Lieutenant Colonel Jonathan Williams, placed in charge of New York Harbor defenses in the early 1800s, proposed several new fortifications around the harbor as part of the Second System of fortifications. Unlike the First System defenses, the new fortifications were to be made of masonry to preclude deterioration, and they included increased firepower and improved weaponry. Fort Jay was rebuilt from 1806 to 1809 in its current five-pointed star shape, and was renamed Fort Columbus shortly afterward. A second major fortification, Castle Williams, was a circular battery built between 1807 and 1811 on a rocky shoal extending from the northwest corner of the island, to the north of Fort Columbus. A third fortification, the South Battery or Half-Moon Battery (now building 298), was built to the south of Fort Columbus on the island's eastern shore in 1812. The War of 1812 commenced shortly after the completion of these defenses, though the fortifications never saw combat.