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Gunnery Results: The 12-pounder Q.-F. Naval gun—Its mounting, sighting, and methods of firing—The Creusot 3" gun and its improvements—Shrapnel fire and the poor results obtained by the Boers—Use of the Clinometer and Mekometer—How to emplace a Q.-F. gun, etc., etc.
A word or two now as to what we with the guns have learnt during the campaign, although I feel that this may be rather a dull, professional sort of chapter except to those interested in guns and gunnery, and that the subject as treated by myself may be open to criticism from others similarly engaged. I may certainly say that it was not for at least three months after our opening fire at the first battle of Colenso (December 15th, 1899) that I personally felt myself as "fairly well up" to the constantly varying conditions of gun positions, gun platforms, enemy's positions, and the ever-changing "light and shade" of the South African climate, against all of which one had to fight to get correct shooting; the last-named of these, viz., "light and shade," being perhaps our greatest bugbear, often throwing one many thousand yards out in judging a range by eye, which gift is, I think, the best a gunner can possess!
Then, too, the Naval guns as they were sent up (owing to the work being pushed at the last moment), some on high wheels and some on low ones, some with drag-shoes (p. 102) opened out and others which wouldn't take the wheels, some with the wires from them to trail plate handles the right length and others much too long, caused (I am talking of the 12-pounders) these guns, instead of forming a level shooting battery, to be each one a study in itself as regarded its shooting powers; and we constantly found one gun shooting, say, three or four hundred yards harder or further than the one next to it although laid to the same range on the sights. This at first sight was rather mystifying, but all these small but important matters above mentioned were not long in being put to rights. On any future occasion such defects will, of course, be avoided from the start by the guns being altogether more strongly mounted on broad-tyred wheels and broad axles of similar height, size and pattern, and, above all, with a strong and uniform system for checking the recoil of the carriage, of which the drag-shoe, as it was fitted and sent up to us, was certainly not capable.
I am rather keen on this question of the best means of checking the recoil of a field carriage. A very strongly made drag-shoe fitted with chains to the centre of gun trail will do very well; and these were, later on in the campaign, fitted by the Ordnance authorities at Maritzburg to new "Percy Scott" carriages, which they sent up to us to replace the original "Percy Scott" carriages, which, as I remarked before, were not strongly enough built, particularly as regards the wheels, to stand any very bad country or a lengthened campaign, in both of which we found ourselves involved. In these remarks, please let no one think that I am running down the 12-pounder carriage for a purpose; not so. I simply wish to point out details that, if more time had been available, would certainly have been avoided in them by their very clever designer, Captain Percy Scott, R.N., to whom the (p. 103) service in general (and I personally) owe a debt of gratitude; for assuredly not a Q.-F. gun, or a single one of us with the batteries, would ever have been landed unless it had been for him and his brains and his determination to have the Royal Navy represented in the campaign, as was their due—being on the spot with what was most wanted, namely, heavy guns.
Here I wish to distinctly state my own opinion, and that also of the many officials and gunners, Naval and Military, with whom I have talked over the matter, i.e., that not only did the Naval guns save Ladysmith, but they also in a great measure helped to save the campaign outside for its relief, and with it Natal. And my opinion now, when the war is nearly over, is only strengthened and confirmed by what I have heard the Boers say of the guns, viz., that they are the only things when using shrapnel that have shaken them much during the fighting, and, considering the country, naturally so. That it was to the Navy and not to the garrison gunners that the original credit has gone, was simply because we were here and they were at home at the start. One is, as regards their gunnery powers, as good as the other, and the garrison gunners earned their laurels later on. Still, I have a great hankering after a gun's crew of "handy men" to beat any crew in this world for all-round service and quick shooting, and I am ready to back my opinion heavily.
Returning from this digression to the subject of recoil, we found that sandbags placed at a certain distance in rear of each wheel not only effectually checked the carriage, but also (a great consideration) ran it out again. This system was used both by the 4.7's and ourselves at the end of the war; and seeing that the guns had only half crews, it was a most important saving to men who had perhaps marched ten miles, loaded and off-loaded ammunition, (p. 104) and then had perhaps to fight the guns under a hot sun for hours. To fill and carry the bags, however, is a nuisance, and some better system on the same principle is needed, such as the inclined wedges that I saw by photos the Boers were using in rear of wheels; and I should very much like to see some such system substituted for our present one. I have not seen the hydraulic spade used, perhaps that is the best.
