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[301] TITIUS SPALLANZANI [302] 1775, perhaps the greatest single sea voyage ever made, Cook took his ship throughout southern waters down to the Antarctic circle and proved the nonexis tence of any vast southern continent other than Australia, or rather proved that any that did exist had to be confined to the Antarctic regions. This expedition outlined the southern hemisphere, except for Antarctica itself, in approximately the form in which it is now known to exist. Except for the polar regions the oceans of the earth had been entirely opened. It was on this voyage, too, that Cook tested the dietary theories of Lind [288] and found them to be sound. He re ceived a medal from the Royal Society for this. In his third and last voyage, from 1776 to 1779, he was commissioned to explore the far northern Pacific. He sailed the full north-south length of the ocean, discovering the Hawaiian Islands on the way. After following the Alaskan and Siberian coasts as far as the ice would permit, he returned to Hawaii. There, after one of the ship’s boats was stolen by the natives, a scuffle took place in which he was killed, and at the spot today an obelisk stands in his memory. Since the natives practiced cannibalism he was presumably eaten. For his last voyage, which took place during the American Revolutionary War, Benjamin Franklin [272], who fully appreciated the scientific importance of Cook’s work, arranged that he should not be molested by American privateers. [301] TITIUS, Johann Daniel (tish'us) German astronomer Born: Konitz, Prussia (now Choj- nice, Poland), January 2, 1729 Died: Wittenberg, Saxony, Decem ber 16, 1796 Titius, the son of a draper who was also a city councillor, was brought up by his uncle after his father’s death. His uncle, a naturalist, encouraged the youngster’s interest in science. He ob tained his master’s degree from the Uni versity of Leipzig in 1752. In 1756, he was appointed to a professorial position at the University of Wittenberg, where he remained for the rest of his life. The one thing for which he is remem bered in the history of science is his sug gestion in 1766 that the mean distances of the planets from the sun very nearly fit a simple relationship of A = 4 + (2n X 3), where the value of n is, suc cessively, — oo, 0, 1, 2, 3 and so on. This works out to the series: 4, 7, 10, 16, 28, 52, 100, . . . which fits the rela tive distance of Mercury, Venus, earth, Mars, --------- , Jupiter and Saturn. The dash between Mars and Jupiter was not filled by any planet. The relationship was not noted when first advanced and only came to the at tention of astronomers generally when Bode [344] publicized it in 1772. And then it was called Bode’s law, with poor Titius ignored. It turned out, how ever, that once Neptune was discovered seven decades later the “law” was only a coincidence with no actual scientific significance. Nevertheless, it did encour age Olbers [372] and others to search for the planetary objects in the empty spot and to discover the asteroids. [302] SPALLANZANI, Lazzaro (spahl- lahn-tsah'nee) Italian biologist
ary 12, 1729 Died: Pavia, Lombardy, February 11, 1799 Spallanzani, the son of a successful lawyer, attended the University of Bo logna, where his cousin, Laura Bassi, was a singular anomaly for that time—a woman professor of physics who man aged to have twelve children in her spare time. It is thought she influenced him in the choice of a scientific career. He obtained his Ph.D. in 1754 and then became a priest in order to help support himself. He taught at several Italian universities, visited Naples in 1788 while Vesuvius was in eruption, and, unlike Pliny [61], survived. He had made trips along the shores of the Medi terranean and even into Turkey in 1785 197 [302] SPALLANZANI BOUGAINVILLE
to collect natural history specimens for the museum at Pavia, where Maria Theresa of Austria had placed him in charge. His most dramatic work is in connec tion with the question of spontaneous generation. By the eighteenth century the matter of the spontaneous generation of animals visible to the naked eye was a closed one. Thanks mainly to the experi ments of Redi [211] a century before, even insects were known to arise only from eggs. But regarding the microor ganisms discovered by Leeuwenhoek [221] at about the time of Redi’s experi ments, the question remained open. Needham [285] had conducted experi ments that seemed to show microor ganisms did appear through spontaneous generation. Spallanzani tackled the prob lem in 1768, determined to be thorough. He not only boiled solutions that would ordinarily breed microorganisms, he boiled them for between one half and three quarters of an hour. Then he sealed the flasks. No microorganisms ap peared in the solutions however long they stood. His conclusion was that mi croorganisms appeared in such solutions only because they already existed in it in spore form, or were on the inner walls of the flask or in the air within the flask. Some of these organisms were resistant to brief boiling, but all succumbed to prolonged boiling. Spallanzani believed his own procedure killed all the microor ganisms in the solution, in the air above it or on the inner walls about it. Sealing the flask prevented new spores from en tering. The fact that no microorganisms appeared in such flasks meant that there was no spontaneous generation. This made possible Appert’s [359] advance in food preservations. But the battle was not over. Those who favored spontaneous generation maintained that by long boiling, Spallan zani had destroyed some “vital principle” in the air and that without this principle microorganisms could not breed. It was another century before that objection was finally taken care of by Pasteur [642].
