496 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



State of Missouri, City of St. Louis, ss : Aloxaridor Kilpatrick bein<^ duly 

 Bworn according to law, doth depose and say, that he was on the United 

 States gunboat Choctaw, on the 30th day of April, 1863, in her engage- 

 ment with the enemies batteries on the Yazoo river ; that a portion of the 

 casemates on said vessel was on the plan invented and placed on her by 

 J. L. Jones, of the city of St. Louis, and Commodore Wm. D. Porter of the 

 United States Navy, and were provided and placed on the said vessel by 

 the same; that such portions of said casemates, were covered according to 

 such plan with gum elastic cushions, and a portion, not so covered with 

 such gum elastic, it penetrated and destroyed the same. And when a shot 

 struck a part so covered, it simply dented the iron and rebounded upon the 

 deck and exploded, doing little or no damage to the deck ; and deponent 

 further saith, that this and the statement signed by him dated Haines 

 Bhiff, April 30th, 1863, are and each of them is true to the knowledge of 

 deponent. ALEXANDER KILPATRICK. 



Sworn before me, this 28th day of July, 1863. 



Benjamin F. Hickman, U. S. Com., Mo. Dist. 



Commodore Porter. — In corroboration of Mr. Jones' remarks, I will now 

 submit the following statements of actual experiments made on our 

 western waters the results of which strongly indicate that it is practicable 

 to unite impenetrability with buoyancy. 



Plate Armor for Sea-Going Vessels, Uniting Buoyancy with 



Impenetrability. 



With reference to this subject it is known that hard, solid, and ponder- 

 ous substances, as well as those of a soft, light, fibi-ous, or elastic nature, 

 (when the fibres are interlocked by compression,) will successfully resist 

 the penetration of projectiles, the former substances operate by opposing 

 direct resistance ; the latter, by the elasticity of the mass, gradually 

 checks the force, and by the power of adhesion and reaction, enlarges the 

 base of resistance round the point of impact, consequently diffuses the 

 force of the shot over a greater extent of surface ; and a cannon ball, when 

 projected with great velocity, has both weight and impetus, or "vis viva." 

 Theoretically, therefore, it would seem, that a combination of both the 

 above mentioned powers and principles of resistance to penetration, would 

 not only be effectual, but at the same time admit of that buoyancy so 

 essential in sea-going vessels ; and for the purpose of fully availing our- 

 selves of both these principles of resistance, it is proposed to employ a 

 series of iron and vulcanized India rubber plates, alternately arranged, as 

 shown by the accompanying drawings ; for it is manifest that the force of 

 the blow will thereby be diflfused from the point of contact, over a larger 

 extent of the surface of the inner plates, and therefore enlarge the base of 

 resistance to the penetration of the superior plate. 



The correctness of the above theory was inferred from the well-knowu 

 action of India rubber, when vulcanized and combined with metallic sub- 

 stances, or fibrous tissues, and from the analogous action of all vegetable 

 and metallic fibres when free to act. In order to test the correctness of 

 some of the principles above suggested, as far as practicable at the time, 



