Biographical encyclopedia
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96 [160] ALPINI
LIBAVIUS [162] arithms introduced almost at once by Briggs [164]. Napier tried to mechanize the use of logarithms by the manipulation of calcu lating rods. These were called “Napier’s bones” and achieved a certain fame but were completely outclassed and replaced by a much more practical device first constructed by Oughtred [172]. Lost in the colossal structure of log arithms is another advance made by Napier, much smaller, almost invisible in fact but familiar to every grammar school student. Napier completed the present form of the decimal fraction, first used by Stevinus [158], by inventing the decimal point. [160] ALPINI, Prospero (ahl-pee'nee) Italian botanist Born: Marostica, Venice, Novem ber 23, 1553 Died: Padua, November 23, 1616 Alpini earned his medical degree at the University of Padua in 1578. He served as physician to the Venetian con sul in Cairo, Egypt. There he was able to study the date palm and to detect, for the first time, that plants, like animals, could exist as male and female. It was the sexual differences among plants that Linnaeus [276], a century and a half later, was to use as the basis for his classification of the plant kingdom. Alpini was also the first European to describe the coffee plant and the banana. In 1593 he became professor of botany at the University of Padua. He died of a kidney infection con tracted while in Egypt. [161] NORMAN, Robert English navigator Born: Bristol, about 1560 Died: date unknown Norman, a navigator, would naturally be interested in the compass and its workings. He was the first to note that steel did not alter its weight when it was magnetized. This argued against magne tism being a fluid which was somehow poured into the steel. He was also the first, apparently, who allowed a compass needle to swing up and down, showing, in 1576, that its north-seeking end would then point below the horizon. This is “magnetic dip” and was used to good effect by Nor man’s contemporary, Gilbert [155]. [162] LIBAVIUS (lih-bay'vee-us) German alchemist
1616
Libavius is the Latinized name of An dreas Libau, the son of a weaver, who is known almost entirely for the book he wrote. Like Zosimus [67], his contri bution to science is that he summarizes an epoch of alchemy. Libavius obtained his medical degree at the University of Jena in 1581 and was then town physician at Rothenburg from 1591 to 1596. After quarreling with the rector at Jena, where he was lecturing, he founded a school of his own in Coburg in 1605, remaining there till his death. In 1597 Libavius published Alchemia, a summary of the medieval achievements of alchemy that could be considered the first chemical textbook worthy of the name. He was a follower of Paracelsus [131] in that he believed in the impor tance of the medical applications of al chemy.
He differed from Paracelsus, however, in largely eschewing mysticism. He bit terly attacked the mumbo-jumbo of those he called Paracelsians and also argued against the doctrines of the Rosi- crucians. In fact, his writing is quite clear. He was the first to describe the preparation of hydrochloric acid, tin tet rachloride, and ammonium sulfate. He gave clear directions for preparing strong acids such as sulfuric acid and aqua regia. He suggested that mineral sub stances could be identified from the shape of the crystals produced when a solution is evaporated. More clearly than Paracelsus a half 97 [163] BACON
BACON [163] century earlier, Libavius foreshadowed the chemistry of the future. And yet, for all the foreshadowing, Libavius remained firmly immersed in al chemy. He believed in the possibility of transmutation and considered the discov ery of practical methods of making gold to be an important end of alchemical study.
