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[ 1 2 2 ] LEONARDO DA VINCI VESPUCIUS [123]
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71 [ 1 2 2 ] LEONARDO DA VINCI VESPUCIUS
where the laws of nature were no longer observed.) The new picture of the globe that fol lowed on Columbus’ voyage seemed to emphasize the littleness and insufficiency of ancient knowledge. The fact that huge lands existed of which Aristotle [29] and Ptolemy [64] knew nothing, seemed to lift some of the psychological restraint of intellectual rebellion. The birthpangs of the imminent Scientific Revolution (Co pernicus [127] was nineteen when Co lumbus made his great voyage) were made that much easier. [122] LEONARDO DA VINCI (veen'- chee) Italian artist Born: Vinci, near Florence, April 15, 1452 Died: Castle Cloux, near Am- boise, France, May 2, 1519 Leonardo was of illegitimate birth, but was acknowledged and raised by his fa ther, a notary. Most of us think of him as an artist, particularly as the painter of the “Mona Lisa” and the “Last Supper,” but he was much more than that. Even more than Alberti [117] he was a “Re naissance man,” though he lacked a clas sical education and knew neither Latin nor Greek. He was a military engineer who visual ized devices beyond the scope of his time and drew sketches of primitive tanks and airplanes, using all sorts of elaborate gears, chains, ratchets, et cetera. He was endlessly ingenious in the mechanical gadgetry possible to the level of technol ogy of the time. He is supposed to have designed the first parachute and to have constructed the first elevator, one for the Milan cathedral. In order to design air planes he studied the flight of birds, and for submarine designs he studied the manner in which fish swam. He also ad vertised his abilities as flamboyantly as Alhazen [85] five centuries earlier, but more honestly and with better results. Despite the seeming bloodthirstiness of his war engines, he was a humanitarian who denied himself meat out of an aver sion to the killing of animals. Moreover, the combination of military engineering ability and superlative artis tic skill brought Leonardo a succession of powerful patrons in an age that val ued war and art equally. These included Lorenzo the Magnificent of Florence, Ludovico Sforza of Milan, Cesare Bor gia, the son of Pope Alexander VI, Louis XII of France, Giulio de Medici, brother of Pope Leo X, and, finally, Francis I of France.
In science Leonardo had amazing in sight. He had a notion of the principle of inertia, and nearly a century before Gali leo [166] he understood that falling bod ies accelerated as they fell. He grasped the impossibility of perpetual motion decades before Stevinus [158], As an artist, he studied the structure of the muscles and bones of the human body, dissecting some thirty cadavers. (This brought on some difficulties with authorities in Rome.) He also studied the structure and working of the heart and its valves and speculated on the cir culation of the blood a century before Harvey [174], He considered the moon to be earthy in nature and to shine by reflected sun light; and the earth not to be the center of the universe, and to be spinning on its own axis. He even considered the possi bility of long-continued changes in the structure of the earth two centuries ahead of Hutton [297] and had correct opinions as to the nature of fossils. His close observation and his amazing skill at drawing were such that his pictures of waves and bubbles in water could not be improved on till the coming of the slow motion camera. Unfortunately he kept his ideas to himself, writing them in code in volumi nous notebooks so that his contem poraries knew nothing of his ideas and remained uninfluenced by them. It is only we modems who have learned of them, and that only long after the fact. [123] VESPUCIUS, Americus (ves- pyoo'shus) Italian navigator Born: Florence, March 1454 Died: Seville, Spain, February 22, 1512
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DÜRER [126] Americus Vespucius is the Latinized version of Amerigo Vespucci. Vespucius was the son of a notary, who worked for Florentine bankers and was sent by them on missions to Spain. The voyages of Columbus [121] had shaken the world; Asia had presumably been reached, and yet the wealth and civilization of Asia had not become ap parent. Between 1497 and 1504, Vespu cius took part in voyages to the western shores of the Atlantic to consider the matter.
