Consequently, in finding masses of gravel in the composition of our
land, we must conclude, that there had existed a former land, on which
there had been transacted certain operations of wind and water, similar
to those which are natural to the globe at present, and by which new
gravel is continually prepared, as well as old gravel consumed or
diminished by attrition upon our shores.
Sand is the material which enters, perhaps in greatest quantity, the
composition of our land. But sand, in general, is no other than small
fragments of hard and solid bodies, worn or rounded more or less by
attrition; consequently, the same natural history of the earth, which
is investigated from the masses of gravel, is also applicable to those
masses of sand which we find forming so large a portion of our present
land throughout all the earth[16].
[Note 16: Sand is a term that denotes no particular substance; although
by it is commonly meant a siliceous substance, as being by far the most
prevalent. Sand is one of the modifications, of size and shape, in a
hard body or solid substance, which may be infinitely diversified.
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