Seven heavy platforms in the second parallel
The last heavy gun platform in the second parallel was laid — seven in all: two 8-inch Parrott rifles in Battery Brown and five 100-pounder Parrotts in Batteries Rosecrans and Meade. These were the guns that would breach Fort Sumter from four thousand yards, a range at which nobody had ever breached masonry before.
Major Brooks’ journal, OR I, 28, Pt. 1