Vespucius did not make any funda mental physical discoveries, but he did something more important. He had a keen flash of insight. To his dying day, Columbus had been convinced he had reached Asia; but to Vespucius, this was impossible. The new lands extended too far to the south. In 1504, Vespucius said that the new lands were not Asia but represented a new continent totally un known to the ancients; and that between that continent and Asia there must stretch a second ocean. (Actually, Co lumbus, too, would have believed this, were it not that he was convinced earth was considerably smaller than it really was.) It was this concept which really marked the break with the ancient world. If Columbus had simply reached Asia, this was after all in accordance with the Greek notions of the world. It was a new continent unknown to them that turned everything topsy-turvy, and it is only justice that the new continents were named America after Vespucius and not Columbia after Columbus. Vespucius ended his life as official as tronomer to Ferdinand II of Spain. Ves pucius met Columbus toward the end of the latter’s life and their relationship was friendly. [124] CANO, Juan Sebastian del (kah'- noh)
Spanish navigator Bom: Guetaria, about 1460 Died: somewhere in the Pacific Ocean, August 4, 1526 The great moment of Cano’s life was his return to Spain with one ship carry ing a crew who had circumnavigated the earth. It is he, not Magellan [130], who deserves the title of first circum navigator. However, it was Magellan whose grit kept the expedition together during the terrible months in the Pacific. Cano died four years later on a second expedition to the far Pacific. The pitcher went to the well once too often. [125] WALDSEEMOLLER, Martin (vahlt'zay-myool-er) German cartographer Born: Radolfzell or Freiburg, Baden, about 1470 Died: St. Die, Alsace (now in France), about 1518 Were it not for one thing, Waldsee- miiller and his maps (competent though they were) would have sunk without a trace as far as the history books were concerned. In 1507, however, he printed one thousand copies of one particular map in which he decided that Columbus’ [121] discovery was indeed a new continent as Americus Vespucius [123] claimed it was, and in the excitement of his sudden conviction, he named that new continent “America” and inscribed the name on the map. It was the first time the name had ap peared in print on a map, and it caught on at once. All but one of the maps of that printing were lost with time. The ex ceptional one was uncovered in 1901 in the private library of a German noble man. Waldseemiiller was canon of St. Die at the time of his death. [126] DÜRER, Albrecht (dyoo'rer) German artist
Dürer, the son of a goldsmith, worked as his father’s apprentice in early life. He is pre-eminently known as one of the great artists of history. He was per
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haps the greatest to express himself in the field of engraving and woodcuts, and as the inventor of the art of etching. Like Leonardo da Vinci [122], Dtirer’s interest in art drove him to science. In 1525 he published a book on geometrical constructions, using the straightedge and compass. Essentially, it was for use by artists, for this was at the height of the move for naturalism in art, a time when artists strove to present a perfect three dimensional illusion on a two-dimen sional surface. It might, from this stand point, be considered the first surviving text on applied mathematics. However, Dürer was not content merely to supply artists with mathe matical recipes; he supplied careful proofs to show the validity of his con structions, which included complex curves. The book was published in Ger man (it was unusual in those days to publish learned material in the “vulgar tongue”), but it was quickly translated into Latin so that it might serve the needs of artists and scholars outside Ger many. Dürer also wrote on the propor tions of the human body. Dürer was court painter to Emperor Maximilian I and to his successor, Charles V. [127] COPERNICUS, Nicolas (co-peri- nuh-cus)
Polish astronomer Born: Torun, February 19, 1473 Died: Frombork, May 24, 1543 Copernicus was the son of a well-to-do copper merchant and, after his father’s early death in 1483, was brought up by his uncle, a prince-bishop, so he had the advantage of being able to get a first- class education. Beginning in 1491, he studied mathe matics and painting at Cracow, then and for many years afterward the intellectual center of Poland. In 1496 he traveled to Italy for a decade’s stay, during which time he studied medicine and canon law, and after reading the works of Regio montanus [119], interested himself in as tronomy.
