Culture & History: Naval Warfare in the Age of Sail

493

Composed by J. B. Calvert
Last revised 9 January 2007

Theodore Roosevelt’s The Naval War of 1812 vividly made me aware of how sailing ships fought at sea, and dispelled many erroneous impressions that I had held. Among my more correct impressions is the supreme importance of maneuver. The ship could be moved only by the wind pressing on its sails or hull, by currents, by lines attached to anchors, docks, or the shore, or by oars, either sweeps of its own, or in small boats towing it. All these methods were used, sometimes desperately, to retain advantage of position, without which the ship was lost. The warship of 1800 had grown too large and unwieldy to be effectively managed by rowers. A ship sought weather gage of its enemy, so that it had freedom of maneuver, and could close if it wished. In every encounter of sail, wind and position were of supreme importance.

Next in material importance was armament. Smooth-bore cannon were the universal choice. No other invention except the wheel was better-suited to its duty, and remained less changed in fundamental nature from its inception in the 15th century, to its final disappearance in the middle of the 19th. The shock power of this instrument, on land as well as on sea, cannot be overestimated. The cannon was first of bronze, then of cast iron as this cheaper material became available. It was simply a smooth bore, closed at one end, with a touch hole drilled to the surface of the breech. It projected solid shot of cast iron or stone, later also bags of musket balls or grapeshot, and even lengths of chain, and other inventive loads for special purposes. Iron shot could be heated red-hot in a furnace to cause fires when embedded in a wooden hull or palisade. A shell was a hollow ball filled with powder and provided with a fuze that would be lighted when the shell was fired, sputtering as the shell flew, and finally setting off the powder, shattering the casing. This was purely an antipersonnel load. To fire a cannon, the bore was first swabbed with water to extinguish any sparks that would make loading unsafe. A measured quantity of gunpowder was then poured into the bore, and rammed down behind a wad of some material. A small amount of powder was also poured down the touch hole. The load was then rammed onto the wad. The gun was set to bear, and a match (a glowing stick called a slow-match was popular) touched to the touch-hole. A flash, a boom, a cloud of smoke, and the load was sent on its way at the speed of sound. The gun recoiled, hurling its mass backwards against any restraint provided. A gun rigidly mounted had to be very well mounted indeed, to prevent destruction of its mount. By 1800, the match had been replaced by some kind of lock that ignited the powder in the touch hole (or other kind of fuse) by a spark when a lanyard was pulled. Also, the powder, wad, and load could be pre-measured and packed in bags or cartridges to make loading faster. The phrase ‘to spike a cannon’ meant to disable it by driving a tapered wrought iron plug, or spike, down the touch hole with a hammer until it was level and firmly embedded. I suppose the spike could eventually be drilled out, but tools to do this were not readily available, and the process would take some time.

A gun was rated according to the weight of solid cast-iron shot that it threw. Since cast iron weighs about 450 pounds per cubic foot, this also gave the diameter of the cannon’s bore. For example, a 32-pounder had a bore of about 6 inches, a 24-pounder about 5-1/2 inches (the actual bore seems to be 5-7/8″). The weight of shot is proportional to the cube of the bore diameter, of course. Also important was the caliber, or ratio of the length of the bore to its diameter. A long gun had a caliber of perhaps 15 (I do not have accurate information on this point), and an extreme range of about a mile. An example of a long 32 is shown at the right. It was preferentially used, however, at half pistol-shot or 100 yards in broadsides of up to a ton of iron. In the late 18th century, a type of cannon well-suited to such broadsides, the carronade, was introduced. It was of smaller caliber, less than 10, which allowed a large bore that could be filled with anything on hand. The gun was lighter and shorter than a long gun, which meant that it could be used on upper decks, and more could be mounted. A 32-pounder carronade is shown at the left.

Cannon were principally placed in rows along the sides of the ship, on the gun deck or decks, and fired through ports in the side of the hull that could be stopped when not in use. They were on wooden carriages with four small wheels, and restrained by block and tackle in recoil. Powder was brought to them as needed from a magazine deeper in the ship where it was safe from fire and sparks. The armament was primary in the rating of ships. Ships were rated by number of decks, number of guns, or hull volume. By decks was meant gun decks. A single-decker, or frigate, had one gun deck (in the hull) covered by a weather deck, which most people would think of as the deck. A ship of the line had three decks, usually a deck of long guns, then two decks of carronades. A razee (from French, rasée, shaved) had had the top gun deck removed, so that it was now a two-decker and easier to handle and man. The number of guns was generally the conventional total number of guns firing through gun ports in the sides of the ship, so was an even number. There were actually more guns on a ship than this. Not included were bow and stern chasers, cannon, often on swivels, that fired forward and backwards, respectively, extra guns on the quarters, and guns that stuck through odd holes, as well as guns on the weather deck.