[163] BACON, Francis English philosopher Born: London, January 22, 1561 Died: London, April 9, 1626 Bacon was born of a family prominent at the English court, and he himself took up the court as a career. He was a great success as a courtier, for he had a re markable facility for choosing the win ning side and abandoning it just before it stopped winning. He studied law at Cambridge where he gained a distaste for Aristotle’s [29] phi losophy. He entered practice in 1576. After a stay in France with the English ambassador, he entered Parliament in 1584. He became confidential aide to the earl of Essex, Queen Elizabeth I’s favor ite, but carefully judged the moment when Essex fell out of favor. By 1601 he was one of the judges who tried and con victed Essex for treason, and with Essex executed, he remained in favor with Eliz abeth. Elizabeth died two years later, but Bacon, in ample time, had won the favor of her successor, and under James I his star rose higher than ever, especially since he courted the patronage of the duke of Buckingham, James’s favorite. Bacon was knighted in 1603, shortly after James’s accession, became solicitor general in 1607, attorney general in 1613, lord chancellor in 1618. In 1618, also, he was raised to the peerage, being made Baron Verulam. Throughout, he bought his preferment by a disgraceful display of obsequiousness to people in authority and an unprincipled willingness to do any dirty work that needed doing. In 1621 he was made viscount of St. Albans, and at that moment, at the height of his career, he was suddenly dashed down. He was accused of taking bribes in his capacity as judge, and the evidence was overwhelming. Bacon’s only defense was that the bribes, al though accepted, did not influence his judgment, and that he judged against the bribe-giver when that seemed the just thing to do. (It did not seem to occur to him that to accept a bribe and then cheat the briber was to be doubly dis honest. ) He was not punished severely, as he might have been, because the king inter vened to spare him the worst However, his political career was over. (There are enthusiasts who think Francis Bacon wrote Shakespeare’s plays, largely be cause Bacon was very educated and wrote, as a matter of course, in Latin, while Shakespeare was, apparently, poorly educated.) Despite his mean character, Bacon was an effective and influential philosopher. In early life he wrote to his uncle that he was taking “all knowledge to be my province,” something that in his day, could still reasonably be attempted. And he was the first, perhaps, to see history as the story of developing ideas rather than of conquering kings. Bacon’s great contribution to experi mental science was the glow of respect ability he gave it. (He was no relation to Roger Bacon [99], however, who had at tempted the same thing three and a half centuries before.) In 1605 Francis Bacon published a book called Advancement of Learning in which he argued against mysticism and characterized the dead hand of tradition as the true devil threatening mankind. There was no use, he said, in studying magic and trying to work through spirits. Science should concern itself with the ac tual world that was apparent to the senses, for its true purpose was not that of bolstering religious faith, but of im proving the human condition. (Never theless, he accepted astrology, as indeed nearly everyone did up to the time of Newton [231].) In 1620 came the Novum Organum, that is, the “New Organon,” the refer ence being to the Organon of Aristotle in which the Greek philosopher had dem
[163] BACON
BRIGGS [164] onstrated the proper method of logic—of reasoning by deduction. Bacon’s book, as the title implies, contains a new method of reasoning. Bacon argued strenuously that deduc tion might do for mathematics but that it could not do for science. The laws of sci ence had to be induced, to be established as generalizations drawn out of a vast mass of specific observations. Bacon, however, was no experi mentalist himself and, ironically, one of his few attempts to be one brought on his death. In March 1626 he suddenly began to wonder if snow would delay the putrefaction of living tissue. (Substitute “cold” for “snow” and this is an excel lent stroke of intuition.) He was in his carriage at the time, staring at heaps of snow outside, and no doubt that set up the train of thought. He jumped out of the carriage, bought a chicken, and then, with his own hands, stuffed it with snow. He caught a chill almost at