Morlot, the Swiss archæologist and naturalist, who has written a great deal upon the subject of the lacustrine settlements, was the first to endeavour to estimate the duration of the Stone Age, as well as that of the Bronze Epoch, and the following is the way in which he set about it. In the neighbourhood of Villeneuve there is a cone or hillock formed of gravel and _alluvium_, slowly deposited there by the stream of the Tinière which falls at this spot into the lake of Geneva. This cone was cut in two, to lay down the railway which runs along the side of the lake. Its interior structure was thus laid bare, and appeared to be perfectly regular, a proof that it had been gradually formed during a long course of ages. There were three layers of vegetable earth placed at different depths between the deposits of _alluvium_, each of which double layers had in its turn formed the outer surface of the cone. The first layer was found at a depth of 3 feet 6 inches from the top, and was 4 to 6 inches thick. In it were found some relics of the Roman epoch. The second, situated 5 feet 3 inches lower, measured 6 inches in depth, and was recognised as belonging to the bronze age; it contained a pair of bronze pincers and some fragments of unglazed earthenware. The lower bed lay at a depth of 18 feet from the top, and varied in thickness from 6 to 7 inches. It contained some rough earthenware, charcoal, and animal bones, all pointing to the Stone Age, but to the latest times of that period. After having carefully examined these different beds and ascertained the regular structure of the cone, Morlot fancied that he could calculate approximately the age of each of them. He took for his base of operations two historical dates; that of the entrance of the Romans into Helvetia, fifty-eight years before Christ, and that of their decisive expulsion towards the end of the fifth century of the Christian era. By comparing these two dates, he came to the conclusion that the Roman layer was at the most eighteen and at the least thirteen centuries old. Then remarking that since that epoch the cone had increased 3 feet 6 inches, and always going upon the hypothesis that the increase was the same as in subsequent ages, he came to the conclusion that the bed corresponding with the bronze epoch was at least 2900 and at the most 4200 years old; and that the layer belonging to the Stone Age, forming the entire remainder of the cone, was from 4700 to 10,000 years old.