devices with which I proposed to overcome them. That Prof. Forbes reached the Mer de Glace in 1842, a few weeks before I went up the Glacier of the Aar, only gave him the opportunity of making a few days' observations at a time when I had already gained an annual average. That Prof. Forbes knew in 1841 of my intention to make this experiment I can affirm the more positively as he saw the iron bars with which I intended to bore the holes, and which had been carried up the glacier before he reached the Grimsel. That I was going to use instruments of precision in these measurements he must have understood, since I repeatedly mentioned my purpose of making a trigonometrical survey of the glacier the following year. Whether I at any time mentioned the theodolite I cannot remember now. But I am sure that he never suggested any thing to me.
"Allow me one more remark. Everybody knows that I am a naturalist, and not a physicist. My interest in the glaciers arose from a desire to learn something of the mammoth of Siberia, after I had become convinced by Charpentier that the glaciers of Switzerland were much more extensive in earlier times than now. It struck me that there might be some connection between the burial of these gigantic mammalia in the arctic regions and the wider range of glaciers in Switzerland; I am one of those who believe, as you expressed it in your short and characteristic speech at Geneva, that 'Nature is One,' and so I was led to study the accumulations of ice without the necessary preparation. This you cannot fail to perceive in reading the accounts of my successive attempts, and for this, I hope, some allowance will hereafter be made."
This account fairly tallies with the statement of Prof. Forbes in his "Travels," quoted in his "Life" (p. 503):
"Far from being ready to admit, as my sanguine companions wished me to do in 1841, that the theory of glaciers was complete, and the cause of their motion certain, after patiently hearing all that they had to say, and reserving my opinion, I drew the conclusion that no theory which I had then heard of could account for the few facts admitted on all hands, and that the very structure and motions of glaciers remained still to be deduced from observation."
Incomparably greater than Forbes in his own field, the want of physical knowledge, to which Agassiz refers at the conclusion of the foregoing letter, rendered him, on this particular ground, a mere child in comparison with his guest. Still, if the statement which I have italicised in Agassiz's letter express a fact, then, while entertaining no doubt that Prof. Forbes justified his conduct to his own mind, I leave it to others to judge whether it would not be an evil day for the frankness of scientific intercourse if such conduct should become general.
It is difficult at the present day and hour to convey an idea of the stir caused by the communication of our joint paper to the Royal Society by Mr. Huxley and myself; but many of us remember the violent discharge of letters which followed that event. Had I in those days a tendency to be puffed up, the circumstances were certainly such as might exalt my self-importance. But, as a matter of fact, the whole business was exceedingly saddening to me. For two years I endeavored, while not flinching from what I held to be the duty of a