once, which turned to bronchitis and brought him to his death. Bacon’s concern with theory blinded him to the men who in his generation were practicing experimental science. Two of them, Gilbert [155] and Harvey [174], were in his own country and time. Moreover, his views remained (perhaps due to his intensively classical educa tion) medieval in some respects. For in stance, he could not bring himself to ac cept the views of Copernicus [127], for he could not swallow the notion of the great, solid earth flying through space. Harvey, unblinded by Bacon’s fine words, and seeing the backwardness of some of the thought, stated dryly that Bacon wrote of science “like a lord chancellor.” Nevertheless, Bacon put the theory of experimental science in the most refined of scholarly terms and made it possible for other scholars to accept it. The world of philosophy might easily ignore a Gil bert or even a Galileo [166] as a mere tinkerer and mechanic. (That is un doubtedly the way in which the Greek philosophers of the Alexandrian period viewed Hero [60], for instance.) But when Bacon placed the stamp of philo sophic approval on such “tinkering,” it became a different matter. Largely because of Bacon’s influence, experimental science became fashionable among English gentlemen. A group of them began to gather to discuss and practice the new intellectual fad, in imi tation of the “House of Solomon,” a community of investigators and philoso phers described by Bacon in his book
into the Royal Society, perhaps the most unusual collection of brilliant scientists to forgather in a single city since the great days of Alexandria. Yet Bacon had had a real-life model to draw on, too; for a similar group, “Accademia dei Lincei,” had been es tablished in Rome earlier by Porta [150]. Its membership had included Galileo. [164] BRIGGS, Henry English mathematician Born: Warley Wood, Yorkshire, February 1561 Died: Oxford, January 26, 1630 Briggs obtained his master’s degree in Cambridge in 1585 and lectured there in 1592. In 1596, he became professor of geometry at Gresham College in Lon don. He is remembered chiefly for his re action to Napier’s [159] publication of logarithms. He was lost in admiration for the beauty of the system and its sim plicity (and aghast at his own stupidity in not seeing it until it was shown him). He went to the considerable trouble of making a trip to Edinburgh to see Na pier and talk to him. Napier had written his exponential numbers as e2, e2-32, e 3.®7,
and so on, where e is an unend ing decimal fraction that starts 2.7182818284 . . . There are good mathematical reasons for doing this and such Napierian or “natural” logarithms are still used in calculus. However, Briggs pointed out during his conver sation with Napier the convenience of using exponential numbers such as 102, 102-32, 103-97, and so on. Log arithms in this fashion are called Briggs ian or “common” logarithms and are al 99 [165] SANCTORIUS GALILEO
most invariably used for ordinary calcu lations. Briggs worked out the first logarithm tables for numbers from 1 to 20,000 and from 90,000 to 100,000 (to fourteen places!) in 1624. Briggs also invented the modern method of long division. In 1619 he had reached the peak of his academic career when he became professor of astronomy at Oxford. Unlike Napier, Briggs scorned astrol ogy. [165] SANCTORIUS, Sanctorius (sank- toh'ree-us) Italian physician Born: Justinopolis, Venice (now Koper, Yugoslavia), March 29, 1561
Sanctorius obtained his medical degree at the University of Padua in 1582 and later is supposed to have spent fourteen years as physician to King Sigismund III of Poland and then to have returned to Italy. Along with Harvey [174], Sanctorius subjected the human body to its first quantitative measurements. As a profes sor of medicine at Padua, a post he took in 1611, he weighed human beings from day to day on a balance he had con structed himself and proved that they lost weight through “insensible perspi ration” (perspiration that evaporated as it formed). This marked the beginning of the modem study of metabolism. Galileo [166] had invented the first thermometer, a rather bulky and clumsy device in which a trapped volume of air changed the level of water in a tube as it expanded with a rise in temperature or contracted with a drop. Scantorius ap plied this device to measuring the warmth of the body by placing the bulb of air in the mouth. This was the first clinical thermometer. Sanctorius also in vented a device to measure the pulse rate.
