5. To establish the Plutonic theory, it is at least necessary to demonstrate that the granite, which all hold to be the under rock, is the unstratified Plutonic foundation of all stratified rock. Recent facts have demonstrated that the granite is a sedimentary rock, or rock deposited in water. This being admitted, although contradicting the teachings of all the older text books, some writers, among them is Steel, in order to harmonize the Plutonic theory with these stubborn facts, have assumed that the primitive granite, which by the theory must have been trap or lava, has all been worn away by disintegration of water and ice, or both; and again, by water deposited as we now find it. But what was a white-hot globe of lava doing, while water and ice were tearing and grinding its lower crust to powdered sand? We have secondary granite, but its structure is very different from primitive granite. Besides containing hard pebbles and boulders of other stone, it is friable, and easily disintegrated under exposure. It is a bad theory that is driven to such unheard-of suppositions for its support. Nothing is more evident, if the granite is the under rock, and sedimentary, as represented and known to be, than that the Plutonic theory is completely without foundation. 6. The modern theory of metamorphic rock, occasioned by internal heat, is also false. This theory maintains that the granite, slates, and marble existed so near to the great body of internal heat that they must have been metamorphosed. Facts demonstrate that these rocks, as a rule, were never in heat equal to 700 deg. Fahr. Such a heat will readily disintegrate any of these formations. Any one can demonstrate this by melting a little lead upon a piece of slate, marble, or granite. The furnace is found to be the best general test of the origin of rock. Lava, having been in a melted state, will not disintegrate up to the melting point, but, as a rule, will readily melt at the white heat. Granite, the slates, marble, and rock in general, of a sedimentary formation, will disintegrate at a comparatively low heat, but they will not melt, except with alkaloids, or flux, and then only at a very high degree of heat. This test shows all the primitive rock, including injected seams, to have been formed in the sea, with no heat to change their structure since. There are a few exceptions to the rule of disintegration, as clay rock.