Page:Popular Science Monthly Volume 44.djvu/659

Rh bride"—which was rather hard upon plain folk, married twenty-one years, and blessed with, seven children to boot.

My friend's exploits as a mountaineer are sufficient evidence of his extraordinary physical vigor. I could manage a fair day's work in reasonable up-and-down walking myself, but I lacked his caprine sureness of head and foot; and, when it came to climbing, I was nowhere beside him. By way of compensation, I stood the wear and tear of London life better, though I had not much to boast of, even in that respect. From the first, Tyndall suffered from sleeplessness, with the nervous irritability which is frequently cause and consequence of that distressing malady. It is not uncommon for this state of the nervous system to find a vent in fits of ill temper; but, looking back over all the long years of our close intercourse, I can not call to mind any serious manifestations of that sort in my friend. Tyndall "consumed his own smoke" better than most people, and though that faculty is worthy of the highest admiration, I suspect that the exercise of it tells a good deal upon the furnace. When things got bad with him, his one remedy was to rush off to the nearest hills and walk himself into quietude. Pleasant are the recollections, for me and others, of such hard tramps, it might be in the Lake country, or in the Isle of Wight; in the Peak of Derbyshire, or in Snowdonia. On such excursions Tyndall was the life of the party, content with everything and ready for anything, from philosophical discussion and high-flying poetics, to boyish pranks and gymnastic comicalities.

Sometimes we traveled further afield. Thus, in 1856, we made an expedition to Switzerland which had a large influence on Tyndall's future. In 1845 I had my first view of a glacier, at the head of the Lac de Gaube in the Pyrenees; and when, ten years later, I was led to interest myself seriously in geology, in connection with the study of fossils, I read all I could lay hands on about these curious rivers of ice. At the same time Tyndall was occupied with his important investigations into the effects of pressure in giving rise to lamination, and I naturally heard a good deal about what he was doing. It struck me that his work might throw some light upon the production of the veined structure of glacier ice; and one day, when he was dining with us, I mentioned the notion that had come into my head. The upshot was that we, then and there, agreed to go and look into the facts of the case for ourselves. More suo, he would have nothing to do with speculation till that essential preliminary operation had been effected.