. . . heavy guns, and from the further consideration that we cannot procure a suitable engine and boiler for any other vessel, without building them, which would occupy too much time, it would appear that this is our only chance to get a suitable vessel in a short time. The bottom of the hull, boilers and heavy and costly parts of the engine being but little injured, reduce the cost of construction to about one third of the amount which would be required to construct such a vessel anew. We cannot, without further examination, maker an accurate estimate of the cost of the proposed work, but think it will be about . . . . the most of which will be for labor, the materials being nearly all in the navy-yard, except the ironplating to cover the shield. The plan to be adopted in the arrangement of the shield for glancing shot, mounting guns, arranging the hull, etc., and plating, to be in accordance with the plan submitted for the approval of the department. We are, with much respect, your obedient servants,
Immediately upon the adoption of the plan, Porter was directed to proceed with the constructor's duties. Mr. Williamson was charged with the engineer's department, and to Mr. Brooke were assigned the duties of attending to and preparing the iron and forwarding it from the Tredegar Works, the experiments necessary to test the plates and to determine their thickness, and devising heavy rifled ordnance for the ship, with the details pertaining to ordnance. Mr. Porter cut the ship down, submerged her ends, performed all the duties of constructor, and originated all the interior arrangements by which space has been economized, and he has exhibited energy, ability and ingenuity. Mr. Williamson thoroughly overhauled her engines, supplied deficiencies, and repaired defects, and improved greatly the motive power of the vessel. Mr. Brooke attended daily to the iron, constructed targets, ascertained by actual tests the resistance offered by inclined planes of iron to heavy ordnance, and determined interesting and important facts in connection therewith, and which were of great importance in the construction of the ship; devised and prepared the models and drawings of the ship's heavy ordnance, being guns of a class never before made, and of extraordinary power and strength. It is deemed inexpedient to state the angle of inclination, the character of the plates upon the ship, the manner of preparing them, or the number, calibre, and weight of the guns; and many novel and interesting features of her construction, which were experimentally determined, are necessarily omitted. The novel plan of submerging the ends of the ship and the eaves of the casemate, however, is the peculiar and distinctive feature of the Virginia. It was never before adopted. The resistance of iron plates to heavy ordnance, whether presented in vertical planes or at low angles of inclination, had been investigated in England before the Virginia was commenced, and Major Barnard, U. S. A., had referred to the subject in his “Sea-Coast defences.” We were without accurate data, however, and were compelled to determine the inclination of the plates, and their thickness and form, by actual experiment. The department has freely consulted the three excellent officers referred to throughout the labors on the Virginia, and they have all exhibited signal ability, energy, and zeal. I have the honor to be, very respectfully, Your obedient servant,
S. R. Mallory, Secretary of the Navy.