Egyptian Chronology. 463 



that the same festival might at one time occur in summer, at 

 another in winter; and again in spring, and in autumn. On 

 this account they do not insert the quarter of u day, in order 

 that the religious solemnities may retrograde.' 



Thus we find the earliest authorities citing two different 

 years, which are, as will be seen, reconciled by one of later date. 

 The first of these was such that it circulated throughout the 

 seasons, and is hence called ( vague ;' the second was supposed 

 to coincide with the course of the sun. A year of 365J days, 

 however, does not coincide with the tropical year, nor had the 

 true length of the latter been discovered by any people of remote 

 antiquity. The close coincidence that the Egyptians attained 

 to, cannot be considered as due to observations of the sun ; 

 for it is obvious, from various circumstances, that their astro- 

 nomy did not go this length, but arose from the return of the 

 heliacal rising of Sirius, which, as has been seen, during the 

 flourishing periods of the Egyptian kingdom, occurred at exact 

 intervals of 365 days. The same observation gave them ori- 

 ginally a year of 365 days, for the discovery of which but few 

 years would have been sufficient, and afterwards enabled them 

 to ascertain its error. 



How they reconciled these two species of years in their chro- 

 nology we learn from Strabo : ' The Thebans, particularly the 

 priests, are said to be astronomers and philosophers $ it is their 

 custom to reckon the days, not by the course of the moon, 

 but by that of the sun. They annually add five days to their 

 twelve months of thirty days each ; but since a certain fraction 

 of a day exceeds the complement of the whole year, they make 

 a period of such a number of years, that the exceeding frac- 

 tions may make up a year. ' 



Such a period would be equal to 1460 Julian or 1461 vague 

 years, and it formed the famous Sothic period of the Egyptians, 

 the Cynic cycle of the Greeks, and the Canicular of Latin 

 authors. It took its origin when the first day of the vague 

 Egyptian year coincided with the rising of Sirius, and closed 

 when the same coincidence again occurred. This coincidence 

 did occur, and the cycle terminated in the year 138 A.D. The 

 origin is, therefore, to be found in the year 1322 before our 

 era. Between these dates it was used as an ordinary mode of 



