Near Eternity.

A quarryman, dismissed because of intoxication, blames Billy, the mail clerk, and seeks revenge. He steals several sticks of dynamite, climbs to the top of the mail crane and ties to the explosives to the mail bag. Helen sees what is taking place, climbs to the arm and unties the dynamite. With the passenger train a short distance away, she hurls the explosive away just as the train approaches.