This instrument, the mekometer, together with the clinometer, for setting the gun for elevation independent of the sight arc, and an ordinary spirit-level to place on gun trail to tell which way the wheels or carriage of the gun are inclined on uneven ground (so altering the deflection scale), might in my opinion be supplied to every Naval field battery, heavy or light.[7]
I may mention that the 4.7's and 6" Q.-F. were often fired at elevations which did not even come on the graduated elevation arc, and so the clinometer had to be borrowed from the military and used to lay the guns; it is most useful.
For night firing on shore, as practised by us at Colenso and Spion Kop, guns are laid for required distant object just before dusk. The position of the wheels is accurately marked by pegs and lines, and when the gun is laid the sight is lowered to some white object placed fifty yards in front of gun, on which when dark a lantern may be placed; the elevation is read off either on arc of sight or by clinometer placed on the gun. To keep on firing at this distant object when dark, the gun is run out to same wheel marks every time and laid for same direction by the lantern on the near object, and elevation by clinometer. The C.O.'s of regiments always most kindly put their mekometer and trained observers at our disposal on escorting us up to a position.
A plane table survey, using a mekometer to measure one's base, is pretty easily made to get position of kopjes, trenches, well-defined gun emplacements and their ranges, roughly, but it wants a certain amount of time to do it.
As to the emplacing of a 12-pounder or other Q.-F. gun for attack or defence, all hard and fast rules may, in my opinion, be at once dismissed, the matter entirely depending on the nature of the ground occupied and the direction and extent of fire required. Still I submit the following points as being useful to remember:—
- (1.) Carefully select the ground. If on a ridge, hill, or kopje, the emplacement must be over the sky-line either on one slope or the other; take a place where Nature helps you, if possible screened by trees, free of rocks, and with soft ground, dongas, or water round it, so that the enemy's shells will bury themselves and not burst on striking. Of course in South Africa, except on the flat, this could hardly ever be done.
- (2.) The best form of emplacement is a gun pit about 1 foot 6 inches deep, according to our experience in Natal, the earth or rock taken out forming a circular parapet 3 feet 6 inches high, and as bulky or thick as ever you like on the front face, the floor of the pit being levelled and a gradual slope made out of it for guns to be moved easily in and out of the pit. The size of the pit should be just enough to allow the gun trail to move round on any arc of training when the gun muzzle is run out over the front face or parapet, and to allow three feet more over and above this for the recoil of the gun in the drag-shoes, so as not to fetch the trail up sharp on recoiling.
A narrow ditch may be dug all round the inside of the parapet to allow the crew to get into it for additional cover, and the ammunition boxes may either be placed in this ditch or a magazine dug and sandbagged over when plenty of time is available. A couple of drainage holes may be required in heavy rains to empty the pits on each side. The circular parapet can be built up any thickness, as just said; it should then be sandbagged over till the required height. If in grassy ground, instead of sandbags put large sods of grass to hide the emplacement and to keep the dust from flying, as sandbags are conspicuous. If neither grass nor sandbags are available, make your Kaffirs or camp followers cow-dung the surface of your parapet instead; this dries, and all dust under muzzle on firing is avoided. I constantly tried this plan and found it very effective.
Of all points this avoidance of dust is the most important, as, unless prevented, it rises in a cloud under the muzzle of the gun at every shot. At long ranges, used by the Boers and ourselves, it was almost impossible to locate a gun firing cordite or other smokeless powder except by this cloud dust. So avoid it at all costs. Make the colour of your emplacement as much like that of the surrounding ground as possible, including your sandbags, if used.
