Ɛpsilon

From J. W. Judd   8 January 1882

Hurstleigh, | Kew—

8th. Jany. 1882.

Dear Mr. Darwin,

I am very glad to find that in the current number of ‘Nature’ your son has given us his views on the points of geological theory touched upon by Mr. Ball in his lecture. Without such an explanation as your son has given, I cannot but think that the speculations were calculated to do—mischief.1 When Mr. Ball says the phenomena he so graphically described took place not less than 50 millions of years ago many would infer that it might not be much more than that time ago.2

Now, however willing one may be to concede an increase of intensity in the existing forces during past time—yet when we see the Cambrian strata with thousands of feet of excessively fine sediments, everywhere abounding with the tracks & borings of soft bodied creatures, it is hard to believe that they are the result of the action of such terrific grinding mills as are described to us.

Unless the average height of the land were much greater than at present, terrestrial life would have been almost impossible with tides of 600 feet. What, however, seems to me to be the strongest argument against excessive tides at these early periods is the existence of such grand estuarine deposits as those of the Carboniferous period. Now the action of tides, as De la Beche so well pointed out, is quite antagonistic to the formation of deltas.3 I find it very hard to believe that such grand delta-deposits as those of the Coal-measures could possibly have been formed with tides of even double the height of those of the present day—as your son more modestly suggests.

I am very glad to see that your son dwells on the importance of the subaerial forces in producing denudation in contradistinction to that of the sea—4 I very much doubt whether Ramsay would approve of Hull’s application of his ideas about ‘plains of Marine denudation’—5 It has always seemed to me that the supposed proofs of such plains of Marine denudation are not very strong, for the generally uniform height of mountains in a district like the Highlands may very well be accounted for if we remember that the higher we go the more powerful become the forces of atmospheric erosion.

I was so interested by my recent conversation with you upon this subject, that I hope you will forgive my troubling you with this letter.

Hoping you are better than when I saw you in town6 I remain, | Yours very faithfully | John W. Judd

P.S. I am sure that all geologists will unite with me in thanking your son for the very fair and clear manner in which he has put the matter before the public.

1
In a lecture published in Nature, Robert Stawell Ball argued that tidal forces played a much larger role in shaping geological formations in the past, owing to the closer proximity of the moon to the earth (see Ball 1881, pp. 81, 102–4); he drew partly on George Howard Darwin’s recent work on tidal theory (G. H. Darwin 1878c). George responded with a short article in Nature, 5 January 1882 (G. H. Darwin 1882); he criticised some of Ball’s speculations, especially on tidal waves of over 600 feet, and added that his own estimates of tides two or three times those of the present were probably excessive.
2
See Ball 1881, p. 82.
3
Henry Thomas De la Beche; on the formation of deposits in estuaries and the adverse action of tides, see De la Beche 1846, pp. 15–17.
4
George noted that most geologists at that time attributed denudation to a variety of factors, including air, rain, rivers, and oceanic waves. In earlier geological times, he remarked, the more rapid alternation of day and night would probably lead to stronger storms and greater rainfall, and the increased rotation of the earth would produce more violent trade winds. He concluded that there was no geological evidence for the extreme tidal forces described by Ball, and suggested that such forces might have occurred in ‘pregeological periods’ (G. H. Darwin 1878c, p. 213).
5
Edward Hull’s response to Ball was published in Nature, 22 December 1881, pp. 177–8; he used Andrew Crombie Ramsay’s study of denuded planes, formed from uneven and ‘most obdurate rocks over hundreds or thousands of square miles’ to support Ball’s theory of a ‘stupendous tidal grinding-engine’ in early geological times. Ramsay had emphasised subaerial rather than marine forces in his work on denudation (see Ramsay 1878, pp. 31–6, 341–3, 496–9, Correspondence vol. 12, letter from A. C. Ramsay, 10 July 1864 and n. 3, and Correspondence vol. 17, letter to A. C. Ramsay, 3 February [1869]).
6
CD was in London from 13 to 20 December 1881 (Emma Darwin’s diary (DAR 242)).

Please cite as “DCP-LETT-13604,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-13604