These letters were found by Graham White in the archives of the Kew Gardens, in England. John Muir had traveled with Sir Joseph Hooker and Professor Asa Gray on a botanical expedition in 1877 through the Mount Shasta region, and thereafter remained life-long friends.
- To Asa Gray, January 13, 1878: Description of the Yellow and Jeffrey Pines
- To Joseph Hooker, February 1, 1879: Description of Muir's geological and botanical studies of the Great Basin
- To Joseph Hooker, February 20, 1882: Muir's request for Hooker to support a bill to protect the Sequoias of the Kaweah and Tule Rivers The Tule River Sequoias are still unprotected despite designation as a National Monument in 2000.
- To Joseph Hooker, April 20, 1902: Personal recollections, travel plans, botanical musings
- To Joseph Hooker, October 20, 1904: Describing Muir's trip around the world
New Cache Of Muir Letters Discovered In England by Ron Limbaugh (explains source and origins of these letters)
Source: Kew Gardens archives, London, England; transcribed by Graham White