I found this bookplate--"Ex-libris Geoffrey Winthrop Young"--in a copy of Tudor Tracts 1532-1588, Archibald Constable and Co, 1903. I was tempted to remove it for my collection but I did a little googling first and it turns out Young was a famous mountaineer, author and poet.
Excerpted from wikipedia:
"Young made many new and difficult ascents in the Alps, including noted routes on the Zermatt Breithorn (the "Younggrat"), the west ridge of the Gspaltenhorn, on the west face of the Weisshorn, and a dangerous and rarely repeated route on the south face of the Täschhorn. His finest rock climb was the Mer de Glace face of the Grépon. In 1911, with H O Jones, he ascended the Brouillard ridge of Mont Blanc and made the first complete traverse of the west ridge of the Grandes Jorasses, and the first decent of the ridge to the Col des Hirondelles....He was elected president of the Climbers' Club in 1913...and later president of the Alpine Club."He published numerous collections of verse, books on mountaineering and the very entertaining sounding The Roof Climbers Guide to Trinity, "a satirical parody of pompous early alpine guides".
The book also contains a bookseller ticket from "Spottiswoode & Co., Ltd., 17 High Street Elton" and vocabulary notes on the rear endpaper (possibly in Young's hand).
Quite a cool find.