New York, 1896, later edition. 444 pp, ills. Tyndall was a well regarded scientist and climber whose best 1st ascent was the Weisshorn, and who competed with Whymper for the Matterhorn. This is a classic scientific treatise continuing the work of Agassiz and Forbes and dedicated to Faraday, a close friend and collegue at the Royal Institution. In 1860 Tyndall made an early assault on the Matterhorn which, together with two subsequent expeditions to Switzerland, formed the basis for this book and for the author's enthusiasm for mountaineering. Spine faded, internally clean with no foxing, spine has been repaired, Very Good.