In the original MS. occurs a reference (struck out) to Aristarchus of Samos as holding the theory of the earth's motion. (Prowe: II, 507, note.) The finding of this passage proves that Copernicus had at least heard of Aristarchus, but his apparent indifference is the more strange since an account of his teaching occurs in the same book of Plutarch from which Copernicus learned about Philolaus. But the chief source of our knowledge about Aristarchus is through Archimedes, and the editio princeps of his works did not appear till 1544, a year after the death of Copernicus. C.R. Eastman in _Pop. Sci._ 68:325.] [Footnote 112: Delambre: _Astr. Mod._ pp. xi-xii.] [Footnote 113: As the earth moves, the position in the heavens of a fixed star seen from the earth should differ slightly from its position observed six months later when the earth is on the opposite side of its orbit. The distance to the fixed stars is so vast, however, that this final proof of the earth's motion was not attained till 1838 when Bessel (1784-1846) observed stellar parallax from Königsberg. Berry: 123-24.] [Footnote 114: _Commentariolus_ in Prowe: III, 202.] [Footnote 115: Holden in _Pop. Sci._, 117.] [Footnote 116: Delambre: _Astr. Mod._, p. xi.] [Footnote 117: Snyder: 165.] Copernicus was extremely reluctant to publish his book because of the misunderstandings and malicious attacks it would unquestionably arouse.[118] Possibly, too, he was thinking of the hostility already existing between himself and his Bishop, Dantiscus,[119] whom he did not wish to antagonize further. But his devoted pupil and friend, Rheticus, aided by Tiedeman Giese, Bishop of Culm and a lifelong friend, at length (1542) persuaded him.[120] So he entrusted the matter to Giese who passed it on to Rheticus, then connected with the University at Wittenberg as professor of mathematics.[121] Rheticus, securing leave of absence from Melancthon his superior, went to Nürnberg to supervise the printing.[122] This was done by Petrejus. Upon his return to Wittenberg, Rheticus left in charge Johann Schöner, a famous mathematician and astronomer, and Andreas Osiander, a Lutheran preacher interested in astronomy. The printed book[123] was placed in Copernicus's hands at Frauenburg on May 24th, 1543, as he lay dying of paralysis.[124] [Footnote 118: Copernicus: Dedication, 3.] [Footnote 119: Prowe: II, 362-7.] [Footnote 120: Ibid: II, 406.] [Footnote 121: Ibid: II, 501.] [Footnote 122: Ibid: II, 517-20.] [Footnote 123: Four other editions have since appeared; at Basel, 1566, Amsterdam 1617, Warsaw 1847, and Thorn 1873. For further details, see Prowe: II, 543-7, and Thorn edition pp. xii-xx. The edition cited in this study is the Thorn one of 1873.] [Footnote 124: Prowe: II, 553-4.]