All that we have hitherto described will explain the mean motions of the solar system, and the mean motions only. To account for all irregularities, Copernicus (hampered with the notion that all motions must be compounded of circular ones) is obliged to introduce a system of epicycles entirely resembling that of Ptolernmus. It will surprise many readers to hear that the greater part of the work of Copernicus is taken up with the description of this most essential branch of the real ' Copernican system.' But it must be added that the Copernican epicycles are more successful than the Ptolemaic. The latter were utterly unsufficieut as a means of demonstrating the chan;es of distance of the planets and earth. The former, founded upou a basis which brought this point not very far from the truth at the outset, made a much nearer approximation to a correct repre sentation of the inequalities. But as the epicyclio system is not now connected with the name of Copernicus, we need pursue this subject no further, satisfied that what we have done will have a teudeucy to put the reputation of that sagacious investigator in its proper place, and that uo mean one, though lower than the one usually assigued to it.
Of the tables of Copernicus, his trigonometrical formulm, &c., this is not the place to speak : they are mere connected with the sciences they belong to than with his biography.
While Copernicus was in daily expectation of receiving a complete copy of his work from Rheticus, he was seized with hemorrhage,. followed by paralysis. The book actually arrived May 23, 1543, and, as Gysius wrote to Rheticus, Copernicus saw it, and touched it, but was too near his end to do more. He died in a few hours after, and was buried in the cathedral to which he belonged.
We copy the following references to sources of information from the Bibliog. Astron.' of Lalande; p. 595; Adam, Vitm Phil. Germ. '• ' Tycho Brah6, do Math.;' Juvius, Elog. Met Vir.;' lialdus, Proleg. Astr. ; ' Vossius, `De Sci. Math. ; ' Crasso, 'Elog.d'Uom. Letter.;' Ghilini, 'Teatro,' tom. ii.; Freherus, torn. ii.; Blount, Cens. Cel. Auet.; ' Paschius, De Iuvent. Nov. Ant.;' Actu Phil.; part v., p. 884; Zernecke, Chronik von Thorn,' '2 ed., Berlin, 1727; Pautheou der Deutsehen; 1796; 'Berlin. Mouatsehrifft; August 1792, March 1793; 'Preussisches Archly.; December 1796; Wieland, • Teutscher Merkur,' November 1776. We may here notice that Ghiliui asserts an epistle De Motu Octavo) Sphmras ' to have been printed; but as Gassendi had never seen it, and we can find no mention of it, we conclude no such epistle was published, though one with the` name was certainly writt-'n.