MAJOR BROOKS' JOURNAL OF ENGINEER OPERATIONS EXECUTED UNDER HIS DIRECTION ON MORRIS ISLAND, BETWEEN JULY 12 AND SEPTEMBER 7, 1863.
The batteries employed in the bombardment of Fort Wagner on the 18th of July were in two lines.
The advanced line, 1,350 yards from the fort, formed the right wing, and was commenced on the evening of July 12, on the site selected by the general commanding. This line was afterward designated the first parallel of the siege. Its center is 285 yards N. by E. from the Beacon House. I superintended the opening of this parallel, and was relieved about midnight by Colonel E. W. Serrell, New York Volunteer Engineers, who had the direction of the work. I also had charge of this work the first half of the night of July 13, and was again relieved by Colonel Serrell.
The second line, or the left batteries, was built on a narrow peninsula hummock, which projects westward into the march from Morris Island proper. This retired line is 1,830 yards from Fort Wagner, and about 400 yards to the left of the first line.
I received the order to begin the construction of the left batteries about noon, July 14, 1863.
Tuesday, July 14.-Began, on site of what appeared to be an unfinished defensive work of the enemy, excavations for the emplacements and magazine for four 10-inch siege mortars, which will constitute the right wing of Battery O'Rorke.
Wednesday, July 15.-Continued work on Battery O'Rorke.
Began and completed positions for four 30-pounder Parrott rifles, being the left guns of Battery Hays, which is 110 yards in advance of Battery O'Rorke, and 1,830 yards from Fort Wagner.
The ordnance corps mounted one 10-inch siege mortar in Battery O'Rorke, being the first piece placed in position against Fort Wagner.
Lieutenant James E. Wilson, U. S. Artillery, under the direction of Lieutenant C. R. Suter, U. S. Engineers, assistant engineer, Department of the South, had charge of the construction of the left wing of Battery O'Rorke, afterward called Battery Kirby. Emplacement and a bomb-proof service magazine were prepared for four 10-inch siege mortars. Only one was mounted until after the 18th instant, when two 10-inch seacoast mortars were added; these were used against Fort Sumter in the first bombardment.
Thursday, July 16.-Completed the right wing of Battery O'Rorke, including a splinter-proof service magazine. The mortar platforms in this battery consisted of four 3-inch by 10-inch sills covered with ordnance deck plank well spiked down. They failed after six hours' firing.* The interior slope of the parapet of the battery was revetted with one thickness of sand-bags 4 feet high.+
Emplacements were also completed for three additional 30-pounder Parrott rifles, making the seven which constituted the left wing of Battery Hays. Five were in embrasure, and two, on the extreme left, en barbette. The latter were arranged to be used against the enemy's boats in the south part of Charleston Harbor and Light-House Creek, as well as against Fort Wagner.
Began, in the right wing of Battery Hays, emplacements for four 20-pounder Parrott rifles. The platforms of these pieces are 8 feet square, built of light plank, laid on five sills, the center one running far enough to the rear to support the trail of the piece.
*See Note 11, following journal, p. 319.
+See Note 10, p. 318.