Sailing Into the Wind: The Steam Powered Warships

^{National Archives}

^{U.S. steam frigate Pensacola in 1861.}

For thousands of years, most mariners had dreamed of being able to take a large cargo anywhere they wanted without worrying about wind and currents.

High‑ranking British naval officers in the 19th century were the exception. We’ll come to that in a moment.

Ships propelled by oars could, of course, proceed into the wind (although progress was a lot slower than if there were no wind), but the large number of rowers precluded carrying much cargo and ensured that such ships as the Greek triremes (a galley with three banks of rowers) could not go far from land. Primitive sails like those of the classical galleys or the Arab dhows could take a vessel a long distance if the wind were favorable, but not if it were in the wrong direction. That’s why a dhow plying the Indian Ocean trade took a year to make a round trip. Half of the year the winds blew to the West; the other half, to the East. Scandinavian seamen learned to manipulate a square sail to allow some progress against the wind, as did Arab sailors using the lateen sail. But even after Europeans developed the full‑rigged ship, progress could be slow unless the weather cooperated. If there was no wind, progress was nil.

The steam engine changed sailing radically, and that transformed warfare at sea. But the steam engine would not have been possible without a previous advance in the art of war. In the 18th century, a Swiss gunfounder named Jean Maritz, improved the rough, sometimes‑crooked bores of cannons by inventing a machine for boring out the barrel after the gun was cast solid, instead of incorporating the bore in the casting. A few years later, in 1774, a British engineer named John Wilkinson improved the machine. Wilkinson’s device created an extremely smooth and precise hole. With a machine like that, the pioneers of steam power were able to build cylinders with tight‑fitting, efficient pistons.

Such cylinder and piston arrangements are essential to early steam engines as well as modern internal combustion engines.

The first steam engines worked by filling a cylinder with steam, then con‑densing it to water. The vacuum created drew the piston into the cylinder. These “atmospheric” engines were useful for pumping out mines and other tasks where their weight was not important. They were far too heavy and bulky to use aboard ships, however. James Watts’s improved steam engine drove the piston in the opposite direction – expanding steam, rather than atmospheric pressure on a vacuum was the driving force. Such engines could be made small enough to power a ship. Their earliest use was to turn a pair of huge side wheels.

Steam gave navies a great strategic advantage. Steam warships no longer depended on weather and could cross the oceans much faster than sailing ships.

“Seizing the weather gauge” (maneuvering into the best location to take advantage of the wind) had long been a favorite tactic of British seamen. It no longer gave any advantage. For that reason, Britain, although it was the home of the first steam engines and it utterly depended on its navy for its primacy in world affairs, tried to retard the development of steam‑powered ships. British naval personnel were the most skilled in the world; British shipyards devoted to building sailing men‑of‑war were the biggest in the world; British technology in preserv‑ing food for long journeys, manufacturing the heavy, short‑range cannons, called carronades, and everything else needed for wooden, sail‑driven warships, led the world. If the world’s navies went to steam, all of that would be worthless.

In 1828, the British admiralty expressed their views on steam‑powered warships:

Their lordships feel it is their bounden duty to discourage to the utmost of their ability the employment of steam vessels, as they consider that the introduction of steam is calculated to strike a fatal blow at the naval supremacy of the Empire.

In spite of the size of the British Navy, this policy bore more than a little resemblance to the actions of an earlier British authority figure: King Canute, who tried to tell the tide to reverse itself. The American, Robert Fulton, had built a working steam ship as early as 1807. In 1837, the paddle wheel steamer Sirius crossed the Atlantic in 18 days – breathtaking speed in an era when Atlantic crossings were measured in months.

Although the new method of propulsion had manifest advantages, the world’s navies did not immediately board the steamship. The French started building steam warships in the 1840s, but they did so on a small scale. There were a number of reasons for this slow progress. There was the natural conservatism of sailors and military men, and that the British, owners of the world’s most powerful navy, professed to see little value in the new technology. And, most important, there was the fact that the early steamships could not survive a battle with sailing warships of comparable size. The huge paddle wheels on each side of the vessel were vulnerable to gunfire, and they made it impossible for the ship to carry enough cannons along the side to match the broadsides of a sailing ship. Another drawback was that steamships could not stay at sea nearly indefinitely, as the sailing ships could. They had to be near a supply of coal.

The paddle wheel was the first drawback eliminated. In its place, ship builders used the screw propeller. The new device had to rotate much faster than a paddle wheel, which meant both major changes in gearing and much more efficient engines. John Ericsson, a Swedish engineer, invented both a screw propeller that worked and an engine to drive it. He sold the designs to the U.S.

Navy, and in 1842 the U.S.S. Princeton became the world’s first screw‑propelled steamship. Princeton’s engine and drive shaft were located below the waterline for protection, and the ship was able to carry enough guns for a broadside. In 1843, the British steamer Great Britain became the first screw‑equipped ship to cross the Atlantic.

The age of steam had arrived. Ship builders were still hedging their bets by equipping their vessels with masts and rigging that could be used if the engine failed, but it was hard to navigate a paddle wheeler using sails alone. Screw propellers made sailing easier, but even the propeller caused interference.

The next major improvement in warships was adding armor (something we’ll look at in the next chapter). Another huge advance in steam engines after the introduction of armor was the steam turbine engine, which used a spinning wheel turned by rapidly expanding steam to propel the vessel. These engines made possible the high‑speed torpedo boats that threatened the supremacy of the battleship at the turn of the 19th and 20th centuries. At the British Jubilee Naval Review in 1897, the steam launch Turbinia stole the show as it dashed in and out of the line of battleships at the unheard‑of speed of 34 1/2 knots. We’ll have another look at these torpedo boats in Chapter 26 on the “locomotive torpedo.”