Meteorology By Aristotle

So it is clear, since there will be no end to time and the world is
eternal, that neither the Tanais nor the Nile has always been flowing,
but that the region whence they flow was once dry: for their effect
may be fulfilled, but time cannot. And this will be equally true of
all other rivers. But if rivers come into existence and perish and
the same parts of the earth were not always moist, the sea must needs
change correspondingly. And if the sea is always advancing in one
place and receding in another it is clear that the same parts of the
whole earth are not always either sea or land, but that all this changes
in course of time.

So we have explained that the same parts of the earth are not always
land or sea and why that is so: and also why some rivers are perennial
and others not.

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BOOK II

Part 1

Let us explain the nature of the sea and the reason why such a large
mass of water is salt and the way in which it originally came to be.

The old writers who invented theogonies say that the sea has springs,
for they want earth and sea to have foundations and roots of their
own. Presumably they thought that this view was grander and more impressive
as implying that our earth was an important part of the universe.
For they believed that the whole world had been built up round our
earth and for its sake, and that the earth was the most important
and primary part of it. Others, wiser in human knowledge, give an
account of its origin. At first, they say, the earth was surrounded
by moisture. Then the sun began to dry it up, part of it evaporated
and is the cause of winds and the turnings back of the sun and the
moon, while the remainder forms the sea. So the sea is being dried
up and is growing less, and will end by being some day entirely dried
up. Others say that the sea is a kind of sweat exuded by the earth
when the sun heats it, and that this explains its saltness: for all
sweat is salt. Others say that the saltness is due to the earth. Just
as water strained through ashes becomes salt, so the sea owes its
saltness to the admixture of earth with similar properties.