There only remains now to notice the post-Tertiary deposits to complete this account of the geology of Maidstone. The surface-soil and the earth filling in and covering over the faults and large fissures consist of clay, gravel, “sharp” drift-sand, and fine sand, all being sedimentary deposits from water under different rates of motion. The exteriors of the highest masses of rock show the effects of a powerful erosion continued for a long period of time; but this action was not the dashing of billows, for some surfaces of the rock, although worn to a great extent, have portions of fragile shells standing out from their surfaces, just as in the cavernous gutters of the rock masses of spiculæ jut out from the walls, the loose sand or soft hassock having been washed away.