (that is, the inheritance of acquired characteristics) comes to the fore in one form or another. The most recent exam ple is that of Lysenko [1214] in the So viet Union. [337] VOLTA, Alessandro Giuseppe Antonio Anastasio, Count (vole'- tah) Italian physicist Born: Como, Lombardy, Febru ary 18, 1745 Died: Como, March 5, 1827 Volta was born into a noble family that had come down in the world. Most of his brothers and sisters (he was one of nine children) entered the church. Not so, young Alessandro. He was not an infant prodigy by any means. He did not talk until he was four and his family was convinced he was re tarded. By seven, however, when his fa ther died, he had caught up with other children and then began to forge ahead. When he was fourteen, he decided he wanted to be a physicist. Volta was interested in the phenome non of the age, electricity, that interest having been aroused by Priestley’s [312] history of the subject. He even wrote a long Latin poem (considered rather good) on the subject. In 1774 he was ap pointed professor of physics in the Como high school and the next year he in vented the electrophorus, describing it first in a letter to Priestley. This was a device consisting of one metal plate cov ered with ebonite and a second metal plate with an insulated handle. The ebonite-covered plate is rubbed and given a negative electric charge. If the plate with a handle is placed over it, a positive electric charge is attracted to the lower surface, a negative charge re pelled to the upper. The upper negative charge can be drawn off by grounding and the process repeated until a strong charge is built up in the plate with the handle. This sort of charge-accumulating machine replaced the Leyden jar and is the basis of the electrical condensers still used today. Volta’s fame spread as a result. In 1779 he received a professorial appoint ment at the University of Pavia, where he continued his work with electricity. He invented other gadgets involving static electricity and received the Copley medal of the Royal Society in 1791. He was elected to membership in the Soci ety. The major feat of his life involved not static electricity, but dynamic electricity —the electric current. He had followed the experiments of Galvani [320], who was a friend of his and who sent Volta copies of his papers on the subject. Volta took up the question of whether the 228 [337] VOLTA
PINEL [338] electric current resulting when muscle was in contact with two different metals arose from the tissue or from the metals. To check this he decided in 1794 to make use of the metals alone, without the tissue. He found at once that an elec tric current resulted and maintained that it therefore had nothing to do with life or tissue. This sparked a controversy be tween the two Italians with the German Humboldt [397], the chief of Galvani’s supporters, and the Frenchman Coulomb [318], the chief of Volta’s. The weight of evidence leaned more and more heavily toward Volta, and Galvani died embit tered. In 1800 Volta virtually clinched the victory by constructing devices that would produce a large flow of electricity. He used bowls of salt solution that were connected by means of arcs of metal dipping from one bowl into the next, one end of the arc being copper and the other tin or zinc. This produced a steady flow of electrical current. Since any group of similar objects working as a unit may be called a battery, Volta’s de vice was an “electric battery”—the first in history. Volta made matters more compact and less watery by using small round plates of copper and zinc, plus discs of card board moistened in salt solution. Starting with copper at the bottom, the discs, reading upward, were copper, zinc, card board, copper, zinc, cardboard, and so on. If a wire was attached to the top and bottom of this “Voltaic pile” an electric current would pass through it if the cir cuit was closed. Within a short time the voltaic cell was put to practical use by William Nicholson [361] and this led directly to the astonishing work of Davy [421], The invention of the battery lifted Volta’s fame to the peak. He was called to France by Napoleon in 1801 for a kind of “command performance” of his experiments. He received a stream of medals and decorations, including the Legion of Honor, and was even made a count and, in 1810, a senator of the kingdom of Lombardy. Throughout his life, though, Volta, like Laplace [347], had the ability to shift with the changing politics of the time and to remain in good odor with whatever governments were in power. After Napoleon fell and Austria became dominant in Italy once more, Volta con tinued to do well and to receive posts of honor. Volta received his greatest honor, however, at the hands of no potentate, but of his fellow scientists. The unit of electromotive force—the driving force that moves the electric current—is now called the “volt.” The energy of moving charged parti cles produced by modern atom-smashing machines is measured in electron-volts. A billion electron-volts is abbreviated “bev,” and when we speak of the partic ular atom-smasher called the bevatron, the “v” in the name stands for Volta. Volta was also the first, in 1778, to isolate the compound methane, a major constituent of natural gas. [338] PINEL, Philippe (pee-nelO French physician
1745
Died: Paris, October 26, 1826 Pinel took his doctor’s degree at the University of Toulouse in 1773, and went to Paris in 1778. He supported himself first by teaching mathematics and translating scientific books. Under the influence of Linnaeus [276] he classified diseases into species, genera, orders, and so on. The labor was useless, but he became interested in the problem of mental disease after a friend of his had gone violently mad. Until his time the insane in most cul tures were believed to be possessed of demons and were often treated with a certain reverence. While this may seem fine for the insane, it was not treatment. If they grew violent, the only remedy was to put them in chains. Hospitals for the insane were dreadful nightmares of howling, demented people, imprisoned and often subjected to the most brutal treatment. It was even a form of amusement for presumably sane 229 [339] GÄHN
MONGE [340] people to visit the hospitals for a look at the antics of the unfortunates. In 1791 Pinel published his views on “mental alienation,” referring to a mind alienated from its proper function (and even today, especially in connection with courtroom evidence, a psychiatrist is sometimes called an alienist). Pinel ad vocated considering them as people, sick in mind, to be treated with the same consideration as the sick in body; and he advocated talking to patients, rather than manhandling them. The French Revolution was in full swing then and it was the time for upset ting encrusted tradition. In 1793 Pinel was placed in charge of an insane asy lum and there he struck off the chains from the insane and began to adopt sys tematic studies. He was the first, for in stance, to keep well-documented case histories of mental ailments. His methods were slow to be accepted, but within half a century they were dom inant in medicine, reaching a climax with the work of Freud [865]. [339] GAHN, Johann Gottlieb Swedish mineralogist
