Until about 1967, the U.S. Postal Service used railroads to handle mail on designated routes in special Railway Post Office cars, which served as post offices on rails staffed by postal employees who sorted mail en route on moving trains. Sorted mail pouches were delivered at station stops or thrown off as trains passed, and where the amount of mail was too small to justify a stop, trains exchanged mail without slowing down through a method called mail-on-the-fly. In that process, a station agent placed mail in a heavy canvas catcher pouch and hoisted it to the arm of a mail crane beside the tracks for pickup. A mail route operated on the Atlantic & Danville corridor, probably through the 1940s when the Southern Railway ran passenger trains over the line, and mail handling over the A&D ended when the Southern Railway terminated passenger service in 1949.