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Darwin Correspondence Project

To Charles Lyell   8 May [1855]

Down.

May 8th

My dear Lyell

The notion you refer to was published in Geological Journal Vol IV (1848) p 315,1 with references to all the cases, which I cd. collect of Boulders apparently higher than parent-rock.—

The argument of probable proportion of rock dressed by sea-ice, compared to land glaciers, is new to me.—2 I have often thought of the idea of viscosity & enormous momentum of great icebergs & still think that the notion, I pointed out in appendix to Ramsay’s Paper3 is probable & can hardly help being applicable in some cases. I wonder whether the Phil. Journal wd. publish it, if I could get it from Ramsay or Geolog. Socy. 4 If you chance to meet Ramsay will you ask him whether he has it.— I think it wd. be perhaps worth while just to call the N. American geologists’5 attention to the idea; but it is not worth any trouble, & I am tremendously busy with all sorts of experiments.— By the way, Hopkins at the Geolog. Soc. seemed to admit some truth in idea of scoring by (viscid) icebergs.—6

If the Geolog. Socy. takes so much to judge of truth of notions, as you were telling me in regard to Ramsay’s Permian glaciers,7 it will be as injurious to progress, as French Institute8

Ever your’s | C. Darwin

Footnotes

A reference to CD’s paper, ‘Transportal of erratic boulders from a lower to a higher level’ (Collected papers 1: 218–19). Lyell was at this time investigating the possibility of a glacial period having occurred before the Pleistocene, as suggested by Andrew Crombie Ramsay on the basis of fieldwork in Wales (Ramsay 1852 and 1855). Ramsay had described erratic boulders high up in the Welsh mountains as evidence for some glacial activity prior to the geological actions that left deposits of ‘drift’. CD, on the other hand, believed such boulders were contemporaneous with the drift and had indeed been transported to great heights by the agency of floating ice.
CD refers to Ramsay’s statement that ‘the peculiar forms, polish, and markings of many of the stones indicate that these characteristics have been produced by the agency of ice of the nature of glaciers, for mere coast-ice would have picked up and drifted away numerous rounded pebbles from the beach, and not a great majority of angular flattened stones, such as form the breccias wherever they occur.’ (Ramsay 1854, p. 200).
Probably a reference to Ramsay 1852, which was originally read at the Geological Society on 26 March 1851 and then withheld by Ramsay in order to revise his argument after a critical response (Geikie 1895, pp. 177–8). As published, the paper had no reference to any appendix by CD but contained matter which may well have once been supplemented by CD’s work on viscous icebergs (eventually published as a separate paper, see n. 5, below). Ramsay had argued that scratch marks on the rocks of Anglesea were due to floating ice, indicating that the land was then partially submerged. The scratches, however, ran counter to the line of the valleys, i.e., they indicated that the icebergs must have travelled transversely across the valleys rather than along them (Ramsay 1852, p. 374). CD’s work on icebergs treated precisely this question and suggested that icebergs possessed a certain viscosity which made the bottom run closely over the sea bed and enabled currents to push them over irregularities of topography (Collected papers 1: 252–3).
The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science, in which CD’s paper ‘On the power of icebergs to make rectilinear, uniformly-directed grooves across a submarine undulatory surface’ appeared in August 1855 (Collected papers 1: 252–5).
Probably William Barton Rogers and Henry Darwin Rogers. Lyell had also geologised with the Canadian John William Dawson on his second visit to America in 1852 (see K. M. Lyell ed. 1881, 2: 178–84).
In an earlier letter to Lyell, 7 June [1853], CD reported that William Hopkins had supported the idea of plastic icebergs being driven in straight courses by their momentum.
Ramsay had presented his evidence for the existence of glaciers during the Permian period in a paper read to the Geological Society on 21 February 1855 (Ramsay 1855). Many geologists doubted the possibility of a cool period long before the Pleistocene because it contradicted widespread assumptions about the gradual cooling of the earth. The reception of Ramsay’s paper is described in Geikie 1895, pp. 228–9: The subject had been rather laughed at by [Henry] De la Beche, who said, ‘As to the scratching of breccia fragments— “’tis their nature to”—a tumble-down house will give plenty of them; and then as to old localities for the fragments, independently of not having cakes which have been eaten, who the dickens, in such places, can say what rocks are beneath the sprawl of New Reds?’ Lyell, however, took a much more serious view of the matter, and with that eager enthusiasm so characteristic of him, threw himself into it, and endeavoured to master all the evidence.
L’Institut de France, composed of five academies, one of which was the Académie des Sciences.

Summary

Mentions his paper ["Transportal of erratic boulders", Collected papers 1: 218–27]. Discusses ice-borne rock. Reference to unpublished paper on icebergs [?"Power of icebergs to make grooves", Collected papers 1: 252–5]. Remarks on scoring by icebergs. Comments on judgment of theories by Geological Society.

Letter details

Letter no.
DCP-LETT-1679
From
Charles Robert Darwin
To
Charles Lyell, 1st baronet
Sent from
Down
Source of text
American Philosophical Society (113)
Physical description
4pp

Please cite as

Darwin Correspondence Project, “Letter no. 1679,” accessed on 17 June 2019, http://www.darwinproject.ac.uk/DCP-LETT-1679

Also published in The Correspondence of Charles Darwin, vol. 5

letter