Partial autograph manuscript, one page, 8.25 x 11.75, part of a page from Muir’s working draft of The Mountains of California. Headed at the top, “III. The Passes,” Muir writes, in full: “The sustained grandeur of the Alps is forcibly illustrated by the fact that throughout their whole extent there is not a single pass lower than 8,000 feet above the level of the sea. In a distance of a hundred & forty miles, between Lat 36° 20′ & 38°, the lowest I have yet found exceeds 9,000 feet, while the average height upwards of 11,000. A carriage road has been constructed through what is known as the Sonora Pass, on the head of the Stanislaus and Walker’s rivers, the summit of which is 9,607 feet above the sea. Substantial wagon-roads have also been built through the Carson & Johnson passes.” On the reverse, Muir has penned “Passes of Alps Full Copy (nearly).” In very good condition, with tape reinforcement to reverse of horizontal folds and some light edge toning. Pre-certified PSA/DNA and RR Auction COA.