Boiler iron off a blockade runner
Unable to keep the hides lining his sandbag embrasures from being blown apart by the guns, Brooks sent a squad to strip plates of sheet and boiler iron from the wreck of the blockade runner Ruby, ashore on Morris Island. The Federal siege works were partly built out of the ships that had been trying to supply Charleston.
Major Brooks’ journal, OR I, 28, Pt. 1