To put it briefly, the hastily improvised gun-carriage of the 12-pounders had, on account of this very haste, the following defects:—
(1.) Too weak generally in all parts, particularly wheels and axles, for any long campaign.
(2.) Wheels and axles being a scratch lot, none in any of the batteries were interchangeable, which caused many times later in the campaign when wheels began to give out, much anxiety. Several times we only had guns ready for action or trekking by the "skin of one's teeth," and it must be borne in mind that any new wheels wired-for sometimes took two months to arrive on the very overcrowded railway—a single line.
(3.) The system of checking the recoil of the field carriage was a bad one.
(4.) All the 12-pounders except two were in the first instance sent up without limbers, and therefore had to be limbered up to wagons. This for practical purposes in the country we had to trek over was absolutely useless and caused endless delays. Eventually we all got limbers built at Maritzburg, and equivalent gun-oxen to drag the guns separately from the wagons.
(p. 105) (5.) The trail of the gun consisted of a solid block of wood some 12 feet long; so that if one laid the gun to any long range (in most over 7,000 yards, I think) the oil cylinder under the gun, on trying to elevate it, would bring-up against this trail and prevent laying. This therefore necessitated digging pits for trails to shoot much over 7,000 yards, which in bad ground often took some considerable time. To obviate this defect would of course be very easy with a steel trail of two side plates, and space for gun and the cylinder between the sides.
(6.) The general idea of all the mountings I saw was narrow axles and high wheels, whereas, for all trekking purposes, it should be broad space between the wheels and low wheels. This was amply proved to us by the number of times the high-wheeled narrow mountings upset on rocky ground, whilst the broad low type went along steadily. The 12-pounder gun itself did its work beautifully, shooting hard and lasting well, and owing to the dry climate of Africa we had no trouble at all to keep the guns clean and all gear in good order.
(7.) Perhaps the most troublesome defect of all was that the gun-carriage had no brake fitted. The gunnery drill-book system of "lash gun wheels" may be at once erased from the book for all practical purposes over any rocky or bad country; it simply, as we soon found, tears the wheels to pieces, and chokes the whole mounting up. An ordinary military Scotch cart brake, or a brake fitted as the trek wagons (p. 106) here have, under the muzzle of the gun on the forepart of the wheels, acts very well, and my bluejackets, although not carpenters, fitted these for me. They are screw-up brakes.
The sighting of the gun (drum and bar system) cannot be beaten, I think. Perhaps a V-shaped notch to give one the centre of the H, or hind sight, might be an improvement, as here personal error often occurs. Lieutenant, now Commander, Ogilvy, R.N., always made his men correct their final sighting of the gun for elevation from about six paces in rear of the trail, and my experience is that this is a small but important matter, especially for fine shooting say at a trench at 5,000 yards, which merely appears to one as a line on the ground. One invariably finds that the gun, with the eye of a man laying close up to the hind sight, is laid slightly short of the object; so this should be noticed in the gunnery drill-book as regards field guns. Telescopic sights, the patent, I believe, of Lieutenant-Colonel L. K. Scott, R.E., were sent out and used by us with the 12-pounders to fire on the trenches at Spion Kop and Brakfontein, when fine shooting was required. These sights had the cross wires much too thick, so we substituted cobwebs picked off the bushes and stuck on with torpedo composition, and these did admirably. Still this sight was not altogether a success. The power of the telescope, especially in the rays of the sun, was poor, and it took a man a long time to lay his gun with it, thus further reducing the quick-firing power of the 12-pounder reduced already by the recoiling field carriage. As to the 4.7's, it was found that the ordinary Naval small telescope, fitted on a bar and with light cross wires, could not be beaten as a sight for ranges they had to fire at. It is a very good useful glass, and it (p. 107) was, I believe, used both in Natal and elsewhere right through the campaign, and I unhesitatingly give it the palm.
