From the mid-16th century until the Napoleonic Wars the function and design of guns changed very little, with ordnance consisting of a simple metal tube down the muzzle of which was rammed a charge and round ball. The charge was then ignited by a fuse that communicated with the powder down a vent at the breech, at the top rear of the gun.
Long guns and carronades
In the 1780s foundries ceased to manufacture guns from brass and began to cast from a stronger and more reliable material, iron, which made it possible to produce guns as one solid piece which could then be bored out, thus creating stronger barrels less likely to explode. Naval ordnance was classified according to the weight of the round shot it fired. Thus, in straightforward fashion, an 18-pdr fired an 18lb ball. Frigates and ships of the line also carried 24-pdr and 34-pdr guns, with the heaviest ordnance always arrayed on the lowest gundeck to ensure the stability of the ship.
The carronade was invented by General Robert Melville in 1752 at the Carron Iron Works and first manufactured for naval service in 1779. It had a shorter barrel than an ordinary 'long gun' and used a smaller powder charge to fire a heavy short, up to 64lb in weight. The carronade came into use in the Royal Navy during the War of American Independence (1775-83) and thereafter became standard on the quarterdecks of frigates and as the main armament of sloops and brigs. These weapons could produce a crushing broadside if fired at very close range, and their low velocity tended to produce great clouds of deadly splinters upon striking the enemy's hull, as opposed to penetrating it. The carronade was mounted on a slide rather than on a wheeled carriage and could fire case or grapeshot as an anti-personnel weapon - highly effective in clearing the enemy deck.
In the last years of the Napoleonic Wars, carronades were withdrawn from newly built smaller ships and replaced by standard ordnance.
Chase guns, swivel guns and rockets
Considerably smaller in calibre than the carronade was the chase gun or 'chaser', mounted on the bow to fire forward from the forecastle, and hence the name 'bow chasers', or alternatively mounted on the stern to fire from the poop or quarterdeck. These weapons fire a 6lb or 9ln shot, and were made of brass, a material which better suited small pieces of ordnance in terms of facilitating accuracy, whereas iron was reserved for standard ordnance.
Bow chasers were employed to fire at a vessel being pursued, with the intention of striking its masts or rigging, disabling it sufficiently to prevent the vessel's escape. Stern-chasers were used against a pursuing ship, with the similar intention of disabling it sufficiently to bring an end to the chase.
Swivel guns constituted the smallest form of ordnance. These were mounted on swivels so that they could fire at practically any angle. Like chasers, these served as anti-personnel weapons, loaded with lead shot and fired at close range, particularly at enemy boarders. They were often mounted on the ship's rail, but they were small enough to be carried aloft before action and, together with a gun mount, lashed dto a spar or top and used to fire down onto the enemy's deck. Swivel guns were also ideal weapons aboard ships' boats, particularly when employed against opposing boats.
Although rockets were invented centuries before in China, William Congreve, who worked at the Board of Ordnance, put them to effective military use in the West. The rocket which came to bear his name was little more than a rudimentary warhead in the form of a pointed metal cylinder filled with gunpowder, attached to a long stick to stabilize its flight. Warheads came in different varieties, depending on their purpose. Some were explosive for use against ships or troops ashore, while others were incendiary, to be used against ships, harbour facilities and coastal towns. Some contained shrapnel for use against enemy crews or formed units on shore. Rockets, like ordinary ammunition, were classified according to their weight, with the 32-pdrs and 42-pdrs being the most common. The former had a range of 3,500 yards, but they and all other rockets were wildly inaccurate and could only be depended on to fall in the general area intended. The 32-pdr rocket was made of 42inch iron cylinder, four inches in diameter, at the tip of which was fitted a conical nose. A 15ft stabilising stick was attached to the side of the cylinder. Rockets were normally fired by small boats specially fitted for such weapons, including a frame mounted on the deck in such a way as to be unencumbered by sails or rigging. Thousands of rockets were used in 1807 to destructive effect during the bombardment of Copenhagen, much of which caught fire as a result.
Types of ammunition
Various types of ammunition were used by the Navy, the most common being a solid iron ball called a round shot (the term 'cannon ball' was not in use at the time and, indeed, is merely a landsman's term which was never applied to artillery, whether on land or at sea). Gun crews could also make use of a variety of anti-personnel ammunition, including canister shot, which consisted of a cluster of small shot held together in a canvas bag or thin metal container. They could also make use of langridge, which comprised scrap metal similarly held together so that on discharge the container easily broke open and spread it's contents like a giant shotgun. Such ammunition was only effective at short range, but if fired at a crowded enemy deck when close at hand the results were devastating.
Other forms of ammunition were reserved for destroying enemy rigging or to damage, if not destroy, the enemy's masts. Chain shot, which consisted of two balls attached by metal links, could tangle or cut through lines and shred sails, thereby impeding the enemy's ability to control his direction and speed. Bar shot, which consisted of two spheres, joined by an iron bar, performed a similar function, though it was more effective than chain shot against masts and spars. The Board of Ordnance specified the number of round to be carried for each gun when a ship left port. For a ship of the line this was typically 80 round shot, three of chain or bar shot, and five of canister shot.
