COPERNICUS, Nicoas, was born at Thorn, in Prussia, on the 19th February 1473. Zernecke, in his Chronicle of Thorn, affirms that he was the son of a peasant serf, and that his name was Zopernick; but the commonly received opinion is, that he was descended from a family of distinction in that part of the Prussian territory; and, indeed, the circumstances of his education are incompatible with the supposition of his having been of servile origin. The first elements of learning he acquired in his paternal mansion, where he seems to have been initiated in the rudiments of Greek and Latin; and he then went to prosecute his studies at Cracow, where he applied himself to philosophy and medicine, and ultimately took the degree of doctor in the latter department of science. But having, from his earliest years, evinced a strong passion for the mathematics, he followed with avidity the lessons which he received, and soon signalized himself by uncommon proficiency therein. He also studied astronomy, and familiarized himself with the use of the instruments then employed in astronomical observations. At that time, Regiomontanus enjoyed the highest reputation as an astronomer; and so much was Copernicus dazzled with the lustre which this celebrated man had shed upon the science of which he was accounted so great a master, that the young enthusiast resolved to undertake a journey into

Italy for the purpose of visiting him; and, in order that he might profit to the utmost by his tour, he applied himself to painting and design, in which he made considerable progress. At the age of twenty-three he set out for Italy, and passed some time at Bologna, whore he attended the prelections of the astronomer DominicoMaria, and also made some astronomical observations. He then proceeded to Rome, where he was kindly received by Regiomontanus, and honoured with his friendship, as he had previously been with that of Professor Maria at Bologna. Here he was appointed to a chair of mathematics, which he filled with much distinction, continuing at the same time to extend both his knowledge and his reputation. But after some years he·returned to his native country, where he was most favourably received on account of his great acquirements, combined with the simplicity and amenity of his manners. At length he took up his residence at Frauenburg, where his uucle, Bishop of Warmia, procured him a canonry. But owing to the conflicting claims and unjust pretensions of others, this situation did not immediately afford him the leisure and tranquillity which it promised, and he was for some time involved in ungrateful disputes and vexatious contentions. His clear right, however, aided by his firmness and constancy, soon carried him through all his difficulties; and he afterwards enjoyed that peaceful calm alike congenial to his disposition, and favourable to the pursuit in which he had so zealously embarked. Having accomplished this object, he then divided his time into three portions, one of which he employed in assisting in the divine offices, another in dispensing medical advice gratuitously to the poor, and a third in the prosecution of his favourite studies. The house which he then occupied is still to be seen at Allenstein, with the perforations which he had made in the walls of his chamber in order to observe the passage of the stars across the meridian; and there are also shown the remains of a hydraulic machine, similar to that at Marly, which he had constructed for the purpose of raising the water of a rivulet for the supply of Frauenburg. But although he lived in a state of retirement and seclusion, devoted to his clerical duties and the pursuits of science, this did not prevent him from undertaking the administration of the temporalities of the bishopric, which was several times confided to him during vacancies of the see; a trust which required both probity and courage, and which he executed in a manner highly honourable to his character. He had, in fact, to defend the rights and privileges of the bishopric against the encroachments of the Teutonic knights, who were then very powerful; and this duty he discharged without being either dazzled by their authority or intimidated by their threats. We mention this, foreign as it may seem to the object of a notice like the present, in order to show that the spirit of study and contemplation was, in his character, united with firmness and constancy; qualities which are not less necessary than genius for attacking and subverting prejudices, hallowed, as it were, by the belief or the credulity of ages. ,

