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MINUTES OF PROCEEDINGS OF 
at extreme depression, touch the beams; it would, no doubt, add greatly to 
the strength of the ship's side if the ports could be reduced to half their 
present size, at the same time the port-sills would be higher out of the 
water, and the crew would be better sheltered, but to obtain these advantages 
we must have a greater height between the decks. 
The principal objections that have been urged against this principle of 
elevating, are, first, the slowness of the operation ; and, secondly, so reducing 
the size of the port that the captain of the gun has not sufficient field of 
view to distinguish clearly the object at which he is aiming. 
To the first of these objections, I attach little or no importance, as in 
actual warfare, sudden and rapid changes of elevation can never be required, 
and even if a sudden emergency did arise, it could be easily met, as in 
carriages constructed for muzzle-pivoting, the operations of elevating and 
loading can go on simultaneously, as I will explain hereafter. 
The second objection I freely admit; it being quite certain that better 
practice is to be made from guns mounted en barbette , than from guns in 
casemates, firing through embrasures only a few inches larger than their 
muzzles; but if we expect perfect protection for our gunners, guns, and 
carriages, we cannot expect an unlimited field of view; however, as I propose 
leaving a space of 6 in. over the gun, which will be constant, I think the 
field of view will be quite as good if not better than it is at present in our 
iron-clad ships, where, when firing with extreme elevation, it is absolutely 
nil [vide Diagram, Dig. 3). 
Dor all these reasons I came to the conclusion that our system of artillery 
would not be complete until muzzle-pivoting should be added to it. I 
consequently set earnestly to work to devise some practical method of 
pivoting guns at the muzzle, and in November, 1863, I laid before the 
Ordnance Select Committee a scheme for working a 68-pr. 95 cwt. gun on 
this principle on an ordinary casemate platform to give 1.0° elevation and 
5° depression. 
The Ordnance Select Committee approved of my proposal, and I was 
given a 68-pr. gun and ordered to make a carriage for it. 
I will endeavour now to explain my system of muzzle-pivoting; first, 
the principle upon which I obtain the motion; and, secondly, the application 
of that principle to practice. Before going further into this question, I must 
explain that any material support or pivot to the muzzle of the gun would 
be quite inadmissible; as in the first place, it would be putting the working 
pivot of the gun in its most vulnerable point, thereby rendering it liable to 
injury at any moment; and, secondly, it would interfere with the working 
of the gun, as it would, prevent its being run out in the embrasure or port. 
The pivot must be, so to say, imaginary, that is, the muzzle of the gun 
must be kept stationary, whilst the gun itself is being elevated or depressed* 
without any material support whatever. 
Drom the centre A [vide Diagram, Dig. 5) describe two concentric circles* 
and from A draw the straight line AB, cutting the circumferences of these 
circles at C and D, from the same centre describe the arcs BE and CE ; we 
will suppose these arcs to be attached to the line AB at G and A ). Now if 
the line AB be moved about A as a fixed point, the arcs BE, CE will always 
move in the direction of the circumferences of concentric circles due to theft 
