Southern Historical Society Papers, Volume 20.
Reverend J. William Jones, Ed.

1. ‘That on June 10, 1862, Lieutenant John M. Brooke was directed to aid the Navy Department in designing an ironclad, and to frame the necessary specifications.’

2. ‘That in a few days he submitted rough drawings of a casemated vessel with submerged ends, and inclined iron-plated sides, which was approved by the department.’

3. ‘That Chief Engineer Williamson and Constructor Porter were ordered to report in Richmond about the 23d of June for consultation on the same subject generally, and to aid in the work.’

4. ‘That Mr. Williamson and Mr. Porter approved the plan of having submerged ends to obtain flotation and invulnerability, and a clean drawing was prepared by Mr. Porter of Lieutenant Brooke's plan, which that officer then filed with the department.’

5. ‘That the novel plan of submerging the ends of the ship and eaves of the casemate is the peculiar and distinctive feature of the Virginia, and was never before adopted.’

6. ‘That Mr. Williamson, Lieutenant Brooke, and Mr. Porter reported that the Merrimac could be utilized for this purpose, and recommended the submerged ends and inclined casement for this vessel, which was adopted.’

Lieutenant Brooke claims that the material feature of his plan is that the bow and stern shall each extend under water beyond the forward and after ends of the shield or casemate, to give the sharpness for speed and buoyancy to support the weight of iron; and a patent for this claim was duly issued to Lieutenant John M. Brooke, by the Confederate Government, July 29, 1862.