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flat-beaded. Sir. Whitworth/ s theory is, that the flat-headed 
shot punches out a portion of metal clean, while a great deal of 
the momentum of the pointed shot is lost in compressing- the 
metal sideways, like a wedge, as it penetrates ; thereby at each 
instant creating a greater opposition to its advance. These 
shot are made of steel or homogeneous iron, or faced with it. 
At the late experiments at Shoeburyness, the Whitworth 
120-pounder, at a range of 800 yards, sent a flat-headed shell, 
which, with its bursting charge of 5 lb., weighed 150 lb., 
through a target consisting of 5 -inch iron plates, on a 12 -inch 
teak backing, with a f-inch wrouglit-iron skin within, the shell 
bursting inside. The 70-pounder, at a range of 600 yards, 
sent a shell weighing, with its bursting charge of 3 lb. 12 oz. 
of powder, 81 lb., through If-inch plates, with 18-inch teak 
backing and a -f-inch skin. No fuze is required for these 
shells, as the passage through the iron plates heats them suffi- 
ciently to ignite the powder. In the ordinary Whitworth shell 
the percussion arrangement is not required in the fuze, as the 
flame can communicate with it. In the Whitworth breech- 
loader, the breech is closed by a cap which screws on outside. 
This cap works in an iron hoop, which is attached by a hinge 
to the side of the breech. When unscrewed, the cap is by this 
means opened back like a door, disclosing the bore for the 
insertion of the shot and cartridge. The vent is in the centre 
of the cap, in the axis of the gun. The cartridge is contained 
in a tin or copper case, Avhich prevents any escape of g-as. The 
mouth of the cartridge is closed by a lubricating wad, which 
lubricates and cleans the bore after each discharge. This wad 
has also now been adopted with the Armstrong gun, and avoids 
the necessity of constant sponging out. 
These few remarks would scarcely be complete without some 
comparison between the rival systems. General Morin, in the 
June number of the Annales da Conservatoire Imperial des 
Arts et Metiers, makes some remarks which appear to be just, 
though there are some portions of the article in which the able 
author seems to have been labouring under a misconception. 
He says that the advantages of the Armstrong projectile are 
compensated for by numerous defects. The manufacture of the 
projectiles is very delicate. Them nature is such as to require 
a care in preservation which the hazards of war render it im- 
possible to afford them. While, on the other hand, after 
describing the Whitworth system, and commenting on what he 
considers an excess of nicety and exactness in their manu- 
facture, as shown, which is not by any means indispensable, but 
may on service be found not only superfluous but inconvenient, 
— he speaks highly of the Whitworth principle, and says that, 
when the niceties are modified so far as experience and the 
