MECHANICS AND USEFUL ARTS. 91 



saturated with grease, lard, or tallow. The powder is between this 

 wad and the bullet, and after the discharge the wad remains in the 

 gun. Of course the wad goes out before the next bullet, and as the 

 gun grows warm by firing, the grease melts, and the gun is lubricated 

 and cleaned out at every discharge. One of these rifles was fired 

 eighteen hundred times in succession without cleaning or examina- 

 tion, under the inspection of some officers at Portsmouth, and was 

 then pronounced clean and in as good condition as when the experi- 

 ment commenced. It missed fire just twice in the eighteen hundred 

 discharges. Terry's breech-loading rifle was invented six or eight 

 years ago, and has now the enviable distinction of being exclusively 

 used by the British cavalry, hussars, dragoons, and mounted riflemen, 

 and the only breech-loader in use in the British army and navy ser- 

 vice. 



Patterson's Improved Gun Lock. Mr. Juan Patterson, an en- 

 gineer attached to the steel works of Messrs. Corning, Winslow & 

 Co., Troy, N. Y., is the inventor of a new method of firing a piece 

 of ordnance by means of a friction tube, or lock set in the cascabel, 

 or knob at the breech of the gun. The cascabel, instead of being per- 

 manently attached to the breech of the piece, is set into it by means 

 of a screw, and thus in reality the bore extends the entire distance 

 of the gun, so that when the cascabel is taken off one can look di- 

 rectly through the gun. By means of a spring, the cap is exploded 

 by the lock, and the gun discharged. The advantage of this means 

 of discharging an ordnance piece of this character by a lock set into 

 a detached cascabel, is, that in case it is necessary to retreat in an 

 action, and the gun cannot be brought off, the lock can be unscrewed 

 in an instant, and be carried away. The gun is thus disabled, and 

 cannot be turned upon the retreating body. Spiking a gun in such 

 an event is entirely unnecessary in Mr. Patterson's mode of firing it. 



New Mortar Cannon. The London Times thus describes a new 

 French invention : The tube or barrel is formed of several cylin- 

 ders or rings of cast or wrought iron. The interior of the tube is 

 rifled by means of a certain number of projecting spiral rods shaped 

 in triangular prisms. The tube can be lengthened at pleasure. -The 

 breech of the gun is a mortar, to which the tube is attached, and from 

 which it may be detached, either for the puropse of loading it at the 

 breech, or of making use of it as a mortar. It is alleged that this 

 cannon cannot become heated, and that the process of cleansing after 

 each discharge is unnecessary, except as regards the breech. Another 

 consequence said to follow from the non-heating of the barrel of the 

 gun is, that there is no danger of bursting, either from defect in the 

 metal or from over-charge. The gun may likewise be lengthened 

 or shortened at pleasure. The inventor states that a gun throwing 

 a shot of one hundred and twenty pounds' weight may be taken to 

 pieces and conveyed on the back of a horse or mule over roads im- 

 passable for carriages. He shows that there is a considerable saving 

 in the construction of this gun in consequence of the tube being of 

 open-work, and of iron, in place of bronze. It may be as light as is 

 consistent with the resistance which its weight must necessarily op- 

 pose to the recoil produced by its discharge. The inventor expects 

 that this gun will supersede mortars, and that every cannon mounted 