Sanctorius, who never married, died of a disease of the urinary tract, one, no doubt, of the eighty thousand different diseases which, in a moment of mis guided theory, he at one time calculated were possible in human beings. [166] GALILEO (gahl-ih-lay'oh) Italian astronomer and physicist Born: Pisa, February 15, 1564 Died: Arcetri (near Florence), January 8, 1642 Galileo is universally known by his first name only, his full name being Galileo Galilei. The form of the name arose from a Tuscan habit of using a variation of the last name for the first name of the oldest son. He was bom three days before Michelangelo died; a kind of symbolic passing of the palm of learning from the fine arts to science. Galileo was destined by his father, a mathematician of a onetime wealthy but now rather run-down family, to the study of medicine and was deliberately kept away from mathematics. In those days (and perhaps in these) a physician earned thirty times a mathematician’s salary. Galileo would undoubtedly have made a good physician, as he might also have made a good artist or musician, for he was a true Renaissance man, with many talents. However, fate took its own turning and the elder Galilei might as well have saved himself the trouble. The young student, through accident, happened to hear a lecture on geometry and then, pursuing the subject further, came upon the works of Archimedes [47]. He promptly talked his reluctant father into letting him study mathematics and sci ence. This was fortunate for the world, for Galileo’s career was a major turning point in science. He was not content merely to observe; he searched for a cru cial experiment that would demonstrate his theories. He began to measure, to re duce things to quantity, to see if he could not derive some mathematical rela tionship that would describe a phenome non with simplicity and generality. He was not the first to do this, for it had been done even by Archimedes (whom
[166] GALILEO
GALILEO [166] Galileo extravagantly admired) eighteen centuries before. What’s more, Galileo was not really a thoroughgoing experi menter compared with those who were to follow, and he still retained a great deal of the Greek tendency to theorize. Nevertheless, Galileo made experi mentation attractive. For one thing, he had the literary ability (another talent) to describe his experiments and theories so clearly and beautifully that he made his quantitative method famous and fashionable. The first of his startling discoveries took place in 1581, when he was a teen ager studying medicine at the University of Pisa. Attending services at the cathe dral of Pisa, he found himself watching a swinging chandelier, which air currents shifted now in wide arcs, now in small ones. To Galileo’s quantitative mind, it seemed that the time of swing was the same, regardless of the amplitude. He tested this by his pulsebeat. Then, upon returning home, he set up two pendu lums of equal length and swung one in larger, one in smaller sweeps. They kept together and he found he was correct. (In later experiments, Galileo was to find that the difficulty of accurately mea suring small intervals of time was his greatest problem. He had to continue using his pulse, or to use the rate at which water trickled through a small orifice and accumulated in a receiver. It is ironic then, that after Galileo’s death Huygens [215] was to use the principle of the pendulum, discovered by Galileo, as the means by which to regulate a clock, thus solving the problem Galileo himself could not. Galileo also attempted to measure temperature, devising a ther moscope for the purpose in 1593. This was a gas thermometer which measured temperature by the expansion and con traction of gas. It was grossly inaccurate and not until the time of Amontons [244] a century later was a reasonable beginning made in thermometry. (It should never be forgotten that the rate of advance of science depends a great deal on advances in techniques of mea surement.) In 1586 Galileo published a small booklet on the design of a hydrostatic balance he had invented and this first brought him to the attention of the scholarly world. Galileo began to study the behavior of falling bodies. Virtually all scholars still followed the belief of Aristotle [29] that the rate of fall was proportional to the weight of the body. This, Galileo showed, was a conclusion erroneously drawn from the fact that air resistance slowed the fall of light objects that offered comparatively large areas to the air. (Leaves, feathers, and snowflakes are examples.) Objects that were heavy enough and compact enough to reduce the effect of air resistance to a quantity small enough to be neglected, fell at the same rate. Galileo conjectured that in a vacuum all objects would fall at the same rate. (A good vacuum could not be produced in his day, but when it finally was, Galileo was proved to be right.) Legend has it that Galileo demon strated his views by simultaneously drop ping two cannon balls, one ten times heavier than the other, from the Leaning Tower of Pisa. Both were seen and heard to strike the ground simultaneously. This seems to be nothing more than a legend, but a similar experiment was actually performed, or at least described, some years earlier by Stevinus [158], Nevertheless, the experiments that Galileo did indeed perform were quite sufficient to upset Aristotelian physics. Since his methods for measuring time weren’t accurate enough to follow the rate of motion of a body in free fall, he “diluted” gravity by allowing a body to roll down an inclined plane. By making the slope of the inclined plane a gentle one, he could slow the motion as much as he wished. It was then quite easy to show that the rate of fall of a body was quite independent of its weight. He was also able to show that a body moved along an inclined plane at a con stantly accelerating velocity; that is, it moved more and more quickly. Leo nardo da Vinci [122] had noted this a century earlier but had kept it to him self.
This settled an important philosophic point. Aristotle had held that in order to keep a body moving, a force had to be
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