Report of Lieut. Cyrus B. Comstock, Corps of Engineers, U. S. Army, of Confederate works at Gloucester Point, Va.
CAMP WINFIELD SCOTT, NEAR YORKTOWN, VA.,
May 5, 1862.
SIR: In compliance with your instructions I have today visited  Gloucester Point, and submit the sketch (in atlas) on the next leaf of the rebel works there. These works are two in number, namely, a water battery on the extreme point, with its terre-plein only a foot or two above high tide, and a large field work on the bluff above. The water battery is U-shaped and has its rear closed. The guns and carriages were evidently navy ones; the parapet about 20 feet thick, and interior crest about 7 ½ feet high, revetted, and covered with turf embrasures, also revetted with sods. The main magazine, large and well covered with bomb-proof shelter, adjoining small magazines marked c and d and f on the sketch, (in atlas) shot furnaces a and b, and between each pair of embrasures an inclined bomb-proof blind, giving cover for the gunners. These blinds are made by leaning heavy timbers against the interior slope, where they rest on a frame also resting against the interior slope. These timbers are together about 3 feet thick, and are covered with sods. In the rear of the battery in a well by itself there is a barbette gun, c, the only gun now in the work. The whole work is carefully and neatly finished. There are embrasures for twelve guns.
The field work on the bluff is 30 or 40 feet above the water; is a bastioned work of strong but variable profile, the parapet varying from 15 to 20 feet in thickness, 7 to 10 feet in height, and a ditch from 7 to 15 feet in depth, the depth of ditch and height of interior crest varying with the inequalities of the level of the ground. Several of the magazines serve as traverses. A long line of bomb-proof shelter, giving a long traverse in the center of the work, had been begun. A well was in progress. In one place the parapet was not quite finished, and in another the revetment was incomplete. The masks to cover the outlet had not been finished up. The revetment, like that of the water battery, was of sods. The finished portion of the work was well and carefully done, with these exceptions. Guns and carriages were navy— these three were en barbette. There were no embrasures. The strength of the work is nearly the same as that of the work inclosing Yorktown.
C. B. COMSTOCK,
Lieutenant of Engineers
General J. G-. BARNARD,
Chief Engineer, Army Potomac Headquarters.
The caliber of several of the guns bearing on the river and on our positions is not given by Lieutenant Comstock. There were eight in all. Those not mentioned are believed to be as heavy as 32-pounders.
J. G. B.
Official Records of the Rebellion: Volume Eleven, Chapter 23, Part 1: Peninsular Campaign: Reports, pp.337-337
web page Rickard, J (4 February 2007), http://www.historyofwar.org/sources/acw/officialrecords/vol011chap023part1/02021_01.html