Page:Geology and Mineralogy considered with reference to Natural Theology, 1837, volume 1.djvu/46

 42 a power whose effect in melting the most solid materials of the earth we witness in the fusion of the hardest metals, and of the flinty materials of glass.

Beneath the whole series of stratified rocks that appear on the surface of the globe (see section Pl. 1), there probably exists a foundation of unstratified rocks; bearing an irregular surface, from the detritus of which the materials of stratified rocks have in great measure been derived, amounting, as we have stated, to a thickness of many miles. This is indeed but-a small depth, in comparison with the diameter of the globe; but small as it is, it affords certain evidence of a long series of changes and revolutions; affecting not only the mineral condition of the nascent surface of the earth, but attended also by important alterations in animal and vegetable life.

The detritus of the first dry lands, being drifted into the sea, and there spread out into extensive beds of mud an