Warfare through the ages has been driven by the measure-countermeasure struggle between armor and armament.
Sometimes a breakthrough significantly shifts the balance one way or the other and changes warfare at least temporarily. Castles and armor dominated for a while but were driven into obsolescence by gunpowder. In our own era we’ve seen the tank reign supreme (World War II), have it’s death proclaimed with the advent of the man-portable guided missile and shaped charge (the Sagger missile during the Yom Kippur War) and then reemerge to dominate the battlefield thanks to the high velocity smoothbore cannon, reactive armor, and other advances in armor (the M1 Abrams).
The same saga played itself out at sea where naval architects had to deal in the assorted trade offs of weight distribution, handling, and the tensile strength of their basic construction material, wood.
By the late 18th century naval design was nearly at a stalemate. To a certain extent it seem like the final word in ship design had been spoken by the French with the creation of the 74-gun ship of the line. This platform maximized armament and sailing characteristics and after the first was captured by the British captured Invincible at Cape Finisterre it’s design quickly dominated the British navy.
The design of warships, oddly enough, was driven by metallurgy as much as naval architecture. To be able to penetrate the two-feet or so thickness of the sides of a ship of the line a ship had to carry a main battery of at least 24-pounders, the gun alone weight two tons. Aboard first rates, the main battery would be 32-pounders weighing nearly 2 3/4 tons. When one considers the armament of HMS Victory at Trafalgar, she had 30 32-pounders and 28 24-pounders. When the weight of carriages was included this was over 170 tons. On top of that was the smaller armament of 12-pounders, if anything weighing 3800 pounds could be classed as small, where the weight of weapons alone topped 270 tons. All of this produced a broadside weight of 1000 pounds, a fraction of a percent of the weight of the ordnance.
Serving the artillery was very labor intensive. To serve the larger guns required a crew of 14 on half the guns and a half crew on the other half. This adds at least an additional 2000 pounds of weight per pair of guns.
In order to carry the weight and bear the recoil of these guns, decks and bulkheads had to be reinforced. Adding more weight and reducing sailing characteristics. It was fairly common for a ship of the line with the weather gage to have to fight with the lower gun ports shut to prevent the ship from swamping.
By the time of the advent of the 74-gun ship of the line the necessity of carrying increasingly larger guns had resulted in a near stalemate afloat. Despite what novelists would have us believe, the fleet actions in the latter half of the eighteenth century were not particularly sanguinary affairs. For instance, in the Battle of the Chesapeake (featured in the Alan Lewrie novel, The French Admiral) 24 French ships of the line blazed away at 19 British ships of the line for 2 1/2 hours. In the end neither side lost any ships, the French lost 209 men killed or wounded to the British losses of 336.
All of this changed in 1779 when the Navy Board prevailed over the objections of the Ordnance Board and began outfitting ships with the carronade.
The design was based on the simple principle of reducing the weight of the gun by reducing the internal pressure to which the gun tube were subjected. He did this by reducing the length of the barrel, thereby decreasing the length of time the tube was under pressure, and the powder charge. He compensated for this by firing a hollow shot, this allowed for a higher powder charge per weight of shot than with solid shot, and by reducing the windage, or the difference between the bore of the gun and the diameter of the shot.
As a result a long 24-pounder weighing, gun and carriage, 5,600 pounds could be replaced by a 68-pounder carronade, weighing 4760 pounds. The full crew dropped dramatically from 14 to 5 men.
Unlike the long guns which had to be trained by levering the carriages with handspikes and which, if trained too far from the center line, could break their breeching cables, the carronades were mounted on a pivoting mount. One of the unspoken advantages is apparent in the picture at the top of this story. When not in use the carronade could be pivoted parallel to the gunwales of the ship freeing up much more deck space for work and leisure.
We’ll be talking more about the carronades debut on active duty in further installments.