 In the "Exploration of the Sierra Nevada", Francis P. Farquhar describes Cotter as, "an indomitable mountain-climber whose Services were of great value in more than one branch of the work".Mount Whitney, the highest mountain in the contiguous states was first discovered in July 1864 by Clarence King and Richard Cotter.After Cotter completed the mapping in Yosemite late 1864, he signed up to work on the Western Union Telegraph Expedition to British Columbia and Alaska, with the goal of providing a telegraph link from Asia through Alaska by way of Bering Strait.