

NEBULAE. 317 



confounded with their actual distribution through the regions 

 of space. We no\v, therefore, proceed to the consideratior 

 of the remarkable differences presented by their individual 



prima gente]. I am the more certain of this, because I 

 actually saw four stars, which together formed a lozenge, and 

 had a slight (?) movement." Vespucci refers to the Southern 

 Cross, la croce maravigliosa of Andrea Corsali (Letter from 

 Cochin, dated January 6, 1515, in Ramusio, vol. i, p. 177), 

 whose name he did not then know; but. which, subsequently 

 served to mark to all pilots the position of the South Pole 

 (as p and 7 Urs. Min. indicated the North Pole. (Mem. de 

 I'Acad. des Sciences, 1 666-1699, torn. vii. part 2. Paris, 1729, 

 p. 58.) This constellation also served for determinations of 

 latitude. (Pe*dro de Medina, Arte de Navegar, 1545, lib. v. 

 cap. xi. p. 204.) Compare my investigation of the celebrated 

 passage of Dante in the Examen crit. de I Hist, de la Geogr. 

 torn. iv. pp. 319-334. I there drew attention to the fact that 

 a of the Southern Cross, which was carefully observed in 

 modern times, by Dunlop (1826), and by Riimker (1836), 

 at Paramatta, is one of those stars whose multiple nature was 

 first recognized in 1681 and 1687 by the Jesuits Fontaney, 

 Noel, and Richaud. (Hist, de I'Acad. dep. 1686-1699, torn. li. 

 Par. 1733, p. 19; Mem. de I'Acad. dep. 1666-1699, torn. vii. 

 2, Par. 1729, p. 206; Lettres edijiantes, recueil vii. 1703, 

 p. 79.) This early recognition of binary systems, long before 

 that of Ursa3 Maj. (Cosmos, vol. iii. p. 252), is the more 

 remarkable, as Lacaille, seventy years later, did not describe 

 a Crucis as a double star ; perhaps (as Riimker conjectures), 

 because the main star and the companion were then not suffi- 

 ciently distant from each other. (Compare Sir John Herschel, 

 Observations at the Cape, 183-185.) Richaud also disco- 

 vered the binary character of a Centauri, almost simultaneously 

 with that of a Crucis, and fully nineteen years before the 

 voyage of Feuillee, to whom Henderson erroneously attributed 

 the discovery. Richaud remarks, " that at the time of the 

 Comet of 1689, the two stars which form the double star 

 a Crucis were at a considerable distance from each other; 

 but that in a twelve -feet refractor, both parts of a C^ntauri 



