Page:A Treatise on Geology, volume 1.djvu/235

 CHAP. VI. are not coextensive, at least their calcareous portions: the upper or Portland limestone is the most limited and interrupted; the lower or Bath rocks are the most extensive and connected, but at the same time, perhaps, the most variable. These and other results will appear in the following comparative table, suited to the north and south of England.

If, comparing Britain with Europe, we view the oolitic system in gross, we shall find as the most general result, three considerable groups of rocks, viz.:—

and may consequently view the whole as a succession of argillaceous sediments widely disseminated in the sea,