In 1500 this interest wax intensified when he attended a conference in Rome that dealt with calendar reform, under stood to be necessary since the time of Roger Bacon [99] two centuries before but not to come for another seventy years. The intellectual ferment in Italy was not above questioning established ways. The system of the universe as pro pounded by Hipparchus [50] and Ptol emy [64], in which all heavenly bodies were considered rotating about the earth, was almost indecently complex and de spite all the careful mathematics in volved was not very useful for predicting the positions of the planets over long pe riods. The Alfonsine Tables, of Alfonso X [100], the best the previous centuries had produced, were already far off the mark, and the corrections of Regiomon tanus were only of temporary value. It occurred to Copernicus as early as 1507 that tables of planetary positions could be calculated more easily if it were assumed that the sun, rather than the earth, were the center of the universe. This would mean that the earth itself, along with the other planets, would have to be considered as moving through space and revolving about the sun. This was not a new idea. Among the ancients, Aristarchus [41] had suggested the notion, and not many years before the time of Copernicus, Nicholas of Cusa [115] had made a similar sugges tion. Copernicus was to do more than sug gest, however. Beginning in 1512, he set about working out the system in full mathematical detail in order to demon strate how planetary positions could be calculated on this new basis. In doing this, he made little use of his own obser vations, for astronomical observation was not his forte, apparently. He is sup posed never to have seen the planet Mer cury (which is, however, the most dif ficult of the planets to observe because of its nearness to the sun). Still, his ob servations were good enough to enable him to determine the length of the year to within twenty-eight seconds. As it turned out, the Copernican sys tem explained some of the puzzling mo tions of the planets rather neatly. The 74 [127] COPERNICUS COPERNICUS
orbits of Mercury and Venus, according to the new system, would naturally never take those planets farther than a certain distance from the sun, as viewed from the earth, because the orbits of those two planets lay closer to the sun than did the orbit of the earth. On the other hand, since the earth would have to be consid ered as traveling in a smaller orbit than those of Mars, Jupiter, and Saturn, it would periodically overtake those planets and cause them to appear to be moving backward in the sky. Both the limited motion of Mercury and Venus and the backward (“retro grade”) motions of Mars, Jupiter, and Saturn had been thorns in the side of the Ptolemaic theory and vast complications had been introduced to account for them. Now they were easily and simply explained. Furthermore, the phenome non of the precession of the equinoxes, discovered by Hipparchus, could be ex plained not by a twisting of the entire celestial sphere, but by a wobbling of the earth as it rotated on its axis. As for the celestial sphere of the stars, Copernicus held it to be a vast distance from the earth, at least a thousand times as distant as the sun, so that the positions of the stars did not reflect the motion of the earth. (The fact that they did not was used as an argument against Copernicus, an argument that was not fully laid to rest until the time of Bessel [439] three centuries later.) So much was explained so well by the new Copernican system that it grew tempting to consider that system as more than a mere device to calculate planetary positions. Perhaps it described the actual situation, moving earth and all. Coper nicus, however, still kept the notion of perfectly circular orbits and had to re tain thirty-four of the epicycles and ec centrics associated with the older theory. This was not corrected until the time of Kepler [169] a half century later. Copernicus described his system in a book, but for years he hesitated to pub lish it, believing that any suggestion that the earth moved would be considered heretical and might get him into trouble. This view was a natural and perhaps a prudent one in the light of the later trou bles of Galileo [166] and Bruno [157]. In 1505 Copernicus returned to Po land, where he served as canon, under his uncle, at the cathedral at Frombork (Frauenberg, in German), though he never became a priest. (He never mar ried, just the same.) He also served as his uncle’s doctor and fulfilled a variety of administrative duties, especially after his uncle’s death. He was involved in diplomatic negotiations between the Poles and the Teutonic Knights of Prus sia, for instance. Then, too, in working on currency reform, he came up with the notion that the appearance of debased currency drives good coins into hiding— something later called “Gresham’s law” after an economist who was a younger contemporary of