August 19, 1745 Died: Falun, Kopparburg, December 8, 1818 Gahn was born in an iron-mining town and began life as a miner (a practi cal, if not very easy, introduction to mineralogy). He worked himself upward not only in science but in business as well, for he ended life owning and man aging mines. He also took part in Swedish politics, serving in the legisla ture for a time. He studied under Bergman [315] and became especially proficient in the use of the blowpipe, the convenient analytical tool that had been introduced by Cron- stedt [292]. It was Gahn who trained Berzelius [425] in this technique. Gahn’s proficiency in mineralogy is marked by the fact that a zinc aluminate mineral is still called gahnite, but his best-known achievement is the isolation of metallic manganese in 1774. He gets the credit as discoverer of the metal although his friend Scheele [329] had done much of the preliminary spadework. In collabo ration with Scheele, Gahn discovered about 1770 that phosphorus was an es sential component of bone. Gahn had a connection with American history: during the Revolutionary War, copper was needed by the young nation for sheathing ships, and it was one of his companies that filled the rush order. [340] MONGE, Gaspard (mohnzh) French mathematician
1746
Died: Paris, July 28, 1818 Monge, the son of a merchant, showed remarkable mathematical ability in his early years. At sixteen he made a large- scale plan of Beaune, using original methods that impressed a military officer, who hired him as a draftsman. Monge’s methods of using geometry to work out quickly constructional details that ordinarily required complicated and tedious arithmetical procedures was the foundation of what is called “descriptive geometry.” It was so important in con nection with fortress construction that for a couple of decades it was guarded as a military secret. With the French Revolution, Monge became increasingly involved in public affairs. He was on the committee that worked out the metric system. He founded the ficole Polytechnique and was its first director. He worked out fur ther details of descriptive geometry which showed how to describe a struc ture fully by plane projections from each of three directions and finally received permission to publish and teach his methods in 1795. He was a close friend of Napoleon Bonaparte and accompanied him on his campaign in Egypt in 1798, returning in 1801. Having supported both the revolu tion and Napoleon, he was appropriately rewarded. He was made president of the senate in 1806 and comte de Peluze in 1808. After the fall of Napoleon, he was deprived of all his honors by the new
[341] PIAZZI
PIAZZI [341] government of Louis XVIII and harassed in many ways. He did not long survive. In chemistry, Monge was the first to liquefy a substance that ordinarily oc curs as a gas. In 1784 he liquefied sulfur dioxide, the normal boiling point of which is —72.7°C. [341] PIAZZI, Giuseppe (pyah'tsee) Italian astronomer Bom: Ponte de Valtellina (now located in Switzerland), July 16, 1746
Piazzi was a Theatine monk and priest, having entered the order in 1764. He received his early training in philoso phy but later in life took up mathematics and astronomy. The government of Naples (then an independent kingdom), having decided to establish observatories in its two largest cities, Naples and Palermo, put Piazzi in charge in 1780. He traveled to the observatories in France and England as preparation and in England visited Herschel [321]. There he had the doubtful privilege of falling off the ladder at the side of Herschel’s great reflector and breaking his arm. Piazzi established his observatory at Palermo and by 1814 had mapped the position of 7,646 stars. He showed that the proper motions first detected by Hal ley [238] were the rule among stars and not the exception. He also discovered a dim star called 61 Cygni with an unusu ally rapid proper motion, a star that was to play an important role a genera tion later when Bessel [439] came to ob serve it. Piazzi’s chief accomplishment did not, however, involve the stars at all. After Herschel’s discovery of Uranus, the as tronomical world was abuzz with plans for the discovery of additional planets. Uranus was in the position predicted for it by a mathematical rule popularized by Bode [344] and therefore called Bode’s law. Following this same rule, astrono mers suspected a planet to be lying be tween the orbits of Mars and Jupiter. (Even Kepler [169] had commented on the unusual size of the gap between the orbits of those two planets.) A group of German astronomers, of whom the most distinguished was Olbers [372], made preparations for a thorough survey of the heavens to locate this planet, if it existed.
While preparations were under way, Piazzi, on January 1, 1801, in the course of his systematic observation of the stars, came across one in the constellation Taurus that changed its position over a period of several days between observa tions. He began to follow its course. It appeared to be a planet lying between Mars and Jupiter, since it moved more slowly than Mars and more quickly than Jupiter. He wrote about this to Bode, but before its orbit could be determined, Piazzi fell sick and when he returned to the telescope the object was too near the sun to be observed. At this point Gauss [415] worked out a new method for calculating an orbit from only three reasonably spaced obser vations. Piazzi’s observations were sufficient, the orbit was calculated, the planet relocated, and it proved indeed to lie between the orbits of Mars and Ju piter. The new heavenly object was named Ceres after the Roman goddess most closely associated with Sicily. How ever, the planet was so dim, considering its distance, that it had to be very tiny. Herschel estimated a diameter of two hundred miles, and the modem figure is 485 miles. In any case it scarcely seemed a respectable planet. The search for additional bodies took place therefore (since the German as tronomers were all prepared for it) and in the next few years three more planets were discovered, each even smaller than Ceres. They were named the asteroids (“starlike”), a name suggested by Her schel because they were too small to show as discs in the telescope but ap peared as starlike points of light. (Some have suspected that Herschel wanted to reserve planetary discoveries for himself and therefore moved to refuse the tiny new worlds the name of planet.) “As teroids” is, however, a poor name, for the bodies are not really starlike and the alternate names “planetoids” or “minor planets” are usually considered prefera
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