Hot shot was a variation of ordinary round shot, which was heated to a critical redness in a special furnace before being loaded into a gun and fired at an opposing ship or some other target vulnerable to burning. Preparing hot shot was an exceedlingly risky venture, for on a rolling ship the shot could fall from its special cradle and, in any event, finding a suitable and safe place for a furnace aboard ship was no easy matter. Hot short therefore was principally the weapon of choice of shore batteries seeking to destroy enemy ships. Loading this glowing red ammunition required special care: two men carried it in special tongs to the gun, which had been prepared with a charge protected by a damp wad, or wet clay, before being rammed home. Without this precaution, the heat of the shot could cause a premature explosion, wasting the ammunition and perhaps injuring some of the gun crew in the process. Time was also of essence, for the crew had to act swiftly by ramming a second wad in front of the shot before training the gun and firing it.
To propel these various types of ammunition, ships carried vast amounts of gunpowder, stored in the magazine. Gunpowder, properly known to contemporaries, as 'black powder', was produced from a composite of saltpetre(potassium nitrate), sulphur and fine charcoal. A process known as 'corning' converted these substances into granules of varying degrees of fineness. The largest guns used the coarsest variety, while small hand held firearms like pistols required the finest type, which was also used in priming the charges of cannon. Members of the crew made up charges for the guns in the form of cartridges, consisting of flannel or paper containers of varying sizes, depending on the weight of the powder required. Naturally, the heavier the ammunition, the greater the weight of charge needed to propel it. A full charge for a 32-pdr, for instance, required 11lb of powder. To issue a salute, which of course required no ammunition at all, only 6lb were needed.
As black powder is highly combustible, nothing more than a simple spark is required to detonate it. It therefore required special handling and was carefully stored in a magazine, or 'powder room', situated deep within the ship, far from the galley and other sources of fire or sparks. As it became useless when wet, the powder also had to be protected from water. Magazines were situated next to the 'filling room' where cartridges were prepared. The use of iron tools and equipment in or near the magazine was strictly forbidden, notwithstanding the fact that powder was storedin wooden barrel, ostensibly proof from danger. Even the barrels were bound with copped or wooden hoops, rather than the standard iron ones, to reduce the risk of catastrophe. Such was the volatility of black powder that a fire in the magazine, whether from a candle, spark, flame or enemy shot, nearly always resulted in the instantaneous destruction of the ship.
Black powder was a crude substance which when fired produced a dense cloud of white smoke which, in the absence of wind, could remain in place for several minutes, reducing visibility for the gunners and obscuring the target for both sides. It was the phenomenon that gave rise to the expression 'fog of war', though it has come to mean much more since 1815. In battle, burning grains of powder caused 'powder burns' when they settled on the men's faces, arms and hands, while the smoke would blacken their skin with unburned powder residue. The fumes created by the multiple explosions also gave the men a raging thirst and could cause severe headaches - indeed, these were unavoidable in any event owing to the loud report of the guns, together with the shouts of the men and the rolling of the gun carriages. With ships at great risk from fire and explosion, the Yeoman of the Powder Room specifically monitored the gunpowder and ensured that it was stored and handled properly. To minimise the risk of fire, the powder charges were held in cylindrical wooden containers and taken up to the gun decks by 'powder monkeys' - nimble young boys who raced up and down the ladders as rapidly as possible.
Small arms
Members of the ship's crew could make use of a variety of hand-held weapons for close action, including firearms and edged weapons. The Board of Ordnance maintained an arsenal at the Tower of London, though civilian contractors also supplied the naval service with muskets and pistols. The former consisted of a shorter version of the land pattern musket, or 'Brown Bess', which is measured 46inch in length, weighted 9lb 4oz. and fired a lead ball with a 0.75in. diameter. Muskets and pistols were not rifled, and thus suffered from the same deficiences in accuracy as their smoothbore counterparts in naval ordnance. Effective range was at best 100 yards, though across a rolling deck all but a marksman was lucky to hit a man with an aimed shot.
Writing in 1814, a colonel in the Army lamented that a musket ball:
Will strike a figure of a man at 80 yards; it may even.....at a 100, but a soldier must be very fortunate indeed who shall be wounded by a common musket at 150 yards provided his antagonist aims at him: and as to firing at a man at 200 yards with a common musket you may as well fire at the moon and have the same hope of hitting your object. I do maintain and will prove whenever called upon that no man was ever killed at 200 yards by a common musket by the person who aimed at him.
Firearms were therefore used with best effect when ships stood practically side by side or during boarding, though once discharged they were rendered little better than clubs, for there was no time in the heat of a melee to reload them. This accounts for pistols always being issued in pairs. Shore duty, of course, was another matter, and for this task sailors were quite sensibly armed with muskets and bayonets.