Page:EB1911 - Volume 20.djvu/267

been secured, the adjustments to one sight made by the sight setter are simultaneously effected at the sight on the opposite of the gun.

From a drawing supplied by Messrs Vickers, Sons & Maxim.
Fig. 92.—Diagram of a 9·2-in. Gun and Mounting, “Hogue type.”
A,	Roller ring.	G,	Elevating press.	P2,	Breech operating hand-
B,	Recoil buffer.	H,	Shell-lifting press.		wheel.
C,	Gun cradle slide frame.	K,	Fixed armoured trunk.	R1,	Training rack.
D,	Loading tray.	L,	Radial shell-lifting crane.	R2,	Training engine.
E,	Shell carrier.	M,	Axial powder hoist.	T,	Turntable.
F,	Pressure water pivot pipes.	P1,	Breech block.	U,	Powder door.

In practice with the 6-in. and 4-in. guns, one man is responsible for the laying of the gun for direction, and has consequently only to think about the coincidence of the vertical cross-wire with the target, while another man, who also fires, keeps the gun laid for elevation, and is responsible only for the coincidence of the target with the horizontal cross-wire. The 12-pounder has one sight only, one man being considered sufficient to keep the gun laid for elevation as well as for direction, and to fire. It is essential that the sights shall be unaffected by the recoil of the gun, so that they can be adjusted up to the moment of firing by the sight-setter, and that it shall not be necessary for the gunlayer to remove his eye from the telescope while the gun is being fired and reloaded. It is also essential that the sights shall move automatically in elevation and direction with the gun. These two requirements are easily met in the hand-worked mountings by the attachment of the sights to the cradle, which does not move on recoil, and remains constantly parallel to the gun; but in turret mountings the case is more complicated and involves greater complexity of gearing.

The older turret sighting arrangement consisted of two horizontal shafts, one for each gun, running across the turret, which were rotated by pinions gearing into racks underneath the gun-slides, the latter remaining of course always parallel to the guns. Pinions keyed to these shafts geared in their turn into racks formed on vertical sighting columns in the sighting positions, these columns, which carried the sighting telescopes, accordingly moving up and down with the guns. With this arrangement an appreciable amount of backlash was found to be inevitable, owing to the play between the teeth of the several racks and pinions, and to the torsion of the shafts, and the arrangement was also open to the objection that the telescopes were much exposed to possible injury from an enemy’s fire. These defects have been very largely obviated by the “rocking motion sights,” which have been fitted in the turrets of the latest British battleships and cruisers. In these sights a sight-bracket is secured to and rotates with the trunnion of the mounting; the sight-carrier and telescope move along the top of the sight-bracket, on a curved arc of which the trunnion is not the centre. When the sight js at zero, the telescope is parallel to the axis of the gun, while to adjust the sight, the sight-carrier with telescope is moved along the curved arc by means of a rack and pinion a distance corresponding to the graduations shown on the range dial, which is concentric with the pinion.

Organization.—The organization of a large ship for action is necessarily highly elaborate. Among the officers, next to the captain, the most important duties are probably those of the fire control officer. He is in communication by telephone or voice tube with each of the several units composing the ship’s armament. This office is usually filled by the gunnery lieutenant. In the conning tower with the captain is the navigating officer, who attends to the course and speed of the ship, assisted by petty officers to work the wheel and engine-room telegraphs. The torpedo lieutenant, or another officer at the torpedo director, is also in the conning tower, prepared to fire the torpedoes if opportunity offers. Other officers of the military branch, and marine officers, are in charge of various sections of the “quarters.”

The rate of advance in naval gunnery has been much accelerated since 1902. The construction of the “Dreadnought,” which embodied a new principle both in nature and disposition of armament, the rise of the United States and Japanese navies to the first rank, and the practical experience of the Russo-Japanese war, were all factors which contributed to the increase of the normal rate of advance due to progress in metallurgy and engineering science. In the British as well as in other navies, notably those of Germany, the United States and Japan, ever-increased attention is being devoted to the attainment of a rapid and accurate shell-fire, and large sums are being expended upon fire control instruments and elaborate aiming and sighting appliances. Size of armaments, power of guns, resistance of armour, efficiency of projectiles, and, above all, rapidity and accuracy of fire, all seem to be advancing with giant strides. But there are two important ingredients of naval gunnery which are not subject to change: the human factor, and the factor of the elements—wind, sea and weather. The latter ensures at any rate one datum point to the student of the science, that is, that the extreme range in action is limited by the maximum distance at which the enemy can be clearly seen, which may be considered to be a distance of 8000 to 10,000 yds. The permanence of the human factor assures that, however great the advance in material, and, provided that no great discrepancies exist in this respect between opposing navies, success at sea will be the lot of the nation whose officers are the coolest and most intelligent, whose men are the best disciplined and best trained, and whose navy is in all respects the most imbued mth the habits and traditions of the sea.  (S. Fr.)