Ragnarok : the age of fire and gravel

14 THE DRIFT.

and bowlders are all found mixed together in the utmost confusion, “higgledy-piggledy, pell-mell.”

Says Geikie :

“ Neither can till owe its origin to icebergs. If it had been distributed over the sea-bottom, it would assuredly haye shown some kind of arrangement. When an iceberg drops its rubbish, it stands to reason that the heayier blocks will reach the bottom first, then the smaller stones, and lastly the finer ingredients. There is no such assortment visible, however, in the normal ‘till” but large and small stones are scattered pretty equally through the clay, which, moreover, is quite unstratified.” *

This fact alone disposes of the iceberg theory as an explanation of the Drift.

Again : whenever deposits are dropped in the sea, they fall uniformly and cover the surface below with a regular sheet, conforming to the inequalities of the ground, no thicker in one place than another. But in the Drift this is not the case. The deposit is thicker in the valleys and thinner on the hills, sometimes absent altogether on the higher elevations.

“The true bowlder-clay is spread out over the region under consideration as a somewhat widely extended and uniform sheet, yet it may be said to fill up all small valleys and depressions, and to be thin or absent on ridges or rising grounds.” ¢

That is to say, it fell asa snow-storm falls, driven by high winds; or as a semi-fluid mass might be supposed to fall, draining down from the elevations and filling up the hollows.

Again: the same difficulty presents itself which we found in the case of “the waves of transplantation.” Where did the material of the Drift come from? On what sea-shore, in what river-beds, was this incaleulable mass of clay, gravel, and stones found ?

* “The Great Ice Age,” p. 72. + “American Cyclopedia,” vol. vi, p. 112.