Gunter’s chain was a measuring device used for land surveying. It was designed in 1620 by English clergyman and mathematician Edmund Gunter. Gunter’s chain is divided into 100 links, each link being 7.92 inches long. A chain is 66 feet in length. One quarter of a chain (16.5 feet) is called a rod or a pole. An acre is 10 square chains. U.S. Public Land Survey plats are still published showing chained units.
Until after 1900, most lines were measured with Gunter’s link chain.