[10] In a recent paper read to the Anthropological Society by Professor Prestwich, in Feb. 1892, he confirms the above statement, and says that 1452 specimens have now been found at heights of from 400 to 800 feet, and extending over an area of twenty miles in length; while similar implements have been found on the South Downs near Eastbourne 350 feet above the sea level; and at heights of 596 and 760 feet on the hills near Dunstable. He says, "Looking at the very distinctive features of those plateau implements, such as their rudeness of make, choice of material, depth of wear and staining, peculiarity of form--taken in conjunction with the extreme rarity of valley forms--they constitute characters so essentially different from those of the latter implements, that by these characters alone they might be attributed to a more primitive race of men; and as this view accords with the geological evidence, which shows that the drift-beds on the chalk plateau with implements are older than the valley drifts, I do not see how we are to avoid the conclusion, that not only was the plateau race not contemporary with the valley men, but also that the former belonged to a period considerably anterior to the latter--either an early glacial or a pre-glacial period." I will mention only one other instance, which shows that the New World confirms the conclusion as to the antiquity of the quaternary age. The auriferous gravels of California consist of an enormous mass of _débris_ washed down by pre-glacial or early glacial rivers from the western slopes of the great coast range. During their deposition they became interstratified with lavas and tuffs from eruptions of volcanoes long since extinct, and finally covered by an immense flow of basalts, which formed a gently inclined plane from the Sierra Nevada to the Pacific. This plane was attacked by the denudations of the existing river-courses, and cut down into a series of flat-topped hills, divided by steep cañons and by the valleys of the present great rivers. In one case, that of the Colombia river, this denudation has been carried down to a depth of over 2000 feet, and the river flows between precipitous cliffs of this height. The present gold-mining is carried on mainly by shafts and tunnels driven through superficial gravels and sheets of basalts and tuffs, to the gravels of the pre-glacial rivers, which are brought down in great masses by hydraulic jets. In a great number of these cases stone implements of undoubted human origin have been found at great depths under several successive sheets of basalts, tuffs, and gravels. Mr. Skertchly, an eminent English geologist, who recently visited the district, says of these gravels, "Whatever may be their absolute age from a geological standpoint, their immense antiquity historically is beyond question. The present great river system of the Sacramento,