The information comes from a book titled Cow Country Cavalcade, which tells about cowboying in Wyoming in the 1880’s. The author tells a story about a cowboy who made a trip back East. For some reason he didn’t want people to know he was a cowboy, so he bought another type of hat to wear.
The first morning on the train, somebody asked him, “Where do you punch cattle?” The cowboy, somewhat astonished, asked, “How did you know I’m a cattlepuncher?”
The reply – “Because when you got up this morning, the first thing you did was put on your hat.”