Copernicus. Meanwhile, by 1530, he had prepared a summary of his notions in manuscript and this circulated among Europe’s scholars, creating considerable interest and enthusiasm. Finally, at the urging of the mathematician Rheticus [145], Co pernicus permitted publication of his en tire book, carefully dedicating it to Pope Paul III. Rheticus volunteered to oversee its publication. Unfortunately, Rheticus had to leave town since he was involved in some rather uncomfortable doctrinal disputes and since he had a chance to accept a better position at Leipzig. He left a Lutheran minister, Andreas Osiander, in charge. Luther had expressed himself firmly against the Copernican theory, and Osiander played it safe by adding an unauthorized preface to the effect that the Copernican theory was not advanced as a description of the actual facts but only as a device to facilitate computation of planetary tables. This weakened the book and for many years compromised Copernicus’ reputation, for it was long thought that he was responsible for the preface. It wasn’t until 1609 that Kepler discovered and published the truth. The book was published in 1543 and the story has long persisted that the first copy reached Copernicus as he lay on his deathbed, suffering from a stroke. A copy of the book, dated four weeks be fore his death has recently come to light 75 [128] BALBOA
SCHÖNER [129] and it may be that Copernicus had a chance to see it. Only a few hundred copies of this original edition were printed. About two hundred of them still exist, forty-four of them in various American collections. The Vatican Library, ironically enough, has three. The original hand-written draft also exists and we can see in it that Copernicus crossed out an original refer ence to Aristarchus (in order not to have some suppose, it may be, that his ideas were derivative). The book began to win converts at once, Reinhold [143] using it within a few years to publish new tables of plane tary motion. Nevertheless it was not a financial suc cess. It was overpriced and was allowed to go out of print. A second edition was not printed till 1566 (in Basel, Swit zerland) and a third not until 1617 (in Amsterdam). With Copernicus began the Scientific Revolution, which was to dethrone Greek science and set man on a new and far more fruitful path. It reached a cli max and fulfillment with Newton [231] a century and a half later. Yet it was not until 1835 that Copernicus’ book was re moved from the list of those banned by the Roman Catholic Church. In 1807 Napoleon’s conquering career had brought him to Poland. He visited the house in which Copernicus was born and expressed his surprise that no statue had been raised in his honor. In 1839 this omission was rectified, but when the statue to Copernicus was unveiled in Warsaw, no Catholic priest would officiate on the occasion. [128] BALBOA, Vasco Nünez de (bal- boh'uh)
Spanish explorer Born: Jerez de los Caballeros, Ba dajoz, 1475 Died: Panama, 1517 Balboa was a man for whom misfor tune seemed to be a constant companion. He was forever getting into debt and having to go to extremes to elude his creditors. He went to America in 1500 for a new start. In what is now Haiti, he tried to be a planter, went into debt as usual, man aged to get onto a ship by hiding in a large barrel that was supposed to be full of provisions, and ended up on the northern coast of South America. When conditions grew bad there, he suggested in 1510 that the colony be transferred to Darien (what is now Pan ama). There, in 1513, he received a let ter indicating he would be summoned back to Spain to answer certain charges. He decided that the charges would surely be dismissed if he could find gold. He outfitted an expedition of 190 Spanish soldiers and a thousand Indian warriors and headed inland from the Panama coast to find the gold. He didn’t realize he was on a narrow isthmus. On September 7, 1513, he found himself on the other side of the isthmus, facing what seemed to be a huge body of water. Since Panama runs east and west and the Atlantic was on the north shore; Balboa called this new body of water the South Sea. He didn’t quite realize it but for once he had had an amazing stroke of good fortune. He was the first European ever to see the eastern end of the Pacific Ocean. He was standing on the shore of the second ocean that Americus Vespu- cius [123] had talked of nine years be fore as lying between Europe and Asia. But the good fortune wasn’t enough; for it wasn’t gold. Balboa was replaced as head of the colony and eventually was falsely accused by his enemies, convicted on trumped up charges and perjured tes timony, and beheaded. [129] SCHÖNER, Johannes (shoi'ner) German geographer
Yugoslavia), January 16, 1477 Died: Nuremberg, Bavaria, January 16, 1547 Schöner studied theology in the Uni versity of Erfurt. He did not take a de gree but was ordained a Roman Catholic priest.
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