Treat 'Em Rough(1919)

Daredevil cowboy Ned Ferguson is hired by John Stafford to stop the cattle rustling plaguing his ranch. On the way to the ranch Ned is bitten by a rattlesnake and is nursed by Mary Radford, who is writing a western novel. Ranch foreman Dave Leviatt tells Ned that Mary's brother Ben is behind the rustling. After Ben and Ned come to an understanding, Dave shoots Ben from under cover but Ben is sure that Ned double-crossed him. Mary will have nothing to do with Ned, even after Ned saves her life during a cattle stampede. Ned finally runs down the rustlers, and Mary sees him as a hero instead of merely putting him in her novel.