THE NILE 299
from the rigors of a Scythian winter, flock thither to pass the cold season. If then, in the country whence the Nile has its source, or in that through which it flows, there fell ever so little snow, it is absolutely im- possible that any of these circumstances could take place.
As for the writer who attributes the phenomenon to the ocean, his account is involved in such obscurity that it is impossible to disprove it by argument. For my part I know of no river called Ocean, and I think that Homer, or one of the earlier poets, invented the name, and introduced it into his poetry.
Perhaps, after censuring all the opinions that have been put forward on this obscure subject, one ought to propose some theory of one's own. I will therefore proceed to explain what I think to be the reason of the Nile's swelling in the summer-time. During the winter, the sun is driven out of his usual course by the storms, and removes to the upper parts of Libj^a. This is the whole secret in the fewest possible words ; for it stands to reason that the country to which the Sun-god approaches the nearest, and which he passes most directly over, will be scan test of water, and that there the streams which feed the rivers will shrink the most.
To explain, however, more at length, the case is this. The sun, in his passage across the upper parts of Libya, affects them in the following way. As the air in those regions is constantly clear, and the country warm through the absence of cold winds, the sun in his passage across them acts upon them exactly as he is wont to act elsewhere in summer, when his path is in the middle of heaven — that is, he attracts the water. After attracting it, he again repels it into the
