Principles of Geology

Three marble columns stand in a ruined Roman market at Pozzuoli, and halfway up each one, well above a man's head, the stone is drilled through with the burrows of marine molluscs. Charles Lyell put that engraving at the front of his book because it carries the whole argument: this ground sank beneath the Mediterranean and rose again in the time since Romans laid that floor, and it needed nothing more violent than time to do it.