r20 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



American Institute Polytechnic Association, ) 

 December 3, 1863. j 



S. D. Tillman, Esq., presiding-; Mr. B. Garvey, Secretary. 



New Slide Valve. 



Mr. E. A. L. Roberts exhibited a model of his new slide valve, and said: 

 It is somewhat difficult to explain without drawing-, and I should much pre- 

 fer to have a committee appointed to examine and report from a working 

 model which I have in use. It is a small engine, three and a half inches 

 in diameter and eight inches stroke, which does six times the work of a 

 cylinder of the same capacity with the ordinary valve, and this engine 

 works with greater regularity than any engine I have ever examined. I 

 have seen the steam pressure vary from 20 to 60 pounds, and there could 

 not be noticed more than two or three extra strokes. The valve is balanced, 

 and the shaft that lifts the valve is adjustable by the governor. 



On motion, this valve was referred to a committee consisting of Messrs. 

 Bartlett, Rowell and Fisher. 



New Repeating Gun. 



Mr. Kellogg, of Hartford, presented a working model of his gun and said: 

 The object in devising a gun of this kind was to produce an arm that would 

 outreach the range of infantry, and the longest reach of any known fire- 

 arm. The longest range we now have is from a half to five-eighths of a 

 mile, and my gun will carry further than that. On account of the shower 

 of balls that could be thrown at any desired point, I think it woulS not be 

 difficult to stop a field battery from firing all day. It is worked by simply 

 turning a lever back and forth. The cartridges are intended to be the same as 

 those I have here, which are four and three-eighths inches long, and sixty-four 

 hundredths in diameter. I have fired this 800 times as rapidly as I could, 

 and only stopped when I found the barrel got so hot that I feared it would 

 burst. The weig-ht of the gun mounted on wheels will be about 300 pounds, 

 and the balls will weigh, cartridges and all, about five ounces. There are 

 two barrels which can be used alternately, so that one can be cooling while 

 the other is being fired; but I may say that very rapid firing is seldom 

 found necessary. The cartridges are metallic, and the fulminate is in the 

 end, so that it requires no cap. The objection that I have heard to guna 

 that fire rapidly, is that they waste ammunition, and that only a few shots 

 can be effective, as after a volley the smoke obscures everything, and then 

 firing is at random. This is no doubt true, but with my gun there need be 

 no rapid firing any more than with the ordinary rifle, and we can wait until 

 an oltject appears to fire at, and when necessary we can make this gun, 

 with the aid of two men, equal to the firing of a whole regiment. 



Mr. T. D. Stetson. — Why would you not make your guns of a larger size, 

 that is increase the bore so as to make the shots more destructive ? 



Mr. Kellogg. — To do so would be only making what we now have. 

 There are cannon now in use of one inch and one and a half inches in the 

 bore. My gun is intended to take the place of light artillery. 



Mr. Stetson. — The Union gun, made somewhat on this style, was a re- 

 volver mounted on wheels, arjd could be moved about like light artillery, and 



