Odometers were developed for ships in 1698 with the odometer invented by the Englishman Thomas Savery. Benjamin Franklin, U.S. statesman and the first Postmaster General, built a prototype odometer in 1775 that he attached to his carriage to help measure the mileage of postal routes. In 1847, William Clayton, a Mormon pioneer, invented the "Roadometer", which he attached to a wagon used by American settlers heading west. The "Roadometer" recorded the distance traveled each day by the wagon trains. The Roadometer used two gears and was an early example of an odometer with pascaline-style gears in actual use.