Western writer Dane Coolidge (1873-1940) was also a photographer. Rummaging through old magazines online I came across an article by him about working cowboys in Arizona, fully illustrated with his photographs. The article appeared in a 1904 issue of Sunset Magazine. His book Cowboys of Arizona was published in 1938. His first novel Hidden Water (1910) was reviewed here at BITS a while ago. Find it here.
I like the hip-slung posture of the cowpuncher in the background. I believe it is supposed to be characteristic of the Texas cowboy. You see Paul Newman affecting it in the posters for the movie Hud.
Coming up: Charles Duff Stuart, Casa Grande (1906)