The Post Office Department published specifications and construction plans for the wagons that gave these urban routes their name—Regulation Wagon Service—in 1879. A lighter wagon with screen sides to hold the mailbags and tarps for protection against inclement weather then became the standard vehicle for the mail messenger service. By 1895 there were regulation wagon contracts in thirty-seven cities and screen wagon contracts in forty-three more, plus forty-eight cities employing mail messenger screen wagons without contracts.
That horse-drawn wagons plodded through congested streets to meet the fast trains of the Railway Mail Service troubled Postmaster General John Wanamaker. In 1889 he set a goal to "secure transit for mail on faster schedules; provide quicker collections and distributions in cities and towns by pneumatic tubes or other improved and more rapid couriers than now exist; push forward American mails as the forerunner of the extension of American commerce; lift the entire service into a larger usefulness for the people." The next decade saw experiments to improve intra-city collection and distribution using streetcars, pneumatic tubes, improved wagons, and the horseless wagon. Within three decades motorized postal trucks became the dominant form of intra-city mail transportation.
St. Louis postmaster John Harlow began operating a Railway Post Office (RPO) streetcar over the tracks of the St. Louis and Suburban Railway on December 5, 1892. At the same time, John Wanamaker inaugurated a half-mile experimental pneumatic tube to carry mail between the East Chestnut branch and the main Philadelphia Post Office on February 17, 1893. Networks of pneumatic tubes, totaling over fifty-six miles, collected and distributed mail in six cities by the time Congress terminated funding in 1918. RPO service ended in most cities then too. Although once utilized in fifteen cities, by 1917 streetcar RPO service remained only in Cleveland, Omaha, and Baltimore. Owing to congested streets, the pneumatic tube system was restored in Boston and New York during the 1920s and was used in New York until the 1950s.
In a last attempt to improve wagon service, the regulation and screen wagon services were consolidated under a single budget in 1896, and Collection and Distribution Wagons were introduced. Modeled after RPO cars, these large, horse-drawn wagons with space for clerks to process mail rolled down the streets of Washington, D.C., and New York on October 1, 1896. After additional tests in Buffalo and St. Louis, the service ceased in 1904.
While the 1896 Annual Report spoke of "experiments with the horseless wagons," the initial test of a Winston motor wagon to collect mail did not occur until a snowy week in Cleveland during December 1899. The St. Louis postmaster soon replaced his Collection and Distribution Wagons with automobiles, which were used to great advantage at the 1904 Louisiana Purchase Exposition. From the first automobile contract in Baltimore, October 1, 1906, the use of motor vehicles grew quickly. By 1921 the Post Office Department had standardized eight types of trucks. In 1929 the last streetcar RPO service ceased in Baltimore. The victory for motor vehicles was complete when the New York pneumatic tube ceased operation on December 31, 1953, and the last Philadelphia horse wagon retired January 31, 1955.
David L. Straight