At the request of his friend Bonnet [291], Spallanzani studied the mechanics of the development of eggs. He showed in 1779 that sperm cells had to make ac tual contact with egg cells if fertilization was to take place. He also carried through artificial insemination on a dog in 1785. In the last decade of his life Spallan zani grew interested in the problem of how nocturnal animals found their way. Bats flew easily in the most complete darkness. He blinded some bats and found them still capable of flying with perfect ease. Some days later he caught several and dissected them. Their stom achs were crammed with insect remains. Not only could they fly while blinded, but also they could catch insects. In his usual thorough manner he tackled the other senses (for he could not believe that the ability was what we would today call “extrasensory”). He found that when he plugged the bats’ ears, they were helpless. He had no explanation for this and the experiment seemed so bizarre—could an animal see with its ears?—that it was forgotten. It was only with developing knowledge of ultrasonic sound vibrations a century and more later that an answer to the problem became possible. [303] BOUGAINVILLE, Louis Antoine de (boo-gan-veelO French navigator
Bougainville was the son of a notary and, to avoid becoming a notary himself, he enlisted in the French army. He fought in North America as an aide-de camp to General Louis Joseph de Mont calm in the battles that lost French Can ada to the British. After the war was over in 1763, Bougainville joined the navy and led an expedition to the Falk land Islands off the shore of southern Argentina, but failed to establish a col ony in that rather forbidding territory. He was commissioned by the French government to set sail on a voyage of ex ploration and with this end in mind, he sailed in December 1766. The voyage took him around the world, and he led 198 [304] MÜLLER
MESSIER [305] the first French ships to accomplish the feat. He lost only seven men to scurvy, even though he did not have Cook’s [300] preventive of lime juice. He almost reached Australia but turned north too soon to sight its shores. He did sail along the Solomon Islands, the largest of which is Bougainville Is land, named in his honor since, in 1768, he was the first European to sight it. He confirmed the existence of marsupials in the eastern islands of Indonesia, some thing Buffon [277] had refused to be lieve. His voyage and those of Captain Cook finally completed the geography of the Pacific Ocean. After the voyage he became secretary to Louis XV, and then fought against the British in the course of the American Revolutionary War. Despite his royalist connections, he managed to avoid the guillotine in the French Revolution, and lived to be honored as a senator and count by Napoleon Bonaparte. [304] MÜLLER, Otto Friedrich Danish biologist
1784
Müller, the son of a court trumpeter, studied theology and law at the Univer sity of Copenhagen, then served an aris tocratic family for twenty years as tutor. In 1773 he married a wealthy widow, re tired, and devoted his remaining years to science. Müller was one of the early micros- copists and concentrated on the tiny bacteria first dimly seen by Leeuwenhoek [ 221
], These were at just about the limits of resolution of the primitive microscopes that antedated the modern achromatic varieties introduced by J. J. Lister [445], and Müller was the first who saw them well enough to divide them into catego ries. He introduced the terms “bacillum” and “spirillum” to describe two of the categories. He was also the first to classify mi croorganisms, generally, into genera and species after the fashion of Linnaeus [276].
