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Rh the only other agent that has affected the country on a great scale is glacier ice. All the lakes lie directly in the courses of the ancient glaciers. The basin of the Lake of Geneva is 950 French feet deep near its eastern end, and was scooped out by the great glacier of the Rhone, the ice of which, from data supplied by Charpentier, was, as it issued from the valley, 3,550 feet thick to the bottom of the lake. This great weight of ice ground out the hollow of the lake, which gradually shallows towards Geneva, where the glacier thinned and the grinding power was lessened. Where the same glacier abutted on the Jura, the ice-current was arrested, and it flowed to the N.E. and S.W.; and where the ice was thickest and heaviest above the Lake of Neuchatel, it ground out the hollow in which the lake lies.

The lakes of Thun and Brienz lie in the course of the great Aar glacier, those of Zug and the Four Cantons in that of Altorf, the Lake of Zurich lies in that of the Linth, the Lake of Constance in the course of the prodigious glacier of the Rhine Valleys, the numerous little rock-basin lakes near Ivrea in the line of the glacier of the Val d'Aosta, and those of Maggiore, Lugano, and Como, in the courses of the two gigantic glacier-areas that drained the mountains between Monte Rosa and the Sondrio.

The sizes of the lakes and their depths were then shown to be, in several cases, proportional to the magnitude of the glaciers that ground out the basins in which they lie, and the circumstance as to whether the pressure of ice was broadly diffused, or vertical as in narrow valleys.

Finally, it was shown that rock-basins holding lakes are always exceedingly numerous in and characteristic of all countries that have been extensively glaciated. Lakes are comparatively few in the southern half of North America, but immediately south and north of the great lakes and the St. Lawrence, the whole country is moutonnée and striated, and is also covered with a prodigious number of rock-basins holding water. The same is the case in the North of Scotland, the whole area of which has been moulded by ice; and east of the Scandinavian chain, in another intensely glaciated region, the country is covered by innumerable lakes.

M. Melleville, the Vice-President of the Société Académique of Laon, has published an account in the 'Revue Archéologique' of an object of human workmanship found in the lignites of that neighbourhood.

Starting on the basis that man was contemporaneous with the great carnivora and herbivora, and that objects of his workmanship are found with their bones, he goes on to make out that the beds containing them differ from the diluvium as much in the materials of which they are formed as in the fossils they contain, and that they are more ancient than it as they are everywhere covered by it. Those deposits belong to that geological age, which immediately preceded the present era; whilst it is admitted that the diluvium marks the commencement of the recent or historic period. The ultimate consequence he deduces from the published observations on this subject is, that there are two stone-ages—the first ante-historic, corresponding to the epoch of the formation of the lacustrine beds of the Somme, and characterized by large implements entirely of flints chipped but never ground; the other by far more finished and various products, indicating a more advanced art and established relations