sirius. 133 



gani, who invariably follows Ptolemy, should not here indi- 

 cate the change of color in so celebrated a star. Negative 

 proofs are, however, not often conclusive, and, indeed, El- 

 Fergani makes no reference in the same passage to the color 

 of Betelgeux (a Orionis), which is now red, as it was in the 

 age of Ptolemy. 



It has long been acknowledged that, of all the brightest 

 Luminous fixed stars of heaven, Sirius takes the first and most 

 important place, no less in a chronological point of view than 

 through its historical association with the earliest development 

 of human civilization in the valley of the Nile. The era of 

 Sothis — the heliacal rising of Sothis (Sirius) — on which Biot 

 has written an admirable treatise, indicates, according to the 

 most recent investigations of Lepsius,^ the complete arrange- 

 ments of the Egyptian calendar into those ancient epochs, in- 

 cluding nearly 3300 years before our era, " when not only the 

 summer solstice, and, consequently, the beginning of the rise 

 of the Nile, but also the heliacal rising of Sothis, fell on the 

 day of the first water-month (or the first Pachon)." I will 

 collect in a note the most recent, and hitherto unpublished, 

 etymological researches on Sothis or Sirius from the Coptic, 

 Zend, Sanscrit, and Greek, which may, perhaps, be accept- 

 able to those who, from love for the history of astronomy, seek 

 in languages and their affinities monuments of the earlier 

 conditions of knowledge.! 



* See Chronologie der JEgypter, by Richard Lepsius, bd. i., 1849, s. 

 190-195, 213. The complete arrangement of the Egyptian calendar is 

 referred to the earlier part of the year 3285 before our era, i. e., about 

 a century and a half after the building of the great pyramid of Cheops- 

 Chufu, and 940 years before the period generally assigned to the Deluge. 

 (Compare Cosmos, vol. ii., p. 114, 115, note.) In the calculations based 

 on the circumstance of Colonel Vyse having found that the inclination 

 of the narrow subterranean passage leading into the interior of the pyr- 

 amid very nearly corresponded to the angle 26° 15', which in the time 

 of Cheops (Chufu) was attained by the star a Draconis, which indicated 

 t»he pole, at its inferior culmination at Gizeh, the date of the building of 

 the pyramid is not assumed at 3430 B.C., as given in Cosmos according to 

 Letronne, but at 3970 B.C. (Outlines of Astr., § 319.) This difference 

 of 540 years tends to strengthen the assumption that a Drac. was re- 

 garded as the pole star, as in 3970 it was still at a distance of 3° 44' from 

 the pole. 



t I have extracted the following observations from letters addressed 

 to me by Professor Lepsius (February, 1850). "The Egyptian name 

 of Sirius is Sothis, designated as a female star ; hence rj 2w0ic is identi- 

 fied in Greek with the goddess Sote (more frequently Sit in hieroglyph- 

 ics), and in the temple of the great Ramses at Thebes with Isis-Sothis 

 (Lepsius, Chron. der JEgypter, bd. i., s. 119, 136). The signification of 

 the root is found in Coptic, and is allied with a numerous family of words, 



