7th Dec. 1859
My dear Clausius.
Will you have the kindness to assist me in the following matter.
I am anxious to put Agassiz’s labours on the glaciers1 in a fair light before the English public as I think he has been neither justly nor generously treated.
I am very anxious to learn when he first spoke to Mr Wild2 about engaging him to make a survey of the glacier of the Aar.3
I know that Herr Wild made measurements upon the glacier in 1842: but I want to know whether Agassiz did not bespeak his Services in 1841, or at all events early in 1842.
Would you ask Mr Escher von d. Linth4 whether he and Agassiz did not make an arrangement in 1840 to determine the velocity at various points across the Aletsch5 (and across the Aar glacier,) I believe they actually set up posts, which however on account of not being sunk sufficiently deep were of no use.
In 1841 Agassiz set up a series of posts on the Aar glacier and in 1842 their motion was determined by Mr Wild.6 About 3 weeks previously Forbes had determined the motion of the Mer de Glace: but I believe notwithstanding the speed with which he communicated his results to the Editor of the Edinburgh Philosophical Journal,7 that Agassiz was beforehand with him in publication.
I tell you frankly my impression that judged of by the laws tacitly adopted by scientific men, the proceeding of Forbes in this matter8 was not generous; and Agassiz has suffered from it in England up to the present time. I am anxious to do him justice in my little book & therefore ask you to be kind enough to obtain from M. Wild & M. Escher the above information for me.
Would you also kindly inform me where the papers of Mayer on the dynamical theory of heat are to be found.9
Finally would you ask M. Mousson whether any other writer besides Agassiz ever asserted that the sides of the glacier move more quickly than the centre. People say here that this was the general opinion, before the researches of Forbes.10
Ever yours most truly | John Tyndall
RI MS JT/1/T/179
Agassiz’s labours on the glaciers: Aggasiz undertook research on the movement and nature of glaciers from the 1830s onwards. His publications on glaciers include J. L. R. Agassiz Études sur les glaciers (1840); J. L. R. Agassiz, ‘Observations on the glacier of the Aar’, Edinburgh New Philos. J., 38 (1842), pp. 339–402; J. L. R. Agassiz, ‘Observations sur le glacier de l’Ааг’, C.R. Acad R. Sci. Paris. 15 (1842), pp. 284–8; J. L. R. Agassiz, ‘The glacial theory and its recent progress’, Edinburgh New Philos. J., 33 (1842), pp. 217–83.
Mr Wild: Johannes Wild (1814–94), a Swiss engineer, cartographer, and professor in Zurich.
glacier of the Aar: glacier system in the Bernese Oberland in Switzerland.
whether he and Agassiz did not make an arrangement in 1840 to determine the velocity at various points across the Aletsch (and across the Aar glacier): Arnold Escher von der Linth sent Tyndall a letter outlining his and Agassiz’ work, though requesting that he did not use the information in ‘war of priority’, see letter 1670.
Aletsch: the largest glacier in the Alps.
their motion was determined by Mr Wild: see for example Wild’s measurements in Louis Agassiz, Système glaciaire ou recherches sur les glaciers (Paris: Victor Masson/Leipzig: L. Voss, 1847).
Forbes had determined the motion of the Mer de Glace … communicated his results to the Editor of the Edinburgh Philosophical Journal: see ‘Professor Forbes’ Account of his recent Observations on Glaciers. Communicated in the following Letters to the Editor, Professor Jameson’, Edinburgh New Philos. J., 33 (1842), pp. 338–52.
the proceeding of Forbes in this matter: Tyndall was referring to the accusations levelled against Forbes that he had been dishonest in his academic dealings with Agassiz. See F. F. Cunningham, James David Forbes: Pioneer Scottish Glaciologist (Edinburgh: Scottish Academic Press, 1990).
Would you also kindly inform me where the papers of Mayer on the dynamical theory of heat are to be found: This is significant, as Tyndall would later champion Mayer’s priority in discovery of conservation of energy. See also letter 1674.
before the researches of Forbes: see for example, Forbes’s Travels through the Alps of Savoy (see letter 1594, n. 13).
Please cite as “Tyndall1664,” in Ɛpsilon: The John Tyndall Collection accessed on