Copernicus had seen and conversed with the most celebrated astronomers of his own time. He knew the labours of the ancients, and he was also astonished at the complication of their systems, no less than the discordance and want of symmetry which these supposed in the arrangement of the universe. He therefore determined to reexamine all these systems, to study them comparatively, to distinguish in each whatever might seem most probable as well as natural, and to try whether it might not be possible to combine the whole in a single system, at once more symmetrical and more simple. Amidst the variety of hypotheses which thus engaged his attention, two forcibly struck his mind, and therefore deserve particular[7:7:309] attention ;—that of the Egyptians, who made Mercury and Venus revolve round the sun, but who nevertheless carried Mars, Jupiter, Saturn, and the Sun himself, round the earth ;—and that of Apollonius Pergaeus, who chose the sun as the common centre of all the planetary movements, but who made that luminary revolve round the earth like the moon; an arrangement which afterwards became the basis of the system of Tycho Brahe. The circumstance which particularly fixed the attention of Copernicus on these hypotheses was, that they represented admirably the limited excursions of Mars and Venus around the sun, and explained their movements, direct, stationary, and retrograde; an advantage, indeed, which the hypothesis of Apollonius extended even to the superior planets. Thus the astronomical systems were already to him only playthings of fancy. He had tried them by the test of expe-rimentand observation; he had found the conditions which it was necessary they should satisfy; and as he knew the means by which alone they were to be judged of, the most difficult part of his discovery was already made. On the other hand, he saw that the Pythagoreans had removed the earth from the centre of the world, and had there placed the sun; and hence it appeared to him that the system of Apollonius would become more simple and symmetrical by only changing this circumstance; namely, rendering the sun fixed in the centre, and making the earth to revolve around him. He had also perceived that Nicetas, Heraclides, and other philosophers, in placing the earth in the centre of the world, had ventured to give it a movement of rotation round its axis, in order to produce the phenomena of the rising and setting of the stars, and the alternations of day and night; nor could he fail to be even more forcibly struck with the bold conception of Philolaus, who, removing the earth from the centre of the world, had not only given it a movement of rotation round an axis, but also a movement of annual circulation or revolution round the sun; and although it might then appear difficult, and even absurd, to displace the earth from the centre, in order to make it a simple planet, nevertheless, as he observed that the astronomers had hitherto conceived themselves at liberty to imagine circles in the heavens to represent the celestial phenomena, he thought that he might in like manner be permitted to try if he could invent some other arrangement which would establish a more simple order in the movement of the heavenly bodies. And thus, taking in each system whatever was true, and rejecting whatever was false and complicated, he at length composed that admirable whole, which is now called, after him, the Copernican System, and which is, in reality, the true arrangement of the planetary movements, such as it has been established by evidence which can never be shaken.

About the year 1507 Copernicus began to digest the ideas of which we have here traced the gradual formation, and to write down his discoveries; but, as has been already observed, he did not confine himself to general appearances, nor remain satisfied with their accordance or conformity to the great law which he had thus detected. He felt that, to prove his system, it was necessary to enter into detail, and even to calculate particular phenomena, in order to deduce therefrom tables of all the celestial notions; and thus to afford the means of predicting them with all the simplicity and precision which the grandness of the conception itself, and the first trials which it had undergone, seemed equally to promise. This was the labour of his whole life. He set himself to make observations;^[1. In 1540, Tycho Brahe sent Olaus, one of his pupils, to measure at Frauenburg the height of the pole on the tower where Copernicus had made his observations. He also preserved with religious care the parallactic instrument, composed of two wooden rules, divided each into 1414 parts, which Copernicus had himself constructed for his own use. ] he collected and combined those which had been made by others; and, in particular, he studied to deduce from his theory those phenomena of the system of the world which had hitherto appeared the most complicated, such as the stations and retrogressions of the planets, and the precession of the equinoxes. Lastly, when he conceived that he had-accumulated sufficient observations and proofs, he undertook to expound the whole of his discoveries, in a work divided into six books, and entitled De Orbium Calestium Revolutionibus, in which he unfolds his ideas nearly in the order in which we have here endeavoured topresent them, and subjects the whole of astronomy to the dominion of a single principle or law. It appears that this work was completed about the year 1530, when Copernicus had attained the age of fifty-seven; and it certainly forms one of the proudest monuments of genius and sagacity, happily united with patient thinking and persevering research, which any age or country has produced. '