As to the system of firing and gear used, electric firing was very successful as long as one had the gear for refitting and repairing and an armourer attached to one's guns; this, of course, as the guns became split up into pairs was impossible, and I may say that carting electric batteries (which of necessity for quickness have to be kept charged) in wagons or limbers over rocks and bad roads, and with continual loading and off-loading, becomes a trouble and anxiety to one. So for active service I should certainly recommend that percussion firing should be regarded as the first and principal method to be used with guns on the move, carrying also the electric gear for use if guns are left for any time at fixed spots as guns of position. I may here remark that when firing with electricity from a field carriage the battery has to be placed on the ground, clear of recoil, and therefore the wire leads must be adjusted in length accordingly. I am uncertain whether our other 12-pounders used mostly electric or percussion, but I think on the whole, percussion; and, speaking for myself, I certainly did so after experiencing the disappointments which miss-fires often gave one, when trying to get in a quick shot, say from the line of march, with the electric gear. These "miss-fires" are, moreover, often unavoidable under active service conditions, such as we had with our semi-mobile guns. The guns and connections get sometimes an inch thick in mud or dust and require time to clean, when one has no time to spare: the use of percussion tubes avoids all this.
Before we leave the subject of guns the following description of the French 3" Creusot gun by the Revue d'Artillerie will be of interest, viz.:—
(p. 108) South Africa.—The Field Artillery of the Boers consists for the most part of Creusot 3" rapid-firing guns made after the 1895 model. These guns were purchased by the South African Republic during the year 1896.... The gun, which is constructed of forged and tempered steel, has a 3" bore. Its total length is 8 feet and its weight is 726 pounds. The body of the gun consists of three elements:—1. A tube in which the breech piece is fixed. 2. A sleeve covering the tube for a length of 3 feet 6 inches. 3. A chase hoop. The chamber is provided with twenty-four grooves of variable pitch which have a final inclination of 8°.
The system of breech closing is that of the interrupted screw, which presents four sectors, two of them threaded and two plain, so that the breech is opened or closed by a quarter revolution of the screw. The mechanism is of the Schneider system, patented in 1895, and has the advantage of allowing the opening or closing of the breech to be effected by the simple motion of a lever from right to left, or vice versâ.
The gun is fired by means of an automatically-cocked percussion apparatus. A safety device prevents any shots from being fired until after the breech is closed.
The carriage is provided with a hydraulic recoil-cylinder fitted with a spring return. It is also furnished with a "spade," which is placed under the stock at an equal distance from the trail and the axle, and which is of the model that General Engelhardt has adopted for the Russian Artillery.
During a march this spade is turned back and fastened to the stock. The carriage is likewise provided with a road brake, which is to be employed in firing only when the nature of the ground is such that the spade cannot be used.
The gun is placed in a bronze sleeve that carries the brake cylinders and the various other connecting pieces for the return spring and the aiming apparatus.
The hydraulic recoil consists of two cylinders placed laterally and at the height of the axis of the piece.
The axle has the peculiarity that in its centre there is a wide opening in which are placed the cradle and the gun. It is provided with two screw trunnions, around which the pivoting necessary for lateral aiming is effected. This arrangement of the (p. 109) gun with respect to the axle has the effect of greatly diminishing the shocks that firing tends to produce.
Elevation and depression are accomplished by rotating the axle in the wheels of the carriage. This is done by means of a crank which, through an endless screw and pinion, controls a toothed sector attached to the sleeve.
Pointing in direction is done by means of a lever known as a tail piece. Mounted upon the axle there are two small sights, forming a line of aim, that permit of bringing the carriage back in the direction of the target as soon as a shot has been fired. All that the gunner has to do is to give the piece a slight displacement laterally with respect to the carriage by means of a hand-wheel, which turns the gun 2° to one side or the other.
The line of aim is found by a back and front sight arranged upon the right side of the sleeve in which the gun is mounted. The back side permits of aiming while the gun is being loaded. It carries a small oscillating level that indicates the elevation of the gun during rapid firing.
The weight of the carriage, without wheels, is 1,146 lbs. and with wheels, 1,477 lbs.
The ammunition consists of cartridges containing charge and projectile and having a total weight of 19 lbs. The powder employed is of the smokeless kind, designated by the letters B.N. The weight of the charge is 1-¾ lbs. The projectiles are of three kinds—ordinary shells, shrapnel shells, and case shot. The weight of each is the same, say 14-¼ lbs. The shrapnel shells contain 234 balls, weighing 155.8 grains each, and an explosive charge of 3.13 ozs.
As the gun can be pointed at a maximum angle of 20°, and the initial velocity is 1,837 feet, the projectiles can be fired to a distance of 26,248 feet.
The crew necessary to serve the gun consists of six men—a gunner, a man to manœuvre the breech-piece, a man to manœuvre the pointing lever, two men to pass the ammunition, and a man to regulate the fuse. The rapidity of firing can easily be raised to ten shots a minute.