[305] MESSIER, Charles (meh-syayO French astronomer Born: Badonviller, Meurthe-et- Moselle, Vosges, June 26, 1730 Died: Paris, April 11, 1817 Messier, the tenth of twelve children, was left fatherless when he was eleven. He went to work as an assistant to Delisle [255] in 1755 and became an ac complished astronomical observer. Messier was the first in France to spy Halley’s comet on the famous 1758 re turn that Halley [238] had predicted. This inspired him to become a comet hunter and his greatest pleasure was to track down those fuzzy creatures at their first appearance. Louis XV referred to him, with patronizing affection, as “my little comet ferret.” In his systematic searchings, however, he was constantly being fooled by fuzzy nebulosities that occurred here and there as permanent heavenly objects. In 1781 he made a compilation of a little over a hundred such objects in order that neither he nor any other comet hunter would be fooled by them. If a suspected comet were to be spotted, its position would first be checked against Messier’s list before being announced as a discovery. The objects in Messier’s list are still frequently known as Messier 1, Messier 2, or just Ml, M2, and so on. They cover a wide variety of objects. Some are indeed nebulosities. Others are collec tions of stars that, to Messier’s weak telescope, showed up simply as blurs. Thus Messier 13, first noted by Halley in 1714, is a huge cluster of stars, perhaps a million of them, all told, that is now known as the Great Hercules Cluster be cause it occurs in the constellation Her cules. About a hundred such clusters exist in our galaxy and all were noted down by Messier. Herschel [321] re solved them into stars. It was these clus ters that were used by Shapley [1102] a century and a quarter after Messier’s time to demonstrate the true size of the Milky Way. 199 [306] INGENHOUSZ CAVENDISH
In addition, some of Messier’s listed objects are systems of stars as large as or larger than the entire Milky Way. Thus, Messier 31 is the great Andromeda gal axy, which, a century and a half later, Hubble [1136] was to resolve, at least partly, into stars. As a comet hunter Messier was as good as could be expected, discovering twenty-one, but none of the comets he discovered are of any particular interest. The miscellany of objects he recorded in order to clear the way for his comets, however, have immortalized his name. He could not have predicted this, for in his time the true grandeur of the uni verse was unknown, though some, like Lambert [299] and Kant [293], were be ginning to suspect a bit of the truth. [306] INGENHOUSZ, Jan (ing'en- hows)
Dutch physician and plant physiologist Born: Breda, December 8, 1730 Died: Bo wood Park, Wiltshire, England, September 7, 1799 Ingenhousz, the son of a leather mer chant, got his medical training at the universities of Louvain and Leiden, re ceiving his medical degree in 1752. He traveled to England in 1764, where he eventually grew expert in the technique of smallpox inoculation. He went on to Vienna to inoculate the royal house and to become personal physician to Empress Maria Theresa in 1772. In 1779 he re turned to England and became a member of the Royal Society. In that year he published experiments clarifying the previous work of Hales [249] and Priestley [312]. He showed that green plants take up carbon dioxide and give off oxygen, but only in the light (hence “photosynthesis”—formation in light—is the name we now give the pro cess). In the dark, they, like animals, give off carbon dioxide and absorb oxy gen. This was the first indication of the role of sunlight in the life activities of green plants. Ingenhousz had thus dem onstrated the broad scheme of balance in nature. Plants, in the presence of light, consume the carbon dioxide produced by animals, and give off the oxygen that is in turn consumed by animals. The activ ity of both plants and animals brought about a balance in which oxygen and carbon dioxide were, in the long run, neither used up nor overproduced. It remained to fill in the details of these processes, of course, and those de tails after over a century and a half are only now falling into place. [307] CAVENDISH, Henry English chemist and physicist
1731
