Replica source: Yosemite National Park - Waterfalls - Hetch Hetchy Waterfalls. Joseph M. Riddle Correspondence (1841-1914), University of the Pacific, email permission from University of the Pacific Libraries, Stockton CA, https://scholarlycommons.pacific.edu/jmd/241/.

Yosemite National Park - Mountains - Half Dome - North Face of Half Dome with notes on glacial action. Joseph M. Riddle Correspondence (1841-1914), University of the Pacific, email permission from University of the Pacific Libraries, Stockton CA, , https://scholarlycommons.pacific.edu/jmd/208/.