The accuracy of the gun is most remarkable. Upon the occasion of the trials made when the guns were received, the following firing was done: a regulating shot, a first volley of six (p. 110) shots in forty-two seconds, and a second volley of six shots in forty-six seconds.
The fore carriage of the gun and that of the caisson are identical. They carry a chest containing thirty-six cartridges, and are capable of accommodating four men.
The back carriage of the caisson carries two chests like that of the fore carriage.
The total weight of the gun and fore carriage loaded is 3,790 lbs., and that of the caisson 4,330 lbs.
On reading over this description of the French 3" Creusot gun, it seems to me that the kind of axle used with it is first class and should be used in our field carriages for quick-firing guns; it must certainly take the strain of recoil off the centre of the axle, which recoil we found cracked our axles as we used them (once in my own guns) so badly that the whole thing had to be shifted and replaced. Another advantage it has is to lower the whole gun and mounting, and the centre of gravity of the weight of it and carriage, and therefore the gun is much harder to upset on rocky ground or going up steep precipices, as we had to do in Natal. This detail of wheels and axle is, I think, the most important one almost in a field carriage. The axle I mention is one bent down in its centre for about two-thirds of its length.
In regard to the ammunition. The cordite charges in their brass cylinders and zinc-lined boxes did admirably, and the amount of knocking about which the cases and boxes out here stand is marvellous. At one time early in the campaign before Colenso and Ladysmith, a decided variation in shooting of our guns was noticed, and was put down in many cases to the variation of the cordite itself, the brass cases sometimes lying out, in fact, in a powerful sun for hours, while the guns were waiting or in action, and often becoming then too hot to touch. (p. 111) Now, however, I personally don't think that this theory was right but am of opinion that the variation then noticed, and even after in the shooting, was simply due to the varying recoil of guns on different slopes of ground and with indifferent drag-shoes. Royal Artillery officers confirm one in this opinion.
As for the shells, both common and shrapnel, they stood the knocking about well, and I never saw or heard of a single common shell used with 12-pounders not exploding on striking, which speaks well for the base fuse. The shrapnel I am not quite so sure about; one noticed often a great deal of damp collected in the threads of the fuse plug and nose of the shell; owing, I presume, to condensation in their shell boxes under the change of heat and cold. Still they did very well and I think seldom failed to burst when set the right distance. I say the right distance because this at first was a slight puzzle to us, the subject of height in feet above the sea-level of course never having before presented itself to us as altering very considerably the setting of the time fuse; and I don't think that a table of correction for this exists in the Naval Service; at any rate, I have never seen one.
To illustrate this, we found at Spion Kop (about 3,500 feet above the sea-level) that it was necessary to set the time fuse for any given range some 500 yards short to get the shell to burst at all before striking; and on the top of Van Wyk, fronting Botha's Pass (some 6,500 feet above sea-level) I had to allow the fuse 800 to 900 yards short of the range, and similarly at Almond's Nek. This is, I take it, due to the projectile travelling further against a reduced air pressure at any height than it does for the same sighting of the gun at sea-level, for which of course all guns are sighted. I should like to talk to experts (p. 112) regarding this as we are not quite sure about it up here.
Of course this firing from a height gives one therefore some 1,000 yards longer range with shrapnel, say at 6,000 feet up, which is a most important fact to remember in shore fighting, and was well illustrated by the Boer 6" gun at Pougwana Mount (7,000 feet) over Laing's Nek, killing several of our Infantry on Inkwelo (Mount Prospect) at 10,000 yards range; of course this was helped by the height they were up, as well as by their superior double-ringed time fuse which we have picked up on their shrapnel, and which gives them in shrapnel fire a great advantage over any of our guns, which have not got these fuses at present. It is interesting to note that many 4.7 lyddite shells were picked up, or rather dug up, by our own men and others, quite intact—this, of course, was always in soft ground, noticeably near the river (Tugela), and shows that the "direct action fuse" should have been screwed into the nose of the shell, instead of the "delay action fuse" that it had in it for use against thin plates of ships.
