George Bird Grinnell,
Jack, the Young Ranchman: A Boy's Adventures in the Rockies
“ The horse, after some ineffectual struggles, lay still, breathing heavily, and with the sweat starting from his skin.Jack had by this time jumped down from the fence and approached the group of men."Keep behind him, son, and near his head; then he can't kick you, even if he does get his feet free," said Hugh."Why does Rube sit on his head, Hugh?" asked Jack."So's to keep him from getting up," was the reply. "Don't you know that if a horse is lying on his side, he can't get up unless he raises his head first. So when you throw a horse, if you don't want him to get up, just sit on his head." ”
