In the Reader, 14th October, 1865, and afterwards more fully in my papers on the “Boulder-clay of Caithness,” and on the “ Transport of the Wastdale Crag Blocks,” 2 the following were shown from physical considerations to be necessary results, viz.:—

1. That were the ice of Greenland much thicker than it is at present, which it evidently was during the Glacial Epoch, it would not float in Davis Straits and Baffin's Bay, and consequently, would not break up into icebergs, but would move over upon the North American continent in one continuous mass, and pursue its course southwards, until it gradually melted away under the influence of the Sun's heat.