122 ANNUAL OF SCIENTIFIC DISCOVERY. 



were severe, but only such as would fairly represent the contin- 

 gencies of actual service. A description of each arm is given, 

 and a full record of its endurance under the several tests. 

 The arms are divided into 5 distinct classes or systems, based 

 upon the attachment and movement of the breech-block, as fol- 

 lows : 



First Class. The breech-block hinged to front or rear of 

 receiver, and moving in a plane parallel to the axis of the barrel, 

 in which are included the Allin, Berdan, Hubbell, Joslyn's swing- 

 breech, Lampson, Milbank and Montstorm, all adapted to conver- 

 sion of muzzle loaders. 



Second Class. The breech-block hinged to the left-hand side of 

 receiver, and moving in a plane at right angles to the axis of the 

 barrel, including the Empire No. 1 and the Joslyn's cap, both 

 adapted to conversions. 



Third Class. The breech-block moving on a pivot at its 

 rear end, and the forward end dropping in the receiver, below 

 the chamber, for insertion of cartridge, including the Roberts, 

 adapted to conversions, and the Peabody, intended for original 

 arms. 



Fourth Class. The breech-block pivoted at its lower front por- 

 tion, near the front of receiver, and below the level of chamber; 

 revolving in a vertical plane passing through axis of barrel, falling 

 back to open the chamber and forward to close it, including the 

 Miller, Poultney, Remington, and the Robertson and Simpson, all 

 intended for original arms. 



Fifth Class. The breech-block sliding in the receiver, either 

 horizontally or vertically, including the Gray and the Meigs, both 

 adapted to conversions, and the Ballard, National, and Sharps, 

 intended for original arms. 



In addition to which classification is the Empire No. 2, having 

 no movable breech-block, the motion being in the barrel. 



The magazine guns examined were the Ball's, Gray's, and 

 Spencer's. The board arrives at twelve general conclusions or 

 points, based upon its experiments, which may be briefly stated 

 thus : 



1. That arms in classes first and second may be objected to, as 

 having too extensive movement of breech-block ; and, furthermore, 

 that it is an undecided question whether the hinge attachment is 

 sufficiently stable. 



2. That breech-blocks hinged as in classes first and second re- 

 quire an independent locking device. 



3. That breech-blocks hinged as in class second, on the left- 

 hand side, are awkward to manipulate. 



4. That arms of the third class, having lever above the stock, 

 are objectionable on account of constrained action in operating 

 them. 



5. That large sliding surfaces, as generally used in the fifth 

 class, are objectionable on account of the friction, etc. 



6. That any movement of the barrel, relative to the stock, is a 

 source of weakness. 



7. That extensive lever movement in any arm is objectionable. 



