How the first ironclad changed world history

October 25 is the anniversary of a seminal development in the history of naval warfare. On this date 1861, workers in New York laid the keel of the USS Monitor, a craft whose launching would usher in the era of industrial age warfare.

This 987-ton armored turret gunboat saw its first action against the Confederate ironclad Virginia ((which had been built from the captured Union ship Merrimack)) in a historic engagement on March 9, 19862. The previous day, the Virginia had defeated two big Federal warships, destroying both and killing more than 240 of their crewmen. Although the battle was ruled a tactical draw, the Monitor helped preserve the Federal blockade of the Norfolk area.

Officers on the deck of the Monitor while the ship was in the James River, Virginia, July 9, 1862. The Monitor was the first warship with a 360 degree rotating armored gun turret. Its underwater hull was protected by an armored deck and belt.

Photograph by McCaffrey's Elite Photo, New York, of a depiction of the March 1862 battle between Monitor and the CSS Virginia. It was one of a series called "Merrimac and Monitor Naval Battle", that got exhibited in New York City during the 19th century.

The battle between USS Monitor and CSS Virginia at close range in Hampton Roads, Virginia, March 9, 1862 in a lithograph by Closson Blake, after a painting by W.F. Halsall.

In late December 1862, the Monitor was ordered south for further operations. Caught in a storm off Cape Hatteras, she foundered on December 31, 1862. This line engraving, "Loss of the 'Monitor' in a Storm off Cape Hatteras, December 30th, 1862, was published in "The Soldier in Our Civil War.

Crewmen relaxing on deck, while the ship was in the James River, Virginia, on July 9, 1862. Some men are playing checkers at right. Another man is reading a newspaper by the starboard smokestack.

Transverse hull section through the turret. Engraving published circa 1862, based on John Ericsson's drawings, and measurements taken from the ship.

Line engraving published in "Harper's Weekly", January-June 1862, with sketch plan of the ship and her turret, with identification of specific features.

1862 diagram showing the ship's inboard profile, plan view below the upper deck and hull cross sections through the engine and boiler spaces.

Crew members cooking on deