Dear Sir

I am much obliged by your note. I returned from London on Saturday & I found there your Memoir,² 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.³ 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:⁴ 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;⁵ until I read your important discovery of the outlet in Glen Glastig⁶ 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 M^r 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,⁷ (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 Esq^e

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.