Meteorology   

lapse of time has hidden the beginning of the process. However, all

the mouths of the Nile, with the single exception of that at

Canopus, are obviously artificial and not natural. And Egypt was

nothing more than what is called Thebes, as Homer, too, shows,

modern though he is in relation to such changes. For Thebes is the

place that he mentions; which implies that Memphis did not yet

exist, or at any rate was not as important as it is now. That this

should be so is natural, since the lower land came to be inhabited

later than that which lay higher. For the parts that lie nearer to the

place where the river is depositing the silt are necessarily marshy

for a longer time since the water always lies most in the newly formed

land. But in time this land changes its character, and in its turn

enjoys a period of prosperity. For these places dry up and come to

be in good condition while the places that were formerly well-tempered

some day grow excessively dry and deteriorate. This happened to the

land of Argos and Mycenae in Greece. In the time of the Trojan wars

the Argive land was marshy and could only support a small

population, whereas the land of Mycenae was in good condition (and for

this reason Mycenae was the superior). But now the opposite is the

case, for the reason we have mentioned: the land of Mycenae has become

completely dry and barren, while the Argive land that was formerly

barren owing to the water has now become fruitful. Now the same

process that has taken place in this small district must be supposed

to be going on over whole countries and on a large scale.

Men whose outlook is narrow suppose the cause of such events to be

change in the universe, in the sense of a coming to be of the world as

a whole. Hence they say that the sea being dried up and is growing

less, because this is observed to have happened in more places now

than formerly. But this is only partially true. It is true that many

places are now dry, that formerly were covered with water. But the

opposite is true too: for if they look they will find that there are

many places where the sea has invaded the land. But we must not