606 



NAVY, UNITED STATES. 



Kinburn, in the subject of iron armor ; and, in 

 experiments in which 50-lb. balls were fired at 

 several yards' distance, and with a heavy charge 

 of powder, upon plates of the thickness alrea- 

 dy adopted, it was found that the balls sufficed 

 to break the plates, though they did not go 

 through them. The results, however, differed 

 much with differences in quality of the iron; 

 and, if not previously admitted, it now became 

 evident that, for resistance to shot, a some- 

 what soft iron is preferable to ?.n iron having 

 great hardness, with its attendant brittleness. 

 The experiments undertaken in the United 

 States had tended to show that, for guns of 

 the largest caliber then in use, although 44- 

 inch plates, well backed with solid timber, 

 were likely, for a time, to resist piercing by 

 shot thrown from considerable distances, yet 

 nothing less than 6 inches of iron plating could 

 be relied on to render a ship practically 

 invulnerable. This result was discouraging, in 

 view of the fact that the complete armoring of 

 a ship with 6-inch plates appeared to involve a 

 weight which no vessel can carry without 

 great sacrifice of speed, and a loss even of ca- 

 pacity for open-sea service. 



The next step in the construction of iron-clad 

 ships (French, raisseaux en cuirass, or navires 

 cuirasses), was the building of La Gloire in 

 France (I860), and of the Warrior in England 

 (1861). The armor of these ships is described 

 in the preceding volume of this CYCLOPAEDIA. 

 Sir Howard Douglas has lately asserted in sub- 

 stance that both these ships are failures, so far 

 as sea-going qualities, speed, and the stability 

 requisite for successful firing upon a heavy sea, 

 are concerned. Both appear to be, with com- 

 bined armament and armor, overloaded, and 

 owing to the lowering, in consequence, of the 

 meta-centre (centre of pressure of the liquid dis- 

 placed) to near the place of the centre of grav- 

 ity, both these ships roll in a heavy sea with 

 quick and considerable movements, so that the 

 gunner's aim in such cases becomes extremely 

 uncertain. Moreover, while La Gloire has not 

 exceeded 11, in place of the 13^ knots an hour 

 anticipated, and the "Warrior at sea not more 

 than 12, the latter can carry but 9 days' coal, 

 and in long voyages must often rely on tenders 

 or sails. Apparently, therefore, these ships, 

 and, probably, the others armored by the two 

 nations upon respectively the same patterns, 

 are not, on the score of their capacity for dis- 

 tant expeditions and aggressive warfare, very 

 greatly to be dreaded. 



The Revolving Turret, or Cupola. But 

 while ships may possibly be so armored as to 

 be in the main nearly impregnable to an en- 

 emy's fire, yet their portholes remain subject to 

 the entrance of shot, and that in proportion to 

 the size that must be allowed for properly work- 

 ing and pointing the guns; while the lateral 

 sweep in this way secured is always limited, 

 and the entire ship must often be manoauvred 

 in order to bring the guns into the desired line. 

 If, however, instead* of the ordinary casemate 



or broadside arrangement, the guns can be 

 placed within a protecting structure which can 

 be revolved into any required line of fire, all 

 the difficulties connected with the management 

 of the guns, the exposure incident, and the con- 

 tinual effectiveness of the ship's armament, van- 

 ish or are reduced to their minimum. Such 

 is the idea of the revolving turret or cupola, 

 and such the objects to be attained through its 

 use. The original invention of this important 

 addition of the last few years to the means of 

 naval warfare, has already been claimed on be- 

 half of three persons, Capt. John Ericsson of 

 New York city, Mr. Theodore E. Timby, of the 

 State of New York, and Capt. Coles, of the 

 British navy. In the year 1854, Capt. Erics- 

 son forwarded from New York to the emperor 

 Napoleon a communication (dated Sept. 26) 

 in reference to a new form of armored vessel 

 for naval attack, designed by him the plan 

 embodying many of the features of the " Mon- 

 itor," presently to be referred to, but especially 

 those of a deck rising but a few inches out of 

 water, and of a turret amidships to contain one 

 or two large pieces of ordnance, and to be ca- 

 pable of being revolved so as to bring the guns 

 into any desired line of fire : the shape of this 

 turret, however, was that of a dome, or half a 

 hollow globe, the ports being at one side. The 

 receipt of the communication was duly ac- 

 knowledged by the emperor. Capt. Erics- 

 son further states that the idea of a revolving 

 tower for ordnance upon land is very old ; but 

 that the thought of placing such a structure 

 upon a ship was original with himself, having 

 been conceived many years before the time of 

 the communication above mentioned. Capt. 

 Coles, in a letter to the (London) " Times," 

 April 5, 1862, states that the idea of building 

 impregnable vessels was suggested to him by 

 his experience in the Baltic and Black seas, in 

 1855, and that toward the close of that year he 

 had a model for such vessels made, in which 

 he proposed to protect the gnns by a stationary 

 "shield" or "cupola." Notwithstanding offi- 

 cial neglect, he persevered, producing in March, 

 1859, drawings of a "shield fitted with turn- 

 tables ;" and in December, 1860, he published 

 an account, with drawings, in which the plat- 

 form of the shield was to be turned by manual 

 power. Mr. Timby constructed, in 1841, a 

 model of a revolving tower for land fortifica- 

 tions, pierced with one or two tiers of port- 

 holes, and to contain several gnns, these to be 

 fired in succession as they were brought by the 

 revolution in line with the object of attack. A 

 larger model was exhibited in many places in 

 1843, among others in New York, notices of it 

 appearing in the "Evening Post" of June 13, 

 of th,at year, and in the " Herald," during the 

 same month. It will be seen that the pur- 

 poses and principle, on the one hand, of the 

 Ericsson and Coles turrets (accounts of which 

 will be given farther on), and on the other, of 

 that of Mr. Timby, are wholly distinct : with 

 the former, the revolution of the tower is not 



