
I'm not entirely sure how I heard about John Muir or his writings, but after poking around GoodReads for a while, I settled on picking-up his journal, My First Summer in the Sierra (1911), as a starting point. Most of the reviews on the book that I read kept stressing "as a journal..." or "this is not a novel..." I didn't really get why people kept repeating this point until I read it myself. This is most definitely a cut and dry journal. It has not been heavily edited to follow any plot structure. It can be repetitive. With all this, it was still an enjoyable read.

"Horseshoe Bend, Merced River" and "One of the Tributary Fountains of the Tuolumne Cañon
Waters, on the North Side of the Hoffman Range," both by John Muir
That being said, I vacillated between being completely absorbed in the book to being bored out of my mind. I couldn't place my finger on it at first, but I quickly figured out what my issue was with the book. While I very much enjoyed Muir's description and narration of the animals he saw during his camping, I had zero interest in his descriptions of the trees and plants. The journal is split pretty much 50/50 between the two, so I flip flopped between being interested and disinterested as he switched focus. I continued reading despite this because his writing is beautiful. Every time I considered to just leave the book, he said something absolutely stunning.
"The broad-shouldered fronds held high on smooth stout stalks growing close together, overleaning and overlapping, make a complete ceiling, beneath which one may walk erect over several acres without being seen, as if beneath a roof. And how soft and lovely the light streaming through this living ceiling, revealing the arching branching ribs and veins of the fronds as the framework of countless panes of pale green and yellow plant-glass nicely fitted together—a fairyland created out of the commonest fern-stuff."
- June 13, In Camp on the North Fork of the Merced
I also really enjoyed his sense of humour, especially when it came to talking about the two-thousand sheep he was traveling with. He constantly talks about them as "the grand mass of mutton" or "the wool bundles." (Although my favorite was "the woolly locusts.") One example of his great sense of humour, yet admiration, when discussing animals is when he describes the woodchuck in Chapter 6:
The woodchuck (Arctomys monax) of the bleak mountain-tops is a very different sort of mountaineer—the most bovine of rodents, a heavy eater, fat, aldermanic in bulk and fairly bloated, in his high pastures, like a cow in a clover field. One woodchuck would outweigh a hundred chipmunks, and yet he is by no means a dull animal.
-July 31, Mount Hoffman and Lake Tenaya
The book is in the public domain, so you can read it online in many places, like The Sierra Club or get the ebook through an online bookshop. Though, I would recommend finding a print version, perhaps through your library, so you can see his drawings in full printed glory.

John Muir
PBS also has an article on John Muir and the role he had in creating our National Parks. In a similar vein, The Wilderness Warrior: Theodore Roosevelt and the Crusade for America is a book I started a long time ago and put down. I should pick it up again sometime soon. Has anyone read it?