Odometer by American Taximeter Company
The upper third of the metal casing houses the mechanism to measure distance traveled. The hollow, lower two-thirds of the cylinder attaches the odometer to the vehicle and is secured with three screws. The face consists of four small windows displaying numerals; the unit of measurement is not specified.
The Post Office Department equipped route agents with odometers to establish rural free delivery routes in the late nineteenth and early twentieth centuries. Using odometer readings and maps, officials worked to optimize the routes in new areas. They sought to use the minimum number of carriers and to portion the routes into equal distances. Some carriers used odometers to argue for changes to their routes, recording their miles covered and hoping to prove that an alternate road could save time.