because, 1st, the receding water must have been that of a lake in Glen
Spean, and of the sea in the other valleys of Scotland, where I saw similar
buttresses at many levels; 2nd, because the outlets of the supposed lakes
as already stated seem, from Mr. Milne's statements, too much worn and too
large; 3rd, when the lake stood at the three-quarters of a mile shelf the
water from it must have flowed over ice itself for a very long time, and
kept at the same exact level: certainly this shelf required a long time
for its formation; 4th, I cannot believe a glacier would have blocked up
the short, very wide valley of Kilfinnin, the Great Glen of Scotland also
being very low there; 5th, the country at some places where Mr. Milne has
described terraces is not mountainous, and the number of ice-lakes appears
to me very improbable; 6th, I do not believe any lake could scoop the rocks
so much as they are at the entrance to Loch Treig or cut them off at the
head of Upper Glen Roy; 7th, the very gradual dying away of the terraces at
the mouth of Glen Roy does not look like a barrier of any kind; 8th, I
should have expected great terminal moraines across the mouth of Glen Roy,
Glen Collarig, and Glaster, at least at the bottom of the valleys. Such, I
feel pretty sure, do not exist.

I fear I must have wearied you with the length of this letter, which I have
not had time to arrange properly. I could argue at great length against
Mr. Milne's theory of barriers of detritus, though I could help him in one
way--viz., by the soundings which occur at the entrances of the deepest
fiords in T. del Fuego. I do not think he gives the smallest satisfaction
with respect to the successive and comparatively sudden breakage of his
many lakes.

Well, I enjoyed my trip to Glen Roy very much, but it was time thrown away.
I heartily wish you would go there; it should be some one who knows glacier
and iceberg action, and sea action well. I wish the Queen would command