MECHANICS AND USEFUL ARTS. 91 



ing that port open and exposed to the hostile fire. Her rudder chains 

 were also a most serious element of weakness with her, being carried 

 along her deck, and covered only with a plate of half-inch iron. They 

 were, consequently, broken early in the engagement, and her rudder 

 was subsequently managed by means of ropes and blocks, and yet- 

 notwithstanding all these injuries, the commission of oiliccrs that sur- 

 Tcyed the Tennessee, immediately after the fight, reported her " in a 

 condition to do good service, 1 ' and although captured, her resistance 

 is a matter of great interest and importance in the new developments 

 concerning naval warfare, and furnishes new testimony to the value of 

 iron-clad vessels. 



The London Times, in commenting upon this extraordinary trial, 

 draws this conclusion ; either the armor of the Tennessee was supe- 

 rior to any of the targets which represent our British iron clads, or the 

 ordnance of the Federals is inferior to our artillery. We have already 

 said that we do not think the former hypothesis could be maintained 

 for a moment, and, consequently, we must close with the latter. This 

 we do without hesitation, and we imagine that most persons acquainted 

 with the subject would be prepared to affirm that the guns which pen- 

 etrated the Warrior target, at Shoeburyness, would, at ten feet dis- 

 tance, have smashed in the sides of the Tennessee before the action had 

 lasted a quarter of an hour. 



Iron-clad Vessels. The Ironsides and Monitors contrasted. The 

 following is the substance of a Roport recently made to the Secretary 

 of the Navy by Commodore John Rodgers on the comparative merits 

 of the Ironsides and Monitor class of vessels. 



These vessels have each their peculiar defects and advantages. 



In the ironsides class the hull of a wooden man-of-war, as con- 

 structed for general purposes, is clad with iron. It is true, some 

 modification of shape and increase of size is required to meet the ad- 

 ditional weight which she has to carry, but still in essentials she is a 

 vessel of the ordinary model ; she has the advantage of ample quar- 

 ters for her crew, with free access to her deck in storms ; with natural 

 ventilation; with abundance of light; with numerous guns, giving 

 her a rapidity of fire unattainable in a monitor, and essential in bat- 

 tering forts ; and she is as able to carry canvas as other men-of-war. 



The monitor class, as far as I know, is new. If I understand the 

 idea, it is to cut off all the surface above the water except that which 

 may be necessary to flotation, and to carry the guns in a revolving 

 turret, or turrets, near the center of motion, supported upon the keel 

 and kelsons. 



The plans upon which Mr. Ericsson has worked out this idea of 

 his may be modified by further experience, but the idea itself will be 

 employed while iron-clad vessels are used in warfare. 

 It lias these advantages : 



The monitor has the least possible surface to be plated, and there- 

 fore takes the least possible tonnage to float armor of a given thick- 

 ness ; or with a given tonnage allows the greatest possible thickness 

 of armor, and consequently the greatest possible impenetrability. 

 The ability to carry armor is proportionate to the tonnage, but the 

 monitor of 8i-l tons has actually thicker plating than the ironsides of 



