Asks for copy of CD's paper ["Ancient glaciers of Caernarvonshire", Collected papers 1: 163–71]. Gathers that drift of Moel Tryfan is glacial.
Believes Glen Roy roads formed later than submergence of Scotland.
Asks CD's opinion concerning relative chronology of various glacial deposits, particularly a flint tool find in the Ouse River near Bedford.
30 Sept. | 1861
My dear Darwin
I am afraid you will not have by you a spare copy of your welsh glacier paper alluded to in Jamieson's last—vol. 33 Edinb. Phil. Journ. 1842 if you have I shall be very glad of it— if not I will try & buy but can at any rate borrow it.
I gather from Trimmer & E: Forbes 1
Now I begin to have little doubt that the Glen Roy roads are later than the great submergence, if Scotland was ever submerged like Wales as very likely it was.
But how to make these three periods, 1
I now believe that at Bedford both these groups of mammalia were after the marine boulder-clay of that middle-county district.
[DIAG HERE] B oolite glaciated erratic R. Ossa above Bedford A oolite boulder drift B oolite
A is gravel containing freshw
At the bottom of A are human flint implements of the Amiens type used by men who lived when the valley was not so deep by 30 feet as now where the Oose flows.
These men lived, perhaps with Hippopot. major—after the elevation
of the sea-bottom of the boulder clay of Bedford.— Was this last coeval with
the marine drift of Wales? If so what were the relations in time between your last
Lanberris glaciers & the excavat
Falconer & Prestwich place El. antiquus as well as mammoth of the caves of S. Wales as post glacial.
I hope you will not merely wish Jamieson & me joy of having to solve these problems but give us an hypothesis at least about some of them.
You may use the sea for your fringes above the pass of Mackul now that we give you a marine submergence before the shelves.
To save my copying these queries for M
In the Norfolk cliffs Elephas antiquus was anterior to the erratics & glacial till—so it was near Zurich in Switzerland anterior to the largest Alpine erratics. But it seems to me to have been at Bedford a post-glacial beast.
Some of our Scotch peat bogs are surrounded by till & yet they & subjacent marl contain like the Danish peat bogs no extinct mammalia— Why is this.— The Danish peat lies also in depressions in drift & unstratified moraine-like boulder clay—
Were these glacial formations so modern that the fauna which immediately succeeded, a rich one, contained no extinct mammalia?
believe me | my dear Darwin | ever sincerely yours | Cha Lyell
- f1 3270.f1`Notes on the effects produced by the ancient glaciers of Caernarvonshire, and on the boulders transported by floating ice', Edinburgh New Philosophical Journal 33 (1842): 352--63. The paper originally appeared in the London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science 21 (1842): 180--8 (Collected papers 1: 163--71). Thomas Francis Jamieson referred to the paper in his letter to Lyell, 27 September 1861 (see Correspondence vol. 9, Appendix IX).
- f2 3270.f2Trimmer 1831. In his paper on glaciation in North Wales, CD stated that Joshua Trimmer `was one of the earliest observers of the scores and other marks on the rocks of North Wales.' (see Collected papers 1: 170 n. 5). Moel Tryfan is a hill in North Wales that is 1192 feet above sea level.
- f3 3270.f3In Forbes 1846, Edward Forbes discussed the distribution of fossil marine shells and some extant British forms collected by Trimmer on Moel Tryfan. The confused mixture of species from different sea-depths suggested to him that some disturbing force had been in operation (Forbes 1846, p. 384). Lyell cited Trimmer and Forbes on this point in C. Lyell 1863, p. 267.
- f4 3270.f4Ramsay 1852, p. 372.
- f5 3270.f5Lyell discussed these points in chapters 13 and 14 of C. Lyell 1863, both of which discussed the `Chronological relations of the glacial period and the earliest signs of man's appearance in Europe'. All of the species mentioned are post-Pliocene forms whose bones had been discovered in association with human artefacts (see ibid., pp. 156--9, 283). The topics Lyell mentions relate to his attempt, in writing up the results of his study of the antiquity of man, to synthesise the current knowledge of geological phenomena in the periods immediately antecedent and posterior to the first appearance of human remains.
- f6 3270.f6Lyell had visited the Biddenham gravel-pit near Bedford in April 1861, where remains of Elephas antiquus, E. primigenius, Rhinoceros tichorhinus, and Hippopotamus major were found in deposits that also contained rough flint implements used by ancient peoples (see K. M. Lyell ed. 1881, 2: 344 and C. Lyell 1863, pp. 163--6); these deposits extended back into the post-Pliocene period (see C. Lyell 1863, p. 207).
- f7 3270.f7Large numbers of ancient flint implements had been discovered in the gravel-pits near Amiens in France in the early 1850s. These, taken in conjunction with those previously uncovered near Abbeville in France and the findings of similar flint implements in association with the bones of extinct mammals in caves near Torquay, Devonshire, had convinced many naturalists that the antiquity of humankind was greater than had previously been thought (see C. Lyell 1863, pp. 94--105).
- f8 3270.f8CD described the clear signs of glaciation in the vale of Llanberis, North Wales, in his paper on the ancient glaciers of Caernarvonshire (see n. 1, above; see also Collected papers 1: 169--70).
- f9 3270.f9Falconer 1860. Both Hugh Falconer and Joseph Prestwich were experts in identifying the remains of extinct mammals in ossiferous caves.
- f10 3270.f10See letter to Charles Lyell, 22 September .