[1]1
DEPARTMENT OF GEOLOGY,
LELAND STANFORD JUNIOR UNIVERSITY,
PALO ALTO
Stanford University (p. o.), California,
Feb[ruary] 21 1894.
My dear Dr. Wallace:-
I thank you for the list of books relating to River pollution; it was just what I needed.
I have read your very interesting articles in the Fortnightly Review2,3 with great pleasure. You make the case a pretty plain one, and if I could give you the data you mention from direct observation on a stream flowing from an Alaskan glacier I think you might properly call the case closed. I believe I can get observations made in Alaska for a month, but it would cost more than I could raise to carry them over a year. But there are two difficulties in the way of such observations: 1st, it would be necessary to find a glacier that received had no debris upon its upper surface; 2nd, the stream flowing from it would have to be above the reach of tides. For if there were material brought down on the surface the sediments discharged would not fairly represent ice erosion, and if the tides reached the ice there would be almost insurmountable difficulties introduced into the discharge observations. Will you not make some suggestions in regard to the work? I shall undertake the work in Alaska if there is a reasonable chance of getting trustworthy results.
In 1833 we had a pretty warm discussion of on the subject of glacier erosion in this country. You will find a short account of it in Science Vol. II. Sept[ember]. 7 1883, p[age]. 320, and in [2] the Proc[eedings]. [of the] Am[erican]. Ass[ociation]. [for the] Adv[ancement]. [of] Sci[ence]. Vol XXXII, 1883 pp [pages] 200-201. Newberry4 in the latter place gives some interesting figures, and in the former paper Lesley5 gives it as his opinion that ice work is comparable to sand-papering a board. He gives this estimate of the comparative values of the agents mentioned
Cutting power of ice = 1.
" " " rainwater = 10.
" " " acidulated water = 100.
" " " ice set with stones = 1000.
" " " water set with stones = 10,000.
Newberry however, spoke of this table as the "figments of the imagination"[.]
In the Sixth Annual Rep[or]t. of the Director of the U[nited]. S[tates]. Geol[ogical]. Survey (1884-5) p[age]. 208, Chamberlin6, who is facile princeps7 on glacial geology in this country, shows the amount of drift in parts of the northern U[nited]. S[tates]. He and I have talked over this subject more or less, and as he confines himself usually to the facts that bear on it, what he says is always valuable.
G. F. Wright8 is a book-maker, and whatever field-work he does is of a very slip-shod kind, so that no importance can be attached to his opinions. Lelsley Lesley who has always opposed the idea of great erosion by ice, presents what he considers as evidence on his side on pp. [pages] 12 [sic] and XIII and XIV of Report Z (Terminal Moraine) of the Pennsylvania survey9. This consists of the two profiles of a mountain, one where it that has been glaciated and the other where it has not — necessarily very shaky evidence. Tarr10 has just called attention to the fact that Cayuga Lake in New York State is in a Ro rock basin. His paper hasn’t been published yet.
With best wishes, | very truly y[ou]rs | J. C. Branner11 [signature]
Status: Draft transcription [Letter (WCP2208.2098)]
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Please cite as “WCP2208,” in Beccaloni, G. W. (ed.), Ɛpsilon: The Alfred Russel Wallace Collection accessed on 28 April 2024, https://epsilon.ac.uk/view/wallace/letters/WCP2208