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MINUTES OF PROCEEDINGS OF 
the breech.* The breech-carriage also recoils, and this, together with 
some play between the breech and the bottom of the guide bars, pre¬ 
vents any alteration of elevation during the instant of firing. 
The weight of the breech is kept as small as possible, and this no 
doubt will have the effect of reducing the amount of pressure of gas on 
the shot ; but it will only be to a very slight extent. I have taken the 
breech as fifty-six times the weight of the shot; so that the pressure 
would be about 1 per cent, less than in ordinary guns, which are about 
112 times the weight of the shot. The initial velocity of recoil will 
thus be twice that of an ordinary gun, and this would require four 
times the amount of resistance to pull it up in the same space. Twice 
the resistance, however, would pull it up in double the space; and 
I propose doing it in this manner, so as to give sufficient room for 
loading. There are two sets of compressor bars which act on the 
breech, one on each side immediately inside the guide bars. There 
would, besides, be compression between the breech carriage and slide, 
so as to pull up the carriage when it had recoiled to a suitable distance. 
The construction of the carriage would also bring the action of gravity 
to bear at the most suitable moment to produce the same effect. 
Breech ropes are added for greater security. It may be supposed that 
this double strain would be apt to injure the pivots with a very heavy 
gun; but it will be seen that this is not likely to happen, when it is 
considered that what injures the pivots is not the compressors, but the 
friction which is brought to play between the carriage and slide during 
the impact of discharge. In an ordinary gun, the whole weight of the 
gun rests on the carriage, but in the case of this gun it does not; so 
that the carriage can more readily slip away. 
When the breech-piece is back, the gun is loaded at the breech. 
The compressors are then released, but not before the breech has been 
secured to its carriage, in the position it may then occupy, by chains, or 
some other contrivance. This prevents the breech from descending, 
and is useful, because the higher the breech, the more readily will it run 
forward. For if the guide bars are above the horizontal, they tend to 
help the breech forward; but if below, they tend to retard it in running 
forward. Should the breech accidentally get low on its carriage, it 
would have to be run up the bars by means of the running-out-and-in 
gear. Wheels would be brought into play between the breech and 
guide bars, and between the breech carriage and slide; but they are not 
shown in the model, as their action is well known in the Working of 
heavy guns. 
This breech action is very simple, and suited to very heavy guns, 
where great weights must necessarily be moved. The explosion opens 
the breech, and alters the position of the gun from that shewn in 
Fig. 16 to that shown in Fig. 17. Gravity brings it back again to its 
original position. 
A much smaller breech carriage can be used, which provides for only 
# Or the wad might remain in the bore after the pressure had ceased, to prevent any escape of 
smoke, and could be withdrawn at leisure. 
