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the time the ice began to accumulate, and higher than the corresponding point of the surface of the ice at every earlier stage. When 3,000 feet of ice had accumulated, and when this body of ice had caused its full measure of depression, the temperature over it must have been reduced at each point by an amount corresponding to the actual increase of elevation of the snow surface over the pre-existent land surface at that point. The force of the point here made is in no way lessened if the depression caused by the accumulation of the ice lags behind the accumulation itself. In so far as the sinking lags behind the loading, the temperature of the surface is reduced beyond the limits indicated. The principles here referred to will neither be reversed in their operation, nor rendered nugatory, by further accumulation of ice. So long as the ice thickens, it will remain true at all times that each point of the surface of the ice-field must be higher than the corresponding point at any earlier stage in the process of accumulation, isostasy alone being considered. The elevation of the ice surface (and this is the surface which determines the climate), will overbalance any depression of the land surface which the ice can cause by the disturbance of isostatic equilibrium. There is, therefore, not only no tendency to the amelioration of climate as the result of excessive snow accumulation, but there is a constant reduction of temperature. Whatever may have caused the dissolution of the Pleistocene ice-sheet, it was not the amelioration of climate resulting from the depression caused by the weight of the ice itself, under conditions of isostasy.

With this number, The Journal of Geology begins the publication of a series of articles on the geological surveys of the various states of the Union. These articles will be prepared, so far as practicable, by the official geologists of the several states. Their purpose is to publish to the geological world the present condition of geological work in the various regions with which they deal. They will indicate what has been done, and by whom. They will make known the various plans on which survey work has been prosecuted in the several states. They will