EGYPTIAN SCIENCE 



dations began and coincided with the actual time of 

 inundation. The more precise fixing of new year's 

 day was accomplished through observation of the time 

 of the so-called heliacal rising of the dog-star, Sirius, 

 which bore the Egyptian name So this. It chances 

 that, as viewed from about the region of Heliopolis, 

 the sun at the time of the summer solstice occupies an 

 apparent position in the heavens close to the dog-star. 

 Now, as is well known, the Egyptians, seeing divinity 

 back of almost every phenomenon of nature, very nat- 

 urally paid particular reverence to so obviously in- 

 fluential a personage as the sun -god. In particular 

 they thought it fitting to do homage to him just as he 

 was starting out on his tour of Egypt in the morning; 

 and that they might know the precise moment of his 

 coming, the Egyptian astronomer 'priests, perched on 

 the hill-tops near their temples, were wont to scan the 

 eastern horizon with reference to some star which had 

 been observed to precede the solar luminary. Of 

 course the precession of the equinoxes, due to that 

 axial wobble in which our clumsy earth indulges, would 

 change the apparent position of the fixed stars in ref- 

 erence to the sun, so that the same star could not do 

 service as heliacal messenger indefinitely; but, on the 

 other hand, these changes are so slow that observa- 

 tions by many generations of astronomers would be 

 required to detect the shifting. It is believed by 

 Lockyer, though the evidence is not quite demonstra- 

 tive, that the astronomical observations of the Egyp- 

 tians date back to a period when Sothis, the dog-star, 

 was not in close association with the sun on the morn- 

 ing of the summer solstice. Yet, according to the cal- 



37 



