INTRODUCTION.

B Y the present theory, the earth on whichwe dwell is represented as having beenformed originally in horizontal strata at thebottom of the ocean; hence it should appear,that the land, in having been raised from thesea, and thus placed upon a higher level,had been of a different shape and conditionfrom that in which we find it at the presenttime. This is a proposition now to be con-sidered.

In whatever order and disposition the hardand solid parts of the land were at the time ofits emerging from the surface of the sea, noprovision would have then been made for con-ducting the rivers of the earth ; therefore, thewater from the heavens, moving from thesummits of the land to the shores, must haveformed for themselves those beds or channelsin which the rivers run at present; bedswhich have successively changed their placesover immense extents of plains that have of-