Rockets and torpedoes had also been introduced, but were not counted with a ship’s armament. Rockets had very poor accuracy and range, but were fearsome. Torpedoes were regarded as underhand and cowardly, since they struck a ship under the water line by surprise. They were also very effective, if they reached their targets. In 1812, neither weapon seems to have been used in ship-to-ship combat.

Hull volume is tonnage. A ton is nominally 100 cubic feet, but the tonnage of a ship is arrived at by multiplying together certain measurements, and making certain assumptions and allowances, so that it can be significantly different from the actual volume of the hull, especially in unusual ships. American practice at the time of the War of 1812 was to measure the length and maximum width, then multiply together the length less 3/5 of the width, the width, and half the width (representing the depth of the hull), and divide by 95, all measurements in feet. The large American frigates measured about 1600 tons.

HMS Victory, Nelson’s flagship, was a three-decker ship of the line, a 104. The typical ship of the line of 1812 was a 74, with a deck of long 32-pounders, and two decks of carronades, plus chasers and other miscellaneous armament. USS Constitution was classed as a 44, with a broadside of 32 long 24-pounders, 20 32-pound carronades, and two long 24’s as bow chasers, actually 56 guns. The more common frigate, such as HMS Shannon, was a 38, carrying long 18-pounders. Most ships of this period also had carronades; those with only carronades were at a disadvantage at long range and in good weather. Both the American and Royal navies made the mistake of too much reliance on carronades as primary armament. All these large ships were ship- or square-rigged on three masts. The masts were made up of three parts, a sturdy lower part well fixed in the hull, a topmast spliced to it, and a topgallant mast spliced to that. The upper parts of the masts were often torn off by gales or gunfire, and could be replaced from spares carried on the ship. Hundreds of men were required to man the sails and the guns; a crew of 300 was not unusual on a frigate.

Brigs and brigantines were smaller, two-masted ships, handy smaller versions of frigates. The brig was square-rigged on both masts, the brigantine was schooner-rigged on the mainmast. They had perhaps 22 guns. They had to be nimble sailers to stay out of trouble; their mobility and speed were their chief advantages. They were especially useful as commerce raiders, and were favored by the more prominent privateers. Leaving port, they would be stuffed with men to man the prizes they took during their cruise.

Sloops of war were single-masted ships, fore-and-aft (schooner) rigged, mounting a few guns, often on swivels, and relying on their speed and surprise for their effectiveness. They were used in cutting expeditions, where men in boats would sneak up on a craft and take it by boarding.

Now we can discuss tactics. The famous sort of naval warfare is the combat of fleets, ships of the line and their attendants. The line was the usual formation, one large ship behind the other, which gave the name to ships of the line. Faster small ships reported the location of the enemy fleet and its movement, and weather was all-important at this stage. Each line wanted to cross in front and upwind of the other, to cross the T as it was called, so that each of its ships could discharge in its turn raking fire on the enemy fleet.

By raking fire is meant fire at the bows or the stern of a ship. The ship is weaker at these points, since the sides are heavily and solidly timbered to resist heavy broadsides. There are only the chasers to contend with in these directions. In fact, some ships were built with guns in the stern specifically to counteract raking fire.

Each admiral did his best, considering the weather and his ships, to prevent the other from crossing the T, and eventually the battle developed into ship-on-ship encounters. These large battles were very rare, because they were very costly in every way. Victory could be claimed only when one side destroyed enough ships of the line of its adversary that its own ships of the line would dominate the sea.

Roosevelt’s examples demonstrate clearly that, other things being equal, superior force – that is, guns – always prevailed. In an encounter of two ships, the stronger would always win unless some other factor intervened. It was never a gamble. Any ship of the line could defeat any frigate, any frigate any brig, any brig any sloop, and any sloop any gunboat. A smaller ship relied on its speed or ease of handling to escape from an adversary. Battle was offered only when both commanders judged the chances about equal. Then, the issue depended on leadership, seamanship, gunnery, bravery, and discipline. This is the reason that famous battles are always between ships of approximately equal power, not that big ships did not pick on small out of some sense of fairness. If the small ship could not get away, it was lost.

A squadron of ships could, of course, change the odds. USS President, after it had been crippled by running aground leaving New York, was given up by Commodore Decatur to the 18-pounder frigate HMS Pomone in the battle off Sandy Hook. The Pomone was part of a blockade squadron led by the razee HMS Majestic, 56, that included a heavy frigate and two light frigates. This action is described by Roosevelt, and is very instructive. The outcome was never in doubt, however.

The lookout at the mainmasthead searched the horizon for the first appearance of the tops of sails. Reliable identification of the ship sighted was essential. It could be a ship of inferior force, perhaps a merchantman, that could easily be made a prize; it could be a ship of the line, and if an enemy, something to flee with all haste. Eventually, the hull appeared above the horizon, and the guesses could be improved. Of course, the other ship was doing the same thing. Ships did not, in time of war, carry obvious identification. In fact, they often carried false identification, if any. When the decision was made to attack and not to run, a ship raised its ensign and opened fire.

