522 MEMOIR OF DANIEL TKEADWELL. 



present at all the sessions to appreciate the extreme certaint3- to which it had been carried at each 

 round. The pointing was made with less precision, and more rapidly, than in the series devoted to this 

 particular object; nevertheless the mean number of these hits was much greater than that of the howit- 

 zer of the Schools. The accuracy of the firing was simply a consequence of tlie perfect condition in 

 ■which the whole bore is constantlj- maintained. It is this result which has especialh- fixed the attention 

 of the commission. The successive verifications after each 50 rounds (by placing tlie gun on end and 

 filling it to the face with water and hermetically closing it with a greased plug) indicated no change 

 of diameter. There was not the least lodgment of the ball, nor beating (battement) ; as to certain 

 variations iu diameter they were ver3- slight, and, not being repeated in successive verifications, they are 

 not to be regarded. With the mirror and a bright sun the piece was well examined ; not the least 

 traces could be seen of beating, scraping, or degradation, even at the bottom of the chamber. 



One circumstance remains to be pointed out, and that is the inconvenience of the great recoil of 

 the gun. AVe ought to expect it, especiallv in the firing of the last series with charges of 2 kilo. 700 

 and a ball of 30 (32 English) in a piece which is but fifty -seven times the weight of the projectile. But 

 it exceeded our expectations. The arrangements made did not prevent it from often running off the 

 platform. It was also observed that the gun drooped much in the chase at each fire {saiffiiait forte- 

 ment du nez). 



To recapitulate. The gun has borne this first proof, not only without the accidents we might 

 legitimately expect from what usually occurs with iron guns, but also without those we might fear fi-om 

 the two peculiarities of its construction, viz.: 1st, the bottom of the chamber formed by a pin 

 screwed into the breech ; 2d, the trunnions fixed to the gun by a hoop screwed on and riveted. The 

 breech pin, after being slightly unscrewed at the 147th round, was again screwed up, and never moved 

 again ; the gases did not injure the bottom of the chamber (there was ver}' little escape of gas from 

 the 4th session of firing). The trunnion hoops are in precisely the same condition as at the commence- 

 ment of the firing. One of the small rivets or splines which appeared to fasten it was only slightly 

 started at the last session. We may say, then, that the gun has borne this proof well, and appears to be 

 iu a condition to bear others still more severe. 



Mr. Treadwell's principal object is the solution of the problem of lightening the armament of 

 vessels without diminishing their force, that is to say, without diminishing the calibre of the guns. For 

 this purpose he has endeavored to unite with a very light gun excessive strength or tenacity and hard- 

 ness of metal, which will admit of the prolonged use of large calibres and high charges. Besides, he 

 proposes a powerful and simple means for stopping the recoil on ships. He may then have a happj' 

 application of his improvements in the manufacture of iron cannon. Besides, if we could always obtain 

 an accuracy of fire as remarkable and valuable as that of the cannon now under proof, should we not 

 have reason to anticipate great advantages for field artiller}- without too gi'eat inconveniences? 



It should be assured further that we can protect these pieces from rust, which acts more, and more 

 constantlv, on iron and steel than on bronze. These olijections removed, it ma\- be but a question of 

 cost between these guns and those of bronze. The author has not informed us as to this important point 

 in the manufacture. In view of the results obtained in this first proof, so well calculated to stimulate 

 curiosit}- as to the limit of resistance of iron and steel thus wrought and welded, the commission is 

 unanimously of opinion that the gun now under trial should be submitted to further proof. 



Signe, Brafve, Lefrakcaise. de Trton {Cap"' ^Rapporteur) , 



Brady, Ladraxge. 



Pour copie conforme, Le Chef de Escadron President, 



Signe, BKArvE. 



ViscExsEs, IS Mar, 1848. 



