[John Muir]


[Jeanne C.] Carr


image preview


[15]means I was enabled to measure the flow of the glacier with great exactness. Examining this stake in 24 hours after setting it, I found that it had been carried down about 3/16 of an inch At the end of four days I again examined it & found that the whole downward motion was 13/16 of an inch showing that the flow of this glacieret was perfectly regular. In accounting for these narrow lane canons so common here I had always re[illegible]ed] them to ice action in connection with special conditions of cleavage, & I was gratified to find that their formation was still going on. This Hoffman glacieret is about 1000 feet long by 15 to 30 feet wide. & perhaps about 100 feet deep in deepest paces. Now there Mrs Carr I must[in margin: hasten back to the Mtns, I'll go tomorrow] 00625[There is a line through whole page] 4 [12] The Sierras adjacent to the Yosemite Valley are composed of Slabs of granite set on edge at right angle, to the direction of the range or about N 30° E, S 30 W Also lines of cleavage cross these running nearly parallel with the main range. Also the granite of this region has a horizontal cleavage or strabfication. The first men- tioned of these lines have the fullest development & give direction & character to many valleys & canyons & determine the principal features of many rock forms No matter how hard & domed & homog[illegible]eous the granite may be it still possesses these lines of cleavage wh require only simple conditions of moisture, time etc for their development. But I am not


Yosemite Valley

Date Original

1872 Oct 8


Original letter dimensions: 20.5 x 25.5 cm.

Resource Identifier


File Identifier

Reel 02, Image 0953

Copyright Statement

The unpublished works of John Muir are copyrighted by the Muir-Hanna Trust. To purchase copies of images and/or obtain permission to publish or exhibit them, see

Owning Institution

University of the Pacific Library Holt-Atherton Special Collections. Please contact this institution directly to obtain copies of the images or permission to publish or use them beyond educational purposes.

Copyright Holder

Muir-Hanna Trust

Copyright Date


Page Number

Page 7


John Muir, correspondence, letters, author, writing, naturalist, California, correspondent, mail, message, post, exchange of letters, missive, notes, epistle