proceedings of the polytechnic association. 665 



American Institute, Polytechnic Association, ) 

 Jpril 18, 1861. \ 



Professor Mason in the chair. 



projectiles and naval warfare. 

 Capt. Washington A. Bartlett. — The reports of the proceedings 

 of the Association on projectiles has attracted much attention. 

 I wish to read a communication which will give some important 

 information. 



james' projectiles. 



New York, Jpril 13th, 1861. 

 To the Editor of The Century:— 



Dear Sir: At the weekly sittings of the " Polytechnic Associa- 

 tion of the American Institute," of Thursday evening, March 

 28th, and Wednesday, April 3d, the subject of steel plated ships, 

 or iron cased floating batteries was discussed by myself and 

 others, of which you give a report in your issue of this date, ex- 

 tracted from the report in the " Scientific American." The sub- 

 ject of steel plated or iron cased ships and batteries, necessarily 

 involves the highest perfection and power in destructiveness of 

 projectiles; and hence the topic of explosive shells, solid shot, 

 Stevens' shells, the combined shot and shell ; and the last inven- 

 tion in cannon projectiles, destined, as I believe, to take the 

 place of all, or nearly all, the common or bomb projectiles now 

 in use, (and to which you adverted in an editorial article in No. 

 115 (March 2d) of The Century,) viz : the "GeneralJames Rifled 

 Cannon and Projectiles," become of necessity a part of the dis- 

 cussion, intended — as are all the statements, discussions or re- 

 marks, made at the meetings of this enlightened body in the 

 American Institute, — for the purpose of eliciting facts, and 

 demonstrating the practical working of old or new theories ; 

 hence of great interest to the public, who, as a member of the 

 Institute, I can assure you, are ever welcome to its sittings as a 

 Polytechnic Association. 



These reports in the Scientiflc American and the Century are 

 attracting much attention ; and having received to-day from 

 General James himself, a communication on the subject, together 

 with a set of the photographic plates, taken on the ground at 

 the time of the trial shooting, with a sketch of the shot, the 

 battery, the targets, and the results of the shooting, which were 

 reported to the Department of War ; I have determined to bring 



