COPEKNICAN SYSTEM. 387 COPERNICUS. be described as being a growth to which lie was only one of many contributors. The merit of having first formed the general notion of the system seems to he due to Pythagoras ; Copernicus has the credit of having, after the lapse of centuries, again drawn the attention of philosophers to it, and of having greatly in- creased the probability of its truth by his cal- culations and arguments: for the rest, the glory of having matured the idea belongs to Kepler, Galileo, and Xewton, who, through the discovery of the law of gravitation, finally demonstrated its truth efi'ectualh'. ^Many who have been used to reverence the name of Copernicus in connec- tion with this system would be surprised to find, on perusing his work, Dc liciohitionibiis Orhiiim, how much of error, unsound reasoning, and happy conjecture combined to secure for him in all limes the association of the system with his name. Dc Rccolutionibus Orbium, dedicated to Pope Paul 111., consists of six books, in which Coper- nicus undertook to demonstrate his whole system. The character of the reasoning which then passed for demonstration must be borne in mind in judging of the author's procedure in establish- ing his various positions. It was then thought a sufficient demonstration of a phenomenon to make a supposition, on which its occurrence would be intelligible, without attempting to bring the supposition itself, by an induction of facts, within the truth of nature; many abstract propositions, too, which would now appear to be simply silly, were at that time universally admitted to be of great weight in scientific arguments. Illustrations of both of these peculiarities may be gleaned from the first of the six books of De Revoliitionihus. It contains the following propo- sitions: (1) That the universe is spherical. This is estal)lished by such arguments as that the sphere is the most perfect figure, etc. (2) That the earth is spherical, which flows from the same kind of considerations. (3) That the earth and sea make one globe. (4) That the motions of all the heavenly bodies must be uniform and circular, or compounded of luiiform and circular motions. Here, again, we meet with singular reasons. A simple body must move circularly, and nothing but circular motion could give periodicity to phenomena. (5) That, supposing the distance of the stars to be immense, there is no reason why the earth should not have a mo- tion round its axis as well as a motion in its orbit, (6) That the sphere of the stars is immensely distant, ( 7 and 8 ) The ancients were wrong in placing the earth at the centre of the universe. The argiunents under this head are as imaginarv as those which they were designed to refute. The falling of a body to the earth is deduced from the assumption that it is only given to wholes to move circidarly, Avhile it is of the nature of parts, separated from their wholes, to move in straight lines. That there must be a centrum nninrli. an entity not recognized by mod- ern science, is admitted, the question being as to its position. (0) It is possible for the earth to have several motions. (10) Copernicus establishes the order of the planets, and draws a diagram of the .system much as it is now represented. It may be observed that, following the old systems, such as the Ptolemaic, he lays down a sphere for the fixed stars. See Firmament. The most brilliant and valuable part of the De Itcculutiuiiibus is that in which he explained, for the first time, the variations of the seasons, the precession of the equinoxes, and the stations and retrogradations of the planets. In general, his explanations are right, and perfect as to the general nature of the causes of the ])hcu(imena. But Copernicus had neither mathematical nor mechanical knowledge sullicient to eiiabh' liiui tc^ exphiin more than the mean motions of llie solar system. To account for irregularities, he was. obliged to introduce a system of epicycles en- tirely resembling that of Ptolemy. (See Ptole- maic System.) This arose from the false no- tion of his time that all motions must be com- pounded of circular ones, with the application of which idea, and with the invention of convenient epicycles, the greater part of the De Revolulioiii- biis is occupied. It may further be ad<led, to rectif.y the vulgar notion regarding the relation of Copernicus to the system of the lieavens, that he had no answer to offer to the mechanical objections to his system. ^lost of them, indeed. ^^■ere such as could not possibly he met by the mechanical knowledge of the time. One of the commonest was that against the axial motion of the earth, that it was inconsistent with the fact of bodies falling to the points of the earth di- rectly beneath the points from which they are drojiped; for this he had no answer, nor could he have, the laws of motion being not yet dis- covered, COPERNICIA, ko'per-nlshl-a. See Carnau- BA Palm, COPER'NICUS (Latinized form of Kopper- nigk) . XiCHOL.s ( 1473-1543) . A celebrated Ger- man astronomer, born at Thorn, a Prussian town on the Vistula, at that time belonging to Poland. He was instructed in the Latin and Greek lan- guages at home: in 1491 he was sent to the Uni- vei-sity of Cracow, where he studied mathematics and other sciences. In 1405 he went to Italy and spent some years in the study of law, astronomy, and medicine, in Bologna and Padua. His nat- ural bent, however, was toward mathematics, the stiuly of which he pursued Avith passion through all its branches. Having become enamored of the study of astronomy, he projected a journey to Rome in his enthusiastic admiration of Regiomontanus, who resided there and was then the most illustrious of the astronomers. On his arrival, in 1.500. he was kindly received by Regiomontanus. Here his reputation, and the favor of his distinguished friend, led to his lieing chosen professor of mathe- matics, lie became doctor decretorum at Ferrara in 1.503, and in 1505 returned to his native country, where, having entered into holy orders, he obtained through his uncle, the Bishop of Ermeland, a canonrs- at Frauenburg, in the en- jo nent of which he passed the rest of his life. His working day, it is said, he divided into three parts — one devoted to the duties of his ofiice, another to giving medical advice gratuitously to the poor, and the third to study. Soon after his return to Prussia, he began, in his thirty-fifth year (1507), to apply his fund of observations and mathematical Icnowledge to correcting the system of astronomy which then prevailed. The result was hi* De Rcrohilioiibus Orliiiim, a brief account of which is given under CopERNiCAX System, He eojnpleted it in 1530, in Lis fifty-seventh year. Twelve years, however.