The combat between two ships began at long-gun range, although there was no hope of anything but random damage at this distance. When the ships had maneuvered closer, to within a few hundred yards, fire was directed high to tear away the rigging and topmasts of the adversary, removing his ability to maneuver. Within two hundred yards, broadsides into the hull, or raking fire, if possible, began. The solid shot did horrible deeds among the gun crews and sailors on deck. Red-hot shot set fires and searched out powder storage. This damage was said to be between wind and water. It was more difficult to hole a ship below the water line, because shot would bounce from the surface of the sea rather than entering it. It was, occasionally, done, however. If a glowing cannonball found the magazine, the ship was gone in seconds. As the ships neared, snipers in the masts brought down their enemies by musket fire, especially officers if they could be found. Heroism demanded that the officers be on deck in full uniform, of course, so they fell.

Many battles ended in desperate hand-to-hand combat when one side decided not to strike its ensign, which was a sign of surrender. If the force was very uneven, colors were struck as soon as the determination of the aggressor became evident, and there was no shame associated with the action. Only when the outcome was in doubt was fighting taken to the extreme.

This form of sea warfare was brought to an end in 1860, when the iron battleship HMS Warrior was launched. The internet site about this ship is excellent and complete, and I highly recommend it. You might contrast it with the minimal site for USS Constitution, with its deplorable backlit partial photograph. Warrior was unusual in every important respect. Its powerful engines allowed it to chase faster than any sailing ship, regardless of the weather. It had screws, not paddles, that were safe from damage. Its 110-pounder rifled, pivoted Armstrong guns could outrange any other gun in existence, and penetrate any hull. They were as new and experimental as the ship, and had a few problems that were soon corrected. The old guns were, by the way, sold to the Confederacy. Like earlier ships, Warrior was fully square-rigged, and had a broadside of muzzle-loading 68-pounders. Both these features were completely superfluous, the sails only saving a little coal on cruises. Even the 8 Armstrong guns on the gun deck were supernumerary, since the two on the weather deck could do the job. For a few years, Warrior could, single-handedly, if properly supplied and time permitted, send to the bottom of the ocean all the other navies of the world, not only the wooden sailing ships and wooden steam frigates, but the few ironclads and monitors as well. It needed simply to run down the monitors with its ram. Tests carried out shortly after launching proved that no other gun (even its own Armstrongs) could penetrate its side armor. However, Warrior never saw serious action, since it was supreme only in a time of peace. Its survival is due to its wrought-iron hull; a steel hull would long ago have rusted away. USS Constitution is practically all restoration; only the keel is claimed to be original. Wooden ships do not, in fact, last very long floating unless the timbers are constantly renewed, so those that are preserved are like grandfather’s axe, which has had nine handles and four heads.

Well, these are my reflections upon reading Roosevelt, and I really think he was quite fair. Both British and American historians of the War of 1812 were bitterly partisan and invariably garbled, and he points this out very clearly. I noticed that he commented that American solid shot was 7% lighter than British iron, that powder was sometimes poor, and that guns burst. The patriotic defense industry of the time sold the government the lowest-quality, shoddiest materials available in an atmosphere of bribery, lobbying, and cronyism, somewhat like today. Changes were made after the war. DuPont began to make reliable powder in Delaware, and West Point was cleansed of its useless staff who had produced bad officers and worse engineers. In many cases, the replacements were refugees from Napoleon’s France, and of high quality indeed, such as Mahon. The light shot and bursting guns were due to poor and impure cast iron, produced with charcoal in primitive furnaces. The US iron and steel industry had a long way to go to enter the 19th century.

The US had no line-of-battle ships until 1815 (3 were launched in that year, the Washington, Independence, and Franklin, all 74’s costing from a quarter to half a million dollars). Roosevelt’s remarks are cogent: “Had Congressional forethought been sufficiently great to have allowed a few line-of-battle ships to have been in readiness some time previous to the war, results of weight might have been accomplished. But the only activity ever exhibited by Congress in materially increasing the navy previous to the war, had been in carrying out President Jefferson’s ideas of having an enormous force of very worthless gunboats–a scheme whose wisdom was about on a par with some of that statesman’s political and military theories.” The War of 1812 is unique in that the peace treaty was very favorable, although the American conduct of the war was imbecilic and futile, both by land and by sea. Canada was not conquered, the blockade was not lifted, and the capital was captured and burnt when its militia defenders fled in all directions on the approach of a few companies of Royal Marines. The war was a total sideshow for England, of little importance beside the war against Napoleon, but was very annoying because of the exploits of the tiny American navy, the only bright spot in the picture for the US, although totally inconclusive in effect.

ABOUT THE AUTHOR

Dr James B. Calvert is Associate Professor Emeritus of Engineering, University of Denver.
Registered Professional Engineer, State of Colorado No.12317