...eal to the Federal vessels, should they attempt to enter. Nearly west of Sumter, on James' Island, was Fort Johnson, where a strong battery of mortars and cannon was erected. On the northeast was Fort Moultrie , ready with Columbiads, Dahlgren guns, mortars, and furnaces for red-hot shot. In the cove near the western end of Sullivan's Island, was anchored a floating battery, constructed of the peculiarly ...