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TRANSACTIONS OF SECTION G. 943 
and which gives the best protection for the breech mechanism, for the hoist and 
rammers. The operations of unlocking the breech-block, withdrawing it, traversing 
it, inserting a loading tray, and, after completing the loading, performing the same 
operations in reverse order, are all done by hydraulic power, and the fittings are so 
devised that unless the gun is properly locked and run out it cannot be fired, 
In certain foreign vessels provided with the hydraulic breech mechanism, a valve 
has been arranged which makes in their proper order, and in that order only, the 
eight or ten movements necessary to open and close the breech of the gun; but this 
system has not been adopted in our own navy. 
The sights are carried on the top of the turntable, or, in the case of a turret, on 
the turret roof, and are worked automatically by an arc attached to the gun slide, 
gearing into cog-wheels, with shafting reaching to each sighting position. 
The system of recoil press adopted on all these ships is that which lends itself 
most readily to employment also as a running-in-and-out press. It consists of a 
simple cylinder carried in the middle of the slide, having working in it a ram with 
piston, attached at the front end to the carriage. Spring-loaded valves are placed 
in the recoil ram piston and at the end of the cylinder, and by these the water 
escapes when the gun recoils. The water which passes through the cylinder 
valves runs to the exhaust-pipe, while that which passes through the piston valve 
yemains in the front of the cylinder, and prevents the gun charging out again. 
When the recoil press is used to run the gun in and out these valves are 
inoperative, as they are loaded much above the working pressure in the hydraulic 
mains. The hich pressure of recoil does not enter the hydraulic mains, as the 
supply to the rear of the press, where alone the high pressure of recoil exists, is 
made backwards and forwards, through a valve which shuts itself automatically 
when not in use. 
Before leaving the working by power of heavy guns, there is one example of 
mounting a pair of guns en barbette which, although it has many points in 
common with the system I have just described, has also some points of difference, 
which it may be worth while to note. 
Objections have sometimes been urged to the fixed loading station on the 
ground that it is necessary to bring the guns to it and lock them there until 
sponged and loaded, thereby involving, not only a loss of time, but under certain 
conditions exposing them more to the enemy’s fire. 
In ships of the Re Umberto type, what is termed an all-round loading is 
obtained by bringing up the ammunition through a central hoist to the deck below 
the turntable. From this central hoist it is transferred to two other hoists, which 
are carried on the turntable behind the guns. The transfer is made by hand for 
the powder and by sliding down a tray for the projectile, this work being 
rformed by men on the deck below the turntable. The hydraulic rammers are 
fixed to the turntable, and are very much shortened by being made with more 
rams. In spite of this arrangement, however, the hoists are rather cramped, and 
the breech mechanism has to be made to pass from behind the gun, so as to 
permit the gun to recoil, and the gun is rather further forward than usual when 
run out. 
With these reservations, however, the system has advantages: the reduction in 
the armour required to protect the turntable and its machinery is considerable, and 
the redoubt being round instead of pear-shaped presents a smaller and stronger 
surface to the enemy when broadside on. 
I very much doubt, however, whether with this system there can be any 
advantage in rapidity of tire. Training to the loading station is in our navy very 
quickly done, and the turntable is rotated while the guns are being run in or out. 
It is hardly necessary to say that hydraulic machinery for guns was worked 
out by my friend and late partner Mr. George Rendel, and up to the end of ;1881 
all details connected therewith were made under his management. 
I ought perhaps to give you some idea of the rate at which these heavy guns 
_ worked by power can be fired. 
+ In the case of the Benbow, with the 110-ton gun the time from ‘load’ to 
‘ready’ was 24} minutes. In the firing trials of the Zrafalgar four rounds were 
