As applied to the post-otfice, this term means the carriage of letters, whether applied to the hag into which they are put. the coach or vehicle by means of which they are transported, or any other means employed for their carriage and delivery by public authority. Wynen v. Schappert, 6 Daly (N. Y.) 560. It may also denote the letters or other matter so carried. The term “mall.” as used in Rev. St. U. S.