led the owners to send prospectors into the surrounding countryside. In 1658 the company bought of land which covered areas that are now Concord, Acton, and Sudbury. They set up a large production facility in Concord, Massachusetts, along the Assabet River with dams, ponds, watercourses, and hearths, but by 1694 the natural bog iron there had also been exhausted, and the land was sold for farming. In Central and Southern New Jersey, bog ore was mined and refined for the production of naturally rust-resistant tools and wrought iron rails, many of which still grace staircases in Trenton and Camden. During the American Revolution, bog iron cannonballs were cast for the colonial forces. 19th century United States Bog iron was also found on the Eastern Shore of Maryland. The remains of a commercial smelting operation near Snow Hill, Maryland, are now a state and national historic site. Known as Furnace Town, it was called the Nassawango Iron Furnace after the nearby creek. The commercial furnace ran from about 1825 to 1850. The Shapleigh Iron Company constructed a smelter at North Shapleigh, Maine, in 1836 to exploit a small bog iron deposit in Little Ossipee Pond. The plant commenced operation in 1837, but according to an 1854 history of Shapleigh "the business [proved] unprofitable, therefore after a few years it was abandoned." See also (iron-oxidizing bacteria) References External links ASME PDF file with detailed reconstruction drawings of the furnace and surroundings. at the Maryland Historic Trust. Bogs Iron Economic geology Iron ores fi:Järvimalmi