We have already had occasion to remark that the earth's equatorial diameter exceeds the polar by about twenty-six miles.
Two facts are revealed by the oblateness of the earth: 1.

That she has formerly been in a yielding or plastic condition; 2.

That she has been modeled by a mechanical and therefore a secondary cause.
But this influence of mechanical causes is manifested not only in the exterior configuration of the globe of the earth as a spheroid of revolution, it also plainly appears on an examination of the arrangement of her substance.
If we consider the aqueous rocks, their aggregate is many miles in thickness; yet they undeniably have been of slow deposit.

The material of which they consist has been obtained by the disintegration of ancient lands; it has found its way into the water-courses, and by them been distributed anew.

Effects of this kind, taking place before our eyes, require a very considerable lapse of time to produce a well-marked result--a water deposit may in this manner measure in thickness a few inches in a century--what, then, shall we say as to the time consumed in the formation of deposits of many thousand yards?
The position of the coast-line of Egypt has been known for much more than two thousand years.