Before leaving this subject of the gun and its fittings (12-pounder), I again wish to emphasise the fact of how important is the question of recoil. At one time, in front of Brakfontein with the 8-gun 12-pounder battery, we all dug trail pits and blocked the trails completely up in rear to prevent the guns recoiling at all on the carriage. This most certainly gave a gun thus blocked up over one allowed to recoil on the level an advantage of several (p. 113) hundred yards at an ordinary range of say 6,000 yards; but of course it threw on our weak makeshift wooden trails an undue strain, and after a couple had been smashed had to be given up. Still, although I would never advocate doing this to any field gun (i.e., bringing a gun up short as it shakes the mounting too much) the fact remains that the range or shooting power of the gun may be varied with the recoil in a great degree, and that therefore what I mention about a system to check recoil uniformly and with certainty seems to me to be an important one with our Naval field guns. This fact of increased range, got by blocking up a gun, is useful to remember in many cases, especially in this war when the Boers had the pull of our guns at first, and when it might have been worth while just temporarily disabling one gun, and to get one shot into them and so frighten them off.
The newspaper controversy, very hot at one time, as to whether the Boer guns were better or not than ours, and the ridiculous statements one both read and heard from persons who knew little about the matter, were rather amusing and perhaps a little annoying. I unhesitatingly state that on all occasions the British Naval guns inch for inch outranged and outshot the Boer guns; and that the 4.7 Q.-F. even outranged, by some 2,000 yards, the Boer 6" Creusot. This I saw amply proved, at least to my own satisfaction, at Vaal Krantz, when the Boer 6" gun on about the same level as our 4.7 was, on Signal Hill, vainly tried to reach it and couldn't, whilst our gun was all the time giving them an awful hammering and blew up their magazine.
In one way, and one only, the Boer guns had the advantage over us in shooting, that is, with their shrapnel shell, many of which were fitted with a special long range time fuse (double-ringed); here they certainly overshot us, but (p. 114) failed to make much use of the advantage, as they invariably burst their shrapnel, through incorrect setting of fuse, either too high up in the air to hurt much or else on striking the ground. Another great advantage the Boer guns as a rule possessed was the heights at which they were placed, generally firing down upon our guns and troops. Notwithstanding all this, I say again, that their guns inch for inch were not in the hunt with ours as regards shooting power, nor was this likely or possible seeing the great length of the Naval Q.-F. gun and its much heavier charge.
It must be remembered that Naval guns are solely designed and built for use at sea, or in forts, or against armour; and so to get the necessary muzzle energy, velocity, and penetration, a long gun is required; whereas the Boer gun was essentially a field or heavy land service gun. Their guns up to the 6" being on proper field mountings, and much lighter, shorter in the barrel, and consequently more mobile than ours, while firing a lighter charge; and perhaps in this way only it could be said that they were certainly better and handier than our guns. On the march and trekking up mountains this must have helped them a good deal, and from photos which I saw after the Boers had been driven out of Natal I should certainly say that their heavy guns on the march must have been much easier to move than ours.
To give an idea of the difference in weight between the heavier guns I may quote the following figures; that of the Boer guns I take as I read of them in Military Intelligence books:
British Naval 6" Q.-F. gun (wire)
7 tons 8 cwt.
Boer 6" Creusot gun, 2 tons 10 cwt.
British Naval 4.7 Q.-F. wire gun
2 tons 2 cwt.
(p. 115) From these weights it may be at once noticed that inch for inch there is no comparison between the Boer and British heavy gun as regards range and power of gun itself, consequent on our heavier charges. Taking their 3-½" Creusot Q.-F. guns (15 lbs.) and comparing them with our Elswick Naval 12-pounders I should say that there is little to choose between them, they having the advantage only in their long range fuses for shrapnel shell, which fuses should be issued to ours as soon as possible. One always heard these small French Q.-F. guns alluded to with great awe as the "high velocity" gun of the enemy, but I doubt much if they have one foot per second more mean velocity at ordinary ranges than our Naval 12-pounder, although perhaps they may have more at the muzzle, which is of little account.
To illustrate what small use the Boer gunner made of his advantage over us in long range shrapnel, I should say that it was generally noticed by all in the Natal Field Force how very high up they burst their shell as a rule, and so doing much less damage than they might have done; as Tommy described it, the bullets often came down like a gentle shower of rain and could be caught in the hand and pocketed. This of course, I should say, was the result of faulty setting of their time fuse; probably they did not apply the necessary correction for height above sea-level and so the shell either burst at too high a period of its flight, or else on striking did little damage to us. The front face of this kopje from where I am now writing (Grass Kop at Sandspruit, and 6,000 feet high) is full of holes made by Boer shrapnel shell, burst after striking in the hole dug by the shell itself and leaving all their bullets and pieces buried in these holes. There was no damage done by their heavy shrapnel fire at all when the Dorsets took the hill, and solely because of this (p. 116) faulty setting of the time fuse. We have dug up many of these shells here, and bullets simply strew the ground.
The 12-pounder gun limber, especially made by our Ordnance people from a design supplied by Lieutenant James, R.N., when at Maritzburg in November, was afterwards supplied to all the guns, and none too soon; but we did not get them till Ladysmith was relieved and they were badly wanted all the time. These limbers were very well made and very excellent, fitted to carry forty rounds complete of 12-pounder Q.-F. ammunition which was invariably found by us as sufficient, as a first or ready supply, giving eighty rounds to a pair of guns. More could, however, have been carried if necessary, up to sixty rounds complete on each limber; these limbers were strong, with very good wheels and broad tyres (a great contrast to the wretched little gun wheels we had to get along with at one time) and on them there was room also for gun's crew's great-coats, leather gear, gun telescopes, and other impedimenta, which was most convenient.
One fault in them, I think, might be corrected if again required; i.e., the platform or floor of the limber instead of being built only on the forepart of the axle should extend also behind or on rear side of the axle; by this means the Q.-F. boxes of ammunition may be distributed to balance the weight equally on each side of the axle, and so bring the least weight possible on the necks of the oxen or other draught animals drawing the limber and gun along. This, in a hilly country, is important.
I would here note that when on the march with guns under any conditions, one's men should always be allowed to march light, slinging their rifles on the gun muzzles and putting leather gear with S.A. ammunition, water bottles and days' provisions handy on top of the limbers. (p. 117) The carrying of any of these things only exhausts the men for no object, and when one remembers what heavy work they may have to do on the march at any moment—bringing guns into action, rapid firing and running out the guns, digging pits and trenches, off-loading and loading the Q.-F. ammunition, and keeping up a supply which in South Africa at any rate may be at the bottom of a steep kopje with the gun at the top—one recognises the great advantage gained in giving the men as much latitude as possible, and bringing them into action after a march comparatively fresh. For these reasons I would advocate that a gun limber should be made for any service gun, with the object of allowing a certain amount of extra room for the gun's crew's gear and stores.
In respect to range finding, the mekometer (range finder) as supplied to the Royal Horse Artillery and Royal Artillery and also to every company in a regiment (and which therefore was easy to borrow during the campaign), proved most useful to us in getting ranges roughly. To get a range over 5,000 yards one has to use the double base with this instrument, and ranges may then be found up to 10,000 yards, and, with practised observers, fairly correctly. At any rate it is most useful to have something to start on when you get up into position. This instrument is extremely small and portable and should be supplied to Naval field batteries, and also a certain proportion to the rifle companies for land service; it may be carried slung like a small Kodak camera on one's back. Of course ranges can be very quickly found by shooting one or two shots to find them out, and this was done by our guns a good deal, and necessarily so when in action when one has no time to waste and the objects are moving ones; but I strongly advise anyone who gets his guns into a position where he is likely to stop, such as in defence of a camp, (p. 118) or on top of a kopje defending a railway line, or in position to bombard an enemy's fixed trenches and lines, at once to find his ranges roughly all round to prominent objects by the mekometer, as it gives one added confidence and is invaluable when shooting over the heads of one's own men to cover their attack, which is often a ticklish job and to be successful must be continued up to the very last moment it can be, with safety.
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.
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 (p. 119) 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 (p. 120) 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.
Footnote 6: I am since glad to hear from Lieutenant Henderson of H.M.S. Excellent, that he is engaged in working out a table of corrections, such as I mention, and is also interesting himself in the question of "range-finders," and "filters," and other necessities for naval service.
Footnote 7: Since writing this opinion I think, perhaps, it will be well to pause till the results of Professor George Forbes', F.R.S., experiments with a new stereoscopic instrument in South Africa are to hand; he is there at present by request of Lord Kitchener with his new invention. For full report of this instrument I would refer to Professor Forbes' paper read at the Society of Arts, December 18th, 1901. It is sufficient now to say that the instrument folds up to 3 foot 6 inches in length, can be used by one observer only standing, kneeling, or lying down, has great accuracy and portability, and has received the support of Sir George Clarke and other authorities.