The fame of his discoveries had already been bruited abroad; the most celebrated astronomers became impatient to see them fully developed, and he was pressed to publish them to the world; but, resisting all importunities, he still deferred, correcting daily the data with which more exact observations furnished him, and adding whatever further reflection supplied: perhaps, also, he was afraid to endanger his peace, by submitting himself to the judgment of his contemporaries; and this apprehension was unhappily but too well founded. There is nothing so confident in itself, or so intolerant, as ignorance. Show the truth to men, and if the object interest them but little, they will perhaps pardon your doing so; but if you wish to root from their minds an opinion which they have long admitted without question, and believed without inquiry, be it a prejudice ever so groundless and untenable, the fact of their having constantly admitted it is of itself sufficient to offend their pride, perhaps even to arm their hostility, against him who may have proved himself more cautious or more sceptical than themselves. Of this we have a striking example in the case of Copernicus. Whilst the most distinguished men of learning and science, the only proper judges in such matters, ranged themselves on the side of the new discoveries, the common herd were discomposed by them, and attempted either to denounce them as extravagant, or to represent them as absurd and chimerical. Copernicus, in fact, was about to be publicly ridiculed in a comedy, as Socrates had been by Aristophanes; but the respectable character of this great man, perhaps also the silence which he had hitherto observed, preserved him from this insult, and he who had so unworthily attacked him became an object of general contempt. After this need we be astonished that Galileo and Descartes were persecuted, and that even Newton should have hesitated to give his great discoveries to the world? Nevertheless, Copernicus seems to have felt that, in delaying longer the publication of his researches, he would be leaving the field open to ignorance; and that the exposition of truths so evident, accompanied with proofs so numerous and palpable, would be the best means of refuting the charges which presumptuous ignorance had by anticipation brought against his opinions. Accordingly, he permitted his friends to publish his book, which he dedicated to Pope Paul III.; in order, as he says, that he might not be accused of seeking to shun the judgment of [7:7:310]enlightened men, and that the authority of his holiness, if he approved of the work, might protect him from the baleful tooth of calumny.

The work was printed at Nuremberg, under the superintendence of Rhetieus, one of the disciples of Copernicus. The impression had just been completed, and the first copy transmitted by Rhetieus to his great master and friend, when Copernicus, who had all his life enjoyed the most perfect health, was attacked with dysentery, followed almost immediately by a paralysis of the right side, which again was accompanied with loss of memory and an obscuration of the understanding. In this melancholy state he lingered for several days. On that of his death, and only a few hours before lie expired, the copy of his work sent by Rhetieus arrived, and was placed in his hands. He saw it, touched it, and seemed conscious what it was; but, after regarding it for an instant, relapsed into a state of insensibility, which soon terminated in death. He died on the 24th May 1543, at the age of seventy. His tomb, which is not distinguished from that of the other canons, was, in 1581, adorned with a Latin epitaph by Bishop Cromer, the Titus Livius of Poland; and in 1800 a small monument was erected in honour of the illustrious discoverer of the true system of the heavens. The first work in which the labours of Copernicus were formally announced, in contradistinction to the notions which had hitherto prevailed, was a letter published by Rheticus, and entitled Ad Clar. V. d. Schonerum de Libris Revolutionum erndi-tiss. viri et Mathematici excellentiss. Rev. Doctoris Nicoai Copernici Torunnaei, Canonici Warmiensis, per quemdam juvenem Mathematicae studiosum, Narratio prima, Dantzie, 1540, 4to; reprinted, with an eulogium, at Basil, 1541, 8vo. The works of Copernicus are, 1. De Revolutionibus Orbium Coelestium, libri VI. Nuremberg, 1543, small folio; reprinted at Basil in 1566, with the letter of Rheticus, and also included in the Astronomia Instaurata of Nicoas Muler, Amsterdam, 1617 and 1640, 4to; 2. A treatise on trigonometry, with tables of sines, entitled De Lateribus et Angulis Triangulorum, Nittemberg, 1542, 4to; 3. Theophylactici Scholastici Simocattoe Epistolae morales, rurales, et amatoriae, cum versione Latina. In 1521, Copernicus presented to the states of his provinces a work on money; and several manuscript treatises of his are still preserved in the library of the bishoprie of Warmia. His life has been written by Gassendi, and immediately follows that of Tycho Brahé.

Chronique de Thorn, Berlin, 1727; Lalande, Bibliographie Astronomique, p. 63; Annales des Voyages, tome i. p. 361; Biographie Universelle, v. Copernicus. (a.)