Page:Mannering - With axe and rope in the New Zealand Alps.djvu/161

Rh that they do not carry such a large quantity of detritus as those of the eastern slopes.

This disparity remains to be accounted for and awaits an explanation. I have a theory of my own upon the subject, which, however, as yet I would not like to put too strongly forward.

On both sides of Mount Cook, on Mount De la Bêche (ten miles further along the chain), and on a peak just north of the Hochstetter Dome (ten miles still further north) I have observed enormous exposed sections of the rock strata, which in each case dip at a steep angle from east to west, presenting slab faces, not easily disturbed by the action of the frost, to the westward, but broken and fast denuding faces ('basset' faces, as they are geologically termed) to the eastward. I am hoping at some future time to further investigate this interesting subject.

As the western glaciers, however, must descend steeper valleys than the eastern, I make no doubt that their rate of progress will be eventually ascertained to be greater than that of the latter, and this would militate largely against an accumulation of moraine upon the ice.

All sorts of queer notions as to what the surface of a glacier is like exist. Indeed I have often heard people inquire if it would be possible to skate upon it!

Let us for a moment imagine ourselves at the head of the great Tasman Glacier, 8,600 feet above sea-level. All around us is snow, either freshly fallen or merging into névé. We begin to walk down, and at first, upon