I always imagine, when the camera is pointed towards laborers, usually something along the lines of "when will this dumba.. get finished so we can get back to work", except in this case, the guy in the nice clothes at the far right looks like "whew its hot, man the gnats are bad, when do we eat". Just my interpritation.
Wish the camera man would have swung around and got a shot from the opposite direction, showing the Uintah's loading tracks and the minning camp in 1919 - a rarely photographed time period at that location.
Rodger