mail car n. A railway car of special design used for the transportation and sorting of mail en route to its destination, and having employees of the post office inside to perform those functions.
... confidence and he wanted him to join with him in the wrecking of the 'Lark.' My detective learned from 'Red Mike' that he planned to throw the 'Lark' into a ditch by placing a derailer on the track at a point in the hills a short distance from the city and to rob the mail car in the ... — Spring Street - A Story of Los Angeles • James H. Richardson