Durham and Northumberland.

new alluvial matter, and with rivers, in theprogressive course of time, change the formsof rocks, of coasts, and valleys.

The ground of this theory appears to bemore generally supported than any other, andat once opens to the imagination a strikingand wonderful sublimity in the plans of nature*If we contemplate the slow, though pro-gressive revolution of systems, if we unite withthem the frequent and extraordinary effects ofvolcanic eruption, the mind is lost in its ideasof an original Creation, and calculates in vainto discover the embryo of Nature.

We can only depend however upon our ownpowers of judgment, and the additional meansof evidence which are furnished us, for thereconciliation of these theories to our indivi-dual suppositions.

It appears most probable that the differentstrata have been formed by the mutual co-operation (under various circumstances) of de-composition in the internal laboratory of natureand volcanic eruptions; that subterraneous firesforced a passage through the superincumbentstrata, and created a series of formations bythe lava, which, descending from the crater,or mouth of the volcano, formed into pyra-midical laminae: supposing these eruptions