Page:Popular Science Monthly Volume 5.djvu/467

Rh candidate for the Copley medal, which the Council of the Royal Society did not grant. He was angry at the time; but it pleases me to remember that subsequently in the Athenæum Club he renewed acquaintance with me, and gave me the benefit of his most agreeable and instructive conversation about glaciers.

The letter from Dr. Playfair can also be placed in a moment in its proper relation to other facts. A foot-note at page 195 of the first edition of "Heat as a Mode of Motion" runs thus: "Since the above was written, the 'Glaciers of the Alps' has been published, and soon after its appearance a 'Reply' to those portions of the work which referred to Rendu was extensively circulated by Principal Forbes. For more than two years I have abstained from answering my distinguished censor, not from inability to do so, but because I thought, and think, that within the limits of the case it is better to submit to misconception than to make science the arena of a purely personal controversy." Not for two years, but for ten years did I permit, for peace' sake, this misconception to continue; it refers to allegations as to omissions made against me by Principal Forbes, and disposed of at p. 498 et seq., vol. xxii. of the Contemporary Review.

It will be seen at the place here referred to, that the strongest argument of Principal Forbes relates to a statement regarding crevasses made by Rendu; and Mr. George Forbes now contends for the correctness of his father's views. I can assure him, in all good temper and good faith, that he is hopelessly wrong; that his father entirely misapprehended Rendu; and that the argument founded on this misapprehension, though apparently so incontrovertible, and so damaging to me, is in reality not worth the paper on which it stands. During the lifetime of Principal Forbes I never once disturbed him in the enjoyment of his delusive triumph, and my life also would have passed without any attempt at refutation had not his biographers flaunted the argument again in my face, and compelled me to reduce it to the condition in which it appears in my last article. Had I, as alleged, been disposed to wound Principal Forbes, I should not have acted thus.

I had stated in the "Glaciers of the Alps," and in this Review, that some very important measurements made by Agassiz in 1841 and 1842, by which the differential motion of a glacier was demonstrated, had been ignored in all the writings of Principal Forbes. Though so much occupied with the subject, I was in absolute ignorance of the existence of these measures myself until my attention was drawn to them by Sir Charles Wheatstone, immediately before the publication of the "Glaciers of the Alps." Prof. George Forbes now charges me with forgetfulness of the fact that it was his father who suggested to M. Agassiz the measurements he made; meaning thereby, I suppose, to intimate that his father was not called upon to recognize measurements which were the result of his own instruction.