Died: London, February 24, 1810 Cavendish, of an aristocratic English family, was bom in Nice because his mother was there on a trip to improve her health in the salubrious climate of the Riviera. In this she did not succeed, and died when her son was two. Cavendish was educated in England and eventually spent four years at Cam bridge, but he never took his degree, partly because he would not participate in the obligatory religious exercises. He also seems to have thought he could not face the professors during the necessary examinations. In all his life, he had difficulty facing people. Mad scientists are many in fiction, few in real life. Yet certainly Cavendish comes as near to qualifying as any one of the truly first-class scientists of his tory. He was excessively shy and absent- minded. He almost never spoke and when he did it was with a sort of stam mer. He might, in an emergency, ex change a few words with one man, but never with more than one man, and never with a woman. He feared women to the point where he could not bear to look at one. He communicated with his female servants by notes (to order din ner, for instance) and any of these fe male servants who accidentally crossed his path in his house was fired on the spot. He built a separate entrance to his house so he could come and leave alone, and his library in London was four miles
[307] CAVENDISH CAVENDISH
from his house, so that people who had to use it would not trouble him. In the end he even literally insisted on dying alone. This eccentric had one and only one love, and that was scientific research. He spent almost sixty years in exclusive preoccupation with it. It was a pure love, too, for he did not care whether his findings were published, whether he got credit, or anything beyond the fact that he was sating his own curiosity. He wrote no books and published only twenty articles altogether. As a result, much of what he did remained unknown until years after his death. His experiments on electricity in the early 1770s anticipated most of what was to be discovered in the next half century, but he published virtually none of it. It was only a century afterward that Maxwell [692] went through Cav endish’s notes and published his work. There is no way of estimating what that unnecessary secrecy cost the human race in scientific progress. His electrical ex periments also proved his superhuman devotion to science. He had no talent for inventing instruments and he measured the strength of a current in a very direct way, shocking himself with the current or the charge and estimating the pain. Nevertheless he managed to live to be nearly eighty. Fortunately he suffered few economic pressures. He came of a noble family that included the dukes of Devonshire and he had a comfortable allowance. At the age of forty he inherited a fortune of over a million pounds but paid no partic ular attention to it; he continued living as before. On his death, the fortune, vir tually untouched, went to relatives, and his unpublished notes remained a rich mine for later scientists. In 1766 he communicated some early researches to the Royal Society, describ ing his work with an inflammable gas produced by the action of acids on metals. This gas had been worked with before—for instance, by Boyle [212], who had collected some, and by Hales [249]—but Cavendish was the first to in vestigate its properties systematically and he is usually given the credit for its dis covery. Twenty years later the gas was named hydrogen by Lavoisier [334]. Cavendish was the first to measure the weight of particular volumes of different gases to determine the density. He found hydrogen unusually light, with only one- fourteenth the density of air. The lightness of the gas and its easy inflam mability led him to believe he had actu ally isolated the phlogiston postulated by Stahl [241], a view quickly adopted by another well-known phlogistonist, Scheele [329]. On January 15, 1784, he was able to demonstrate that hydrogen, on burning, produced water. In this way water was shown to be a combination of two gases and if the Greek notion of the elements still required a deathblow, this was it. As was fashionable at the time, Cav endish experimented with air. In 1785 he passed electric sparks through air, forcing the nitrogen to combine with the oxygen (to use modem terminology) and dissolving the resulting oxide in water. (In doing so, he worked out the composition of nitric acid.) He added more oxygen, expecting to use up all the nitrogen in time. However, a small bub ble of gas, amounting to less than 1 per cent of the whole, remained uncombined no matter what he did. He speculated that air contained a small quantity of a gas, then, that was very inert and resis tant to reaction. As a matter of fact, he had discovered the gas we now call argon. This experiment was ignored for a century, however, until Ramsay [832] repeated it and followed it up. Cavendish’s most spectacular experi ment involved the vast globe of the earth itself. The law of gravitation as worked out by Newton [231] placed the mass of the earth in the equation representing the attraction between the earth and any other body (say, a falling object). How ever, the mass of the earth could not be calculated from the mass of the falling object, its rate of fall, and its distance from the earth’s center because the equation also contained G, the gravita tional constant, of which the value was not known. If the value of the gravitational con stant were known, then all the quantities
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