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 REPORT OF THE SECRETARY OF THE NAVY 
 
 C. S. Navy Department, 
 
 Richmond,. March 2Mu 1862. 
 
 Hon. Thomas S. Boco( k : 
 
 Speaker of the House of Representatives : 
 
 Sir: Incompliance with the resolution adopted by the 
 House of Representatives on the 18th instant, "that the 
 Secretary of the Navy he requested to make a report to this 
 House of the plan and construction of the Virginia, so far 
 as the same can be properly communicated, of the reasons 
 for applying the plan to the Merrimac, and also what per- 
 sons have rendered especial aid in designing and building 
 the ship," I have the honor to report that on the 10th day 
 • >f June, 1861, Lieut, John M. Brooke, C. S. Navy, was 
 directed to aid the Department in designing an iron-clad 
 war vessel, and framing the necessary specifications. 
 
 He entered upon this duty at once, and a few days thcre- 
 afier submitted to the Department, as the results of his in- 
 vestigations, rough drawings of a casematcd vessel with 
 submerged ends and inclined iron-plated sides. The ends 
 of the vessel and the eaves of the casemate, according to 
 his plan, were to be submerged two feet, and a light bul- 
 wark or false bow was designed to divide the water, and 
 prevent it from banking up on the forward part of the shield 
 with the vessel in motion, and also to serve as a tank to 
 regulate the ship's draft. 
 
 His design was approved by the Department, and a prac- 
 tical mechanic was brought from Norfolk to aid in prepar- 
 ing the drawings and specifications. This mechanic aided 
 in the statement of details of timber, &c, but was unable to 
 make the drawings, and the Department then ordered Chief 
 Engineer Williamson, and Constructor Porter, from the 
 Navy Yard, Norfolk, to Richmond about the 23d of June. 
 
iltation on thi object gen rally, and to aid in 
 
 the work. 
 
 Constructor Potter brought and submitted the model of a 
 flat-bottomed light draft propellor, casemated battery with 
 inclined iron-covered Bides and ends, which is deposited in 
 the Department. Mr. Porter and Lieut. Brooke have adopt- 
 ed for their casemate a thickness of wood and iron and an 
 angle of inclination nearly identical. 
 
 .Mr. Williamson and Mr. Poller approved of the plan of 
 having submerged ends to obtain the requisite flotation and 
 invulnerability, and the Department adopted the design, and 
 a clean drawing was prepared by Mr. Porter < •!' Lieutenant 
 Brooke's plan, which that officer then filed with the Depart- 
 ment. 
 
 The steam frigate Merrimac had been burned and sunk, 
 and her engine greatly damaged by the enemy ; and the De- 
 partment directed Mr. "Williamson, Lieut. Brooke, and Mr. 
 Porter to consider and report upon the hest mode of making 
 her useful. The result of their investigations was their re- 
 commendation of the submerged ends and the inclined case- 
 mates for this vessel, which was adopted by the Department. 
 The following is the report upon the Merrimac : 
 
 Sir: "In obedience to your order, we have carefully ex- 
 amined and considered the various plans and propositions 
 for constructing a shot-proof steam battery, and respectfully 
 report that in our opinion the steam frigate Merrimao, which 
 is in such condition from the effects of fire, as to be useless 
 for any other purpose, without incurring a very heavy ex- 
 pense in her rebuilding, &c; can be made an efficient vessel 
 
 of that character mounting ( ) heavy guns, 
 
 # # # * * * 
 
 and from the further consideration that we cannot procure 
 a suitable engine and boilers 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 vc 
 in a short time. The bottom of the hull, hoilers, and hea\\ 
 and costly parts of the engine being but little injured, re- 
 duces 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 make 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 
 iron plating to cover the shield. 
 
 The plan to be adopted in the arrangement of the shield 
 for glancing shot, mounting guns, arranging the hull, &c, 
 and plating to be in accordance with the plan submitted for 
 the approval of s the Department." 
 
 We are, with much respect, 
 
 Your obedient servants, 
 
 WM. P. WILLIAMSON, 
 
 Chief Engineer C. S. N. 
 JNO. M. BROOKE, 
 
 Lieutenant C. S. N. 
 JNO. L. PORTER, 
 
 Naval Constructor. 
 
 Immediately upon the adoption of the plan, Mr. Porter* 
 ■was directed to proceed with the constructors duties. Mr. 
 Williamson was charged with the Engineer's Department, 
 and to Mr. Brooke was assigned the duties of attending to 
 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 Ord- 
 nance for the ship, with other details pertaining to Ordnance. 
 
 These gentlemen labored zealously and effectively in their 
 several departments. Mr. Porter cut the ship down, sub- 
 merged her ends, performed all the duties of constructor, 
 and originated all the interior arrangements, by which space 
 has been economised ; and he has exhibited ability, energy 
 and ingenuity. 
 
 Mr. Williamson thoroughly overhauled her engines, sup- 
 plied deficiencies, and repaired defects, and improved great- 
 ly 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 im- 
 portance in the construction of the ship, devised and pre- 
 pared the model and drawings of the ship's heavy Ordnance — 
 being guns of a class never before made, and of extraordi- 
 nary 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 con- 
 
struction, which were experimentally determined, are neces- 
 sarily omitted. 
 
 The novel plan of Bnbmerging the en^a of the ship, ami 
 the eaves of the casemate, however^ is the peculiar and dis- 
 tinctive feature of the Virginia. It was never before 
 adopted. 
 
 The resistance of iron plates to heavy Ordnance, whether 
 presented in vertical planea or at low angles of inclination, 
 had bees investigated in England before the Virginia was 
 commenced; ami Major Barnard, U. 8. A., had referred to 
 the subject in his " Sea-coasi Defences. 
 
 We were without accurate data, however, and were com- 
 pelled to determine the inclination of the plates and their 
 thickness and form by actual experiment. 
 
 The Department has freely cunsultcd the three excellent 
 officers referred to, throughout the labors on the Virginia, 
 and they have all exhibited signal ability, energy am! . 
 I have the honor to be. 
 
 Very respectfully. 
 
 Your ob't servant. 
 S. R. MALLORY, 
 Secretary of the Navy, 
 
Hollinger Corp. 
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