SUBMARINE CONDITIONS APPEALED TO. 
535 
gists hastily concluded, that all accumulations of like external form, in the neigh- 
bourhood of which, scored and polished surfaces of hard rocks appear, are true 
glacial moraines. We utterly deny this inference, which would even compel us to 
believe in the former existence of glaciers in a greater number of low than lofty 
positions. We think, that with no other agents than those which are still exhibited 
as geological signs, many of the appearances which have been recently referred to 
glacial action may be satisfactorily accounted for. 
In regard to the theory which explains the advance of glaciers, it may be said, 
that all the authors who have written on that subject, refer the scratching and 
polishing process to the same cause — the great incumbent weight of a mass, which 
moving in a given and determinate direction, and passing over all minor obstacles, 
has produced that result by the moist sand and gravel at its base. Now, in our 
opinion, the great heaps of drift (whether derived from distant or adjacent hills) 
must at one period of their movement have produced similar impressions upon the 
subjacent rocks. For what was the condition of the drift at the particular periods 
of translation to which we refer, i. e. when rocks covered with gravel, sand and 
shingle, were raised up from beneath the sea? In its essential properties of weight, 
solidity, ductility, and materials for polishing and scoring at its base, a mass of 
moistened drift, one or two hundred feet in height, and a mile or two in length, 
must have embodied nearly all the properties of a glacier, the nature of the move- 
ment and the actual state of such mass of detritus being properly understood. 
Polished and scored surfaces of rock were, indeed, well known before the glacial 
theory came into fashion. They were long ago pointed out by Sir James Hall, 
Dr. Buckland and other observers, who then supposed that the striae were due to 
the rush of torrents in given directions, hurling with them stones and gravel. The 
objection to this explanation is, as before said, that the ordinary torrential action 
of water is too irregular to have produced a general parallelism of striae. But in 
bringing to the mind’s eye, as we here attempt to do, the manner in which masses 
of moist and pliant detritus were shouldered oft’ the sides of mountains and hills 
or forced through gorges, we must recollect that, in the cases to which we appeal, 
we have to treat of materials which, previously under the sea, were subsequently and 
often violently thrown off into depressions upon the elevation of the bottom of that 
sea or the lowering of an adjacent tract. The first effect of such a process would 
be to pour off large waves of translation with many loose materials, but the greater 
heaps of broken matter beneath such waves being comparatively drained by the 
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