Agassiz does not pretend that direction
of scratches is hostile to floating ice. By the way, how do you and
Buckland account for the "tails" of diluvium in Scotland? (499/3. Mr.
Darwin speaks of the tails of diluvium in Scotland extending from
the protected side of a hill, of which the opposite side, facing the
direction from which the ice came, is marked by grooves and striae
(loc. cit., pages 622, 623).) I thought in my appendix this made out the
strongest argument for rocks having been scratched by floating ice.

Some facts about boulders in Chiloe will, I think, in a very small
degree elucidate some parts of Jura case. What a grand new feature all
this ice work is in Geology! How old Hutton would have stared! (499/4.
Sir Charles Lyell speaks of the Huttonian theory as being characterised
by "the exclusion of all causes not supposed to belong to the present
order of Nature" (Lyell's "Principles," Edition XII., volume I., page
76, 1875). Sir Archibald Geikie has recently edited the third volume of
Hutton's "Theory of the Earth," printed by the Geological Society, 1899.
See also "The Founders of Geology," by Sir Archibald Geikie; London,
1897.)

I ought to be ashamed of myself for scribbling on so. Talking of shame,
I have sent a copy of my "Journal" (499/5. "Journal and Remarks,"
1832-36. See note 2, page 148.) with very humble note to Agassiz, as an
apology for the tone I used, though I say, I daresay he has never seen
my appendix, or would care at all about it.

I did not suppose my note about Glen Roy could have been of any use to
you--I merely scribbled what came uppermost. I made one great oversight,
as you would perceive. I forgot the Glacier theory: if a glacier most
gradually disappeared from mouth of Spean Valley [this] would account
for buttresses of shingle below lowest shelf. The difficulty I put about
the ice-barrier of the middle Glen Roy shelf keeping so long at exactly
same level does certainly appear to me insuperable. (499/5. For a
description of the shelves or parallel roads in Glen Roy see Darwin's
"Observations on the Parallel Roads of Glen Roy, etc." "Phil. Trans. R.
Soc." 1839, page 39; also Letter 517 et seq.)

What a wonderful fact this breakdown of old Niagara is. How it disturbs
the calculations about lengths of time before the river would have
reached the lakes.

I hope Mrs. Lyell will read this to you, then I shall trust for
forgiveness for having scribbled so much. I should have sent