Letter icon
Letter 1120

Darwin, C. R. to Milne-Home, David

20 [Sept 1847]

    Summary Add

  • +

    Comments on paper by DM ["On the parallel roads of Lochaber", (1847) Trans. R. Soc. Edinburgh 16 (1849): 395–418]. "I am not in the least convinced about the Barriers … [but] I am very much staggered in favour of the ice-lake theory of Agassiz & [William] Buckland." Will "send a letter to the Scotsman, in which I give briefly my present impression".

  • +

    Cites facts mentioned in South America possibly of use to DM.


Down Farnborough Kent


Dear Sir

I am much obliged by your note. I returned from London on Saturday & I found there your Memoir, which I had not received, owing to the Porter having been out when I last sent to the Geolog. Soc.— I have read your Paper with the greatest interest & have been much struck with the novelty & importance of many of your facts. I beg to thank you for the courteous manner in which you combat me, & I plead quite guilty to your rebuke about demonstration. You have misunderstood my paper in a few points, but I do not doubt that is owing to its being badly & tediously written.

You will, I fear, think me very obstinate when I say that I am not in the least convinced about the Barriers: they remain to me as improbable as ever. But the oddest result of your paper on me (& I assure you, as far as I know myself, it is not perversity) is, that I am very much staggered in favour of the ice-lake theory of Agassiz & Buckland; until I read your important discovery of the outlet in Glen Glastig I never thought this theory at all tenable. Now it appears to me that a very good case can be made in its favour. I am not, however, as yet a believer in the ice-lake theory, but I tremble for the result.

I have had a good deal of talk with Mr Lyell on the subject, & from his advice I am going to send a letter to the Scotsman, in which I give briefly my present impression, (though there is not space to argue with you on such points, as I think I could argue) & indicate which points strike me as requiring further investigation with respect, chiefly, to the ice-lake theory, so that you will not care about it. If my letter be inserted I will send you a copy, & with my best thanks for your valuable & most interesting Memoir

I beg to remain | dear Sir | Yours sincerely | C. Darwin
D. Milne Esqe

P.S. | Some facts, mentioned in my Geology of S. America, p. 24, with regard to the shoaling of the deep fiords of T. del Fuego, near their Mouths, & which I have remarked would tend, with a little elevation to convert such fiords into lakes with a great mound-like barrier of detritus at their mouths, might, possibly, have been of use to you, with regard to the lakes of Glen Roy.

    Footnotes Add

  • +
    f1 1120.f1
    The date is based on CD's Account Book (Down House MS), in which he recorded the expenses of a trip to London on Saturday, 18 September 1847.
  • +
    f2 1120.f2
    Milne 1847b, the privately printed version of Milne 1849.
  • +
    f3 1120.f3
    See letter to Charles Lyell, 8 [September 1847], n. 5.
  • +
    f4 1120.f4
    In a modification of Thomas Dick Lauder's barrier theory (Dick 1823), Milne stated that there was a blockage ‘of some sort’, probably consisting of detritus which had disappeared through the process of erosion (Milne 1847b, p. 10; 1849, p. 404). CD rejected Milne's theory because there was no physical evidence that these barriers ever existed, particularly in an area whose features appeared to be entirely preserved. See ‘Observations on the parallel roads of Glen Roy’, Collected papers 1: 99.
  • +
    f5 1120.f5
    See letter to Charles Lyell, 8 [September 1847], n. 9.
  • +
    f6 1120.f6
    In September 1846, when examining the parallel roads, Milne discovered a col in Glen Glaster that corresponded in height with the middle shelf of Glen Roy. CD had stated that the middle shelf was ‘not on a level with any watershed’ (Collected papers 1: 92). See also letter to Charles Lyell, 8 [September 1847], n. 18.
  • +
    f7 1120.f7
    See letter to the Scotsman, [after 20 September 1847].
Maximized view Print letter