Civil War Armor
The importance of defensive armor had ever been felt. The warriors of ancient times went to the field in coats-of-mail, and both Homer and Virgil dilate upon the exquisite carving of the shield. The hauberk and corselet were used by the Crusaders, and the chain-armor of Milan was nearly or quite impervious to the sword and spear. Mexico and Peru were won in great part by coats-of-mail. They were used until gunpowder changed the whole course of war,--and the Chevalier Bayard, that knight "sans peur et sans reproche," who had borne himself bravely and almost without a scar in a hundred battles, in his last Italian campaign, as he was borne from the field, after being struck down by a cannon-ball, mourned that the days of Chivalry were ended. And Shakspeare tells us that this villanous saltpetre had prevented at least one sensitive gentleman from being a soldier.
In the naval contests of the 18th century armed ship's tough oak sides were not easily pierced by the six- and nine-pound balls then in general use, and twelve-pounders were considered of unusual dimension. During the war between France and America, a merchantman, armed with nine-pounders, actually beat off a sloop-of-war and several Spanish privateers; but by the mid-19th century frigates, and even sloops-of-war, were armed with Dahlgren guns of eight- to eleven-inch bore, which throw balls of sixty to one hundred pounds, -- also with superior rifled cannon. Whitworth and Armstrong guns are in use that throw shot or shell distances of three to five miles, which "the wooden walls" of neither England nor America were able to resist.
The earliest experiments upon the power of iron plate to resist the force of cannon-balls appear to have been made in France by M. de Montgery, an officer in the French navy, as far back as 1810. He proposed to cover the sides of ships with several plates of iron, of the aggregate thickness of four inches, which he alleged would resist the force of any projectile. But Napoleon had not confidence in his navy; he had lost the battles of the Nile and Trafalgar; ever successful on the land, his ships had been swept by Nelson from the deep; and he had neither time nor disposition to investigate new plans for the restoration of the navy, or even to take up Fulton's new discovery. It was reserved for the third Napoleon to develop the original idea of a Frenchman, and thus to place France on the sea nearly or quite upon a footing with England.
With the improvement of cannon the importance of plate-armor became more and more apparent; and at length Mr. Stevens, under the sanction of the US Government, instituted a series of experiments upon iron plates, and soon after commenced building an immense floating battery for the defence of New York, at Hoboken, which was never finished.
Robert Stevens belonged to one of the best known and most powerful families in America. Carlyle's oft-quoted term, "Captains of Industry," may fittingly be applied to the Stevens family. Their Hoboken shops were easily the largest and bestequipped in the Union when in 1838 patriarch John Stevens died at the age of ninety. The four brothers, John Cox, Robert Livingston, James Alexander, and Edwin Augustus, worked harmoniously together. The youngest of these brothers, Edwin Augustus Stevens, dying in 1868, left a large part of his fortune to found the Stevens Institute of Technology, afterwards erected at Hoboken not far from the old family homestead on Castle Point. The mechanical star of the family, however, was the second brother, Robert Livingston Stevens. For a quarter of a century, from 1815 to 1840, he was the foremost builder of steamboats in America, and under his hand the steamboat increased amazingly in speed and efficiency. Robert designed and projected an ironclad battleship, the first one in the world. This vessel, called the Stevens Battery, was begun by authority of the Government in 1842; but, owing to changes in the design and inadequate appropriations by Congress, it was never launched. It lay for many years in the basin at Hoboken an unfinished hulk. Robert died in 1856. On the outbreak of the Civil War, Edwin tried to revive the interest of the Government, but by that time the design of the Stevens Battery was obsolete, and Edwin Stevens was an old man. So the honors for the construction of the first ironclad man-of-war to fight and win a battle went to John Ericsson, that other great inventor, who built the famous Monitor for the Union Government.
Stevens, in the course of his experiments, made the important discovery, that a single plate of boiler-iron, five-eighths of an inch in thickness, and weighing less than twenty-five pounds to the superficial foot [Sheet-iron plates of one inch in thickness weigh forty pounds per superficial foot], when nailed to the side of a ship, was impenetrable by shell and red-hot shot, the two missiles most dangerous to wooden walls. When a solid shot strikes the side of a wooden ship, it passes in and usually stops before it reaches the opposite side. The fibres of the wood yield and close up behind it, and it often happens, from the reunion of the fibres, that it is difficult to find the place perforated by the ball, and if found, it is often easy to remedy the injury by a simple plug.
But if a red-hot shot enter the ship, it may imbed itself in the wood or coils of cordage or sails, or reach the magazine, and thus destroy the whole structure, while the shell may explode within the ship and carry destruction to both men and vessel. If, then, the iron-plate had answered no other purpose, the discovery by Stevens of its capacity to resist the two most formidable weapons of his day would alone have been of great value to the country; but he went farther, and demonstrated by actual construction the idea of Montgery, that successive plates of iron would resist the cold spherical shot thrown by the best artillery, and his floating battery or frigate is protected by plate within plate of iron armor.
In 1854, Napoleon, who had long studied the art of war, and during his stay in New York had doubtless seen or heard of the floating battery, determined to construct two such batteries, and accordingly built the Lave and Tonnerre. With one of these, the Lave, during the Russian War, he assailed and destroyed in the brief space of one hour the strong fortress of Kinburn, near Sebastopol; and in striking contrast to this success, a large British steamship, heavily armed, but constructed of wood, was actually captured near Odessa by a small party of Russians with two or three thirty-two-pounders worked through a gap in an embankment.
The invulnerable battery of France anchored close under the fortress. Before its cannon, granite walls are shivered into fragments most dangerous to the gunners, while the shells, burying themselves two or three feet deep in the brickwork, by their explosion shake the walls to pieces. Iron, protected by iron, triumphed over both bricks and granite, which had defied the fleet of England.
The Emperor was not slow to realize the result of the problem he had solved. He at once proceeded to test the strength of the best kinds of plate made in his dominions, and found, by actual trial, that plates of the best iron, but four and three-fourths inches in thickness, were able to resist repeated shocks of solid balls fired at the distance of twenty metres (less than four rods) from his sixty-eight-pounders, and from rifled guns throwing shot of nearly the same calibre,--and this, too, when the balls were impelled by more than one-fourth their weight of powder. But ships rarely engage at such close quarters either with vessels or fortresses, and the effect of the ball is greatly diminished by distance, a single inch plate sufficing to stop a spherical shot at a long distance.
As the result of these experiments, the Emperor proceeded to construct the Gloire, an iron-clad frigate, which made several voyages, was tried in a severe gale, and ran from Toulon to Algiers in the brief space of sixty-six hours.
The Gloire was a steam-frigate cased in five-inch plates; she was two hundred and fifty feet in length by twenty-one in width, mounted thirty-eight rifled fifty-pounders, is moved by engines of nine hundred horse-power, was manned by six hundred men, had a speed of twelve and a half knots, and a capacity for five days' coal,--a capacity which might be easily increased by a little more breadth of beam, but which is sufficient for a passage to Algiers, or along the coast of Spain, England, or Italy. This vessel was considered invulnerable by balls discharged from rifled cannon at the distance of four hundred yards. Encouraged by his continued success, the Emperor at once ordered the construction of nine such frigates.
During the contest with Russia, England would not venture to expose her wooden ships of the line to the close fire of the batteries either at Cronstadt or Sebastopol, and found it safer to shell them at a respectful distance and with indifferent success. She was deeply impressed, however, with the performance of the Lave and Tonnerre at Kinburn, and seriously disturbed by the completion of the great naval station at Cherbourg, armed with more than three hundred cannon, and directly opposite her coast.
England at first sought to meet the new invention by improved artillery, and produced the Whitworth and Armstrong cannon, which had a range of four to five miles. With these she practised at short distances upon targets of strong oaken plank faced with iron plates of four to five inches in diameter, but found the plates impervious to balls, and vulnerable only by steel bolts of small diameter, fired at short distances from Whitworth and Armstrong cannon, -- bolts so small that the wounds they made in the frames faced with iron usually closed or did little mischief. A few plates of inferior iron occasionally gave way after repeated assaults, for English iron was coarsely made and poorly welded.
England was at length convinced; she determined that she could not safely permit the Emperor of the French to rule the sea with his iron navy. She had not forgotten St. Helena. She realized that she had no fleet that could safely encounter one of his mail-clad warriors, and found herself obliged to copy the new invention. She commenced ten iron-clad ships of the line. But she could not tamely copy France. Instead of confining herself to the length of the Gloire, she constructed vessels of immense size. The Warrior, recently launched, is four hundred and twenty-six feet in length, nearly fifty-two feet in depth, has a width of fifty-eight feet, measures six thousand one hundred and seventy-seven tons, and is moved by engines of twelve hundred horse-power. She mounted thirty-six cannon of the largest class, and her armor weighs nine hundred tons.
This vessel was a formidable antagonist upon the open sea; but her great depth, with the weight of her armor, caused her to draw thirty feet, which would prohibit her entrance into most seaports. She was vulnerable, too, at each extremity. Her iron plates, four and a half inches thick, extended but half her length, leaving more than a hundred feet at each end covered by a plate of only five-eighths of an inch in thickness; and in case these portions should be injured, she must rely upon her water-tight compartments
The importance attached by England to armor-clad steamers may be inferred from the debates in the House of Lords on the 11th and 14th of June, 1861, in which it was officially stated that the Government had not authorized the construction of a single wooden three-decker since 1855, nor one wooden two-decker since 1859, although it had launched a few upon the stocks for the purpose of clearing the yards,--and that it now contemplated culling down a number of the largest wooden steamships of the line for the purpose of plating them with iron, while it was constructing nothing but iron ships, except a few light despatch frigates, corvettes, and gun-boats.
The advantages of armor had been already demonstrated on the French ship "Gloire" and others in connection with the naval part of the Crimean War, and there was a feeling that ironclads of some kind were a necessity of the situation. These facts were perhaps more clearly realized at the South than at the North; and early in 1861 we find Mr. Stephen R. Mallory, the Confederate Secretary of the Navy, taking active steps to raise the "Merrimac," which had been sunken at the Norfolk Navy Yard, and convert her into an armor-clad.
Information regarding this project naturally became known to the Federal authorities, and occasioned President Lincoln and the entire Cabinet the most serious anxiety. At length on August 3, 1861, the appointment of a Board was authorized, the duty of which it should be to examine into the question fully, obtain plans, and recommend the construction of such armor-clads as they should judge best suited to the demands of the situation.
The Confederates showed the same skill and energy in building their great ironclad rams as the men of the Union did in building the monitors which were so often pitted against them.
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