The Evolution of Naval Armament

by Frederick Leslie Robertson

The design of the carriage was in no way influenced, apparently, by a desire to obtain a minimum area of port opening in combination with a maximum traverse of the gun. For the broad span of the front part of the carriage soon caused the gun to be “wooded” when slewed off the beam. And a further disadvantage of this broad span was in the effect it had of automatically bringing the gun right abeam every time it was hauled out after loading: the front span of the carriage coming square with the timbers of the port-sill.

As for the system of recoil, while the recoiling of the carriage with the gun had an advantage in reducing the stresses brought on the hull structure, yet this arrangement had the correlative disadvantage that the carriage as well as the gun had to be hauled out again. And, as regards safety, it is a matter for surprise that the system of chocking recoil by means of large ropes—of absorbing the momentum of a heavy gun and its carriage in a distance corresponding to the stretch of the breechings under their suddenly applied load—was not far more injurious than experience proved to be the case. Even so, the results obtained from it were far from satisfactory. “It is a lamentable truth”—we quote Sir William Congreve, writing in 1811—“that numbers of men are constantly maimed, one way or another, by the recoiling of the heavy ordnance used on board ships of war. Most of the damage is done by the random recoil of the carriage which, moving with the gun along no certain path, is much affected by the motion of the vessel and the inequalities of the deck. It is difficult to know, within a few feet, to where the carriage will come, and the greatest watchfulness is necessary on all hands to prevent accidents.” This refers, observe, to the truck gun under control. How terrible an uncontrolled gun could be, may be read in the pages of Victor Hugo’s Quatre-Vingt-Treize, of which romance the breaking loose of a piece on the gun-deck of a frigate forms a central incident. It was conjectured that the old Victory, Admiral Balchen’s flagship which went down off the Casquets in 1744, “mouse and man,” was lost through the breaking loose of her great guns in a gale.[95]

A TRUCK GUN

The accessories of the truck carriage were a source of frequent accident. The attachment of breechings and tackles to the ship’s side often involved disablement in action, the numerous bolts being driven in as missiles among the crew, who were also in danger of having their limbs caught up in the maze of ropes and trappings with which the deck round the gun was encumbered. Considered as a mechanism the whole gun-equipment was a rude and primitive affair; the clumsy carriage run out to battery by laborious tackles, the cast-iron gun laid by a simple wedge, the whole equipment traversed by prising round with handspikes—by exactly the same process, it has been remarked, as that by which the savage moved a log in the beginning of the world.

Why, then, did the truck carriage maintain its long supremacy?

The answer is, that with all its acknowledged defects it had merits which universally recommended it, while its successive rivals exhibited defects or disadvantages sufficient to prevent their adoption to its own exclusion. It was a case, in fact, of the survival of the fittest. And if we examine its various features in the light of the records of its performances in action (the truck carriage appears in the background of most of our naval letters and biographies), we shall understand why it was not easily displaced from favour with generation after generation of our officers and seamen.

In the first place the truck carriage, a simple structure of resilient elm, with bed, cheek-plates, and trunnions strongly fitted together and secured by iron bolts, was better adapted than any other form for the prevention of excessive stresses, resulting from the shock of recoil, on either gun or ship’s structure. By the expedient of allowing the whole gun equipment to recoil freely across the deck, by allowing the energy of recoil to assume the form of kinetic energy given to the gun and carriage, the violent reactionary stresses due to the sudden combustion of the gunpowder were safely diverted from the ship’s structure, which was thus relieved of nearly the whole of the firing stresses. Moreover, by allowing the gun to recoil readily under the influence of the powder-gases the gun itself was saved from excessive stresses which would otherwise have shattered it. From this point of view the weight of the carriage, relatively to that of the gun, was of considerable importance. If the carriage had been at all too heavy it would not have yielded sufficiently under the blow of the gun, and, howsoever strongly made, would eventually have been destroyed, if it had not by its inertia caused the gun to break; if too light, the violence of the recoil would have torn loose the breechings. Actually, and as the result of a process of trial-and-error continuously carried on, the weight of the finally evolved elm carriage was so nicely adapted to that of its gun that a recoil of the most suitable proportions was generally obtained, a free yet not too boisterous run back. This, of course, upon an even keel. Conditions varied when the guns were at sea upon a moving platform. With the ship heeled under a strong wind the weather guns were often fired with difficulty owing to the violence of the recoil. On the other hand the listing of the ship when attacking an enemy from windward favoured the lee guns by providing a natural ramp up which they smoothly recoiled and down which they ran by gravity to battery, as in a shore emplacement. Of which advantage, as we know, British sea tactics made full use at every opportunity.

It was strong, simple, and self-contained. Metal carriages, whose claims were periodically under examination, proved brittle, too rigid, heavy, and dangerous from their liability to splinter. Gunslides, traverses, or structures laid on the deck to form a definite path for the recoil of the gun (such as the Swedish ships of Chapman’s time, for example, carried) were disliked on account of their complication, the deck-space occupied, and the difficulty which their use entailed of keeping the deck under the gun dry and free from rotting; though beds laid so as to raise the guns to the level of the ports were sometimes fitted, and were indeed a necessity in the earlier days owing to the large sheer and camber given to the decks. The use of compressors, or of adjustable friction devices, in any form, for limiting the recoil, was objected to on account of the possibilities which they presented for accident owing to the forgetfulness of an excited crew. The truck carriage, being self-contained and independent of external adjustment, was safe in this respect.

The four wood trucks were of the correct form and size to give the results required. The resistance of a truck to rolling depends largely upon the relative diameters of itself and its axle. It was thus possible, by making gun-carriage trucks of small diameter and their axles relatively large, to obtain the following effect: on gunfire the carriage started from rest suddenly, the trucks skidding on the deck without rotating and thus checking by their friction the first violent motion of recoil; during the latter phase of the recoil the trucks rotated, and the carriage ran smoothly back until checked by the breechings.