THE SXJRFACK OF THE Gf.OBE. Ill 



From this positive coincidence, at a period so remote, M. Fourier, 

 who has determined all these coincidences by great labour and new 

 calculations, concludes, that since the length of the year of Sirius was 

 so perfectly known to the Egyptians, they must have determined it by 

 observations made during a long series of years, and with much ex- 

 actness ; observations as remote as 2500 years before our era, and 

 could not have been made either much before or much after this inter- 

 val of time.* 



Certainly, this result would be very striking if the length of the 

 year of Sirius had been directly decided by observations made on 

 Sirius itself. But experimental astronomers affirm, that it is impossible 

 that the heliacal rising of a star could serve as the basis of these exact 

 observations on such a subject, particularly in a climate where the cir- 

 cumference of the horizon is always so much loaded with vapours, that, on 

 fine nights, stars of the second and third magnitude are never seen within 

 a few degrees of the edge of the horizon, and that the sun itself, at its 

 rising and setting is entirely obscured. \ They maintain, that if the 

 length of the year had not been discovered by some other means, they 

 would have been mistaken in one or two days. J They do not doubt 

 then that this duration of three hundred and sixty-five days and a quar- 

 ter is that of the tropical year, inaccurately determined by the observa 

 of the shadow, or by that of the point where the sun rose daUy, and 

 ignorantly identified with the heliacal year of Sirius ; so that it would 

 be mere chance which determined with so much accuracy the duration 

 of the latter for the epoch in question. § 



We shall also, perhaps, conclude, that men capable of such accurate 

 observations, and who made them for so long a period, would not have 

 assigned so much importance as to worship him ; for they would have 

 seen that the coincidence of his rising with the tropical year and the 

 inundation of the Nile are only temporary, and only took place in a 

 determinate latitude. In fact, according to the calculations of M. 

 Ideler, 2782 years before Christ, Sirius appeared in Upper Egypt, the 

 second day after the solstice; in 1322, the thirteenth; and in one 

 hundred and thirty-nine after Christ, the twenty-sixth. || 



* See the great work on Egypt. Antiq. Mem. v. 1, p. 803 ; the ingenious Me- 

 moir of M. Fourier, entitled ' Recherches sur les Sciences et le Gouvernment de 

 I'Egypte.' 



f These are the words of the late M. Nouet, astronomer to the expedition to 

 Egypt. See Volney's ' Recherches Nouvelles sur I'Histoire Ancienne,' v. iii. 



X Delambre Abreg^ d' Astronomic, p. 217, and in his note on the Paranatellons. 

 Hist, de I'Astr. du Moyen Age, p. 52. 



§ Delambre's Report on M. de Paravey's Memoir concerning the Sphere, in the 

 8th vol. of the New Annals of Voyages. 



II Ideler loc. cit. p. 38. 



