eme of the scale of wonder
[to] the valleys of New South Wales) were formed exclusively by fresh
water. He underrates the power of sea, no doubt, but read his remarks
on valleys in the Sandwich group. I came to the conclusion in S. America
(page 67) that the main effect of fresh water is to deepen valleys, and
sea to widen them; I now rather doubt whether in a valley or fiord...the
sea would deepen the rock at its head during the elevation of the land.
I should like to tour on the W. coast of Scotland, and attend to this.
I forget how far generally the shores of fiords (not straits) are
cliff-formed. It is a most interesting subject.

I return once again to Coral. I find he does not differ so much in
detail with me regarding areas of subsidence; his map is coloured on
some quite unintelligible principle, and he deduces subsidence from the
vaguest grounds, such as that the N. Marianne Islands must have subsided
because they are small, though long in volcanic action: and that the
Marquesas subsided because they are penetrated by deep bays, etc., etc.
I utterly disbelieve his statements that most of the atolls have
been lately raised a foot or two. He does not condescend to notice
my explanation for such appearances. He misrepresents me also when he
states that I deduce, without restriction, elevation from all fringing
reefs, and even from islands without any reefs! If his facts are true,
it is very curious that the atolls decrease in size in approaching the
vast open ocean S. of the Sandwich Islands. Dana puts me in a passion
several times by disputing my conclusions without condescending to
allude to my reasons; thus, regarding S. Lorenzo elevation, he is
pleased to speak of my "characteristic accuracy" (560/2. Dana's
"Geology" (Wilkes expedition), page 590.), and then gives difficulties
(as if his own) when they are stated by me, and I believe explained
by me--whereas he only alludes to a few of the facts. So in Australian
valleys, he does not allude to my several reasons. But I am forgetting
myself and running on about what can only interest myself. He strikes me
as a very clever fellow; I wish he was not quite so grand a generaliser.
I see little of interest except on volcanic action and denudation, and
here and there scattered remarks; some of the later chapters are very
bald.

LETTER 561. TO J.D. DANA. Down, December 5th, 1849.

I have not for some years been so much pleased as I have just been
by reading your