The characteristics of the drift.
Reader,—Let us reason together:—
What do we dwell on? The earth. What part of the earth? The latest formations, of course. We live upon the top of a mighty series of stratified rocks, laid down in the water of ancient seas and lakes, during incalculable ages, said, by geologists, to be from ten to twenty miles in thickness.
Think of that! Rock piled over rock, from the primeval granite upward, to a height four times greater than our highest mountains, and every rock stratified like the leaves of a book; and every leaf containing the records of an intensely interesting history, illustrated with engravings, in the shape of fossils, of all forms of life, from the primordial cell up to the bones of man and his implements.
But it is not with the pages of this sublime volume
we have to deal in this book. It is with a vastly different but equally wonderful formation.
Upon the top of the last of this series of stratified
rocks we find
What is it?
Go out with me where yonder men are digging a well. Let us observe the material they are casting out.
First they penetrate through a few inches or a foot or two of surface soil; then they enter a vast deposit of sand, gravel, and clay. It may be fifty, one hundred, five hundred, eight hundred feet, before they reach the stratified rocks on which this drift rests. It covers whole continents. It is our earth. It makes the basis of our soils; our railroads cut their way through it; our carriages drive over it; our cities are built upon it; our crops are derived from it; the water we drink percolates through it; on it we live, love, marry, raise children, think, dream, and die; and in the bosom of it we will be buried.
Where did it come from?
That is what I propose to discuss with you in this work,—if you will have the patience to follow me.
So far as possible, [as I shall in all cases speak by the voices of others] I shall summon my witnesses that you may cross-examine them. I shall try, to the best of my ability, to buttress every opinion with adequate proofs. If I do not convince, I hope at least to interest you.
And to begin: let us understand what the Drift is, before we proceed to discuss its origin.
In the first place, it is mainly unstratified; its lower formation is altogether so. There may be clearly defined strata here and there in it, but they are such as a tempest might make, working in a dust-heap: picking up a patch here and laying it upon another there. But there
are no continuous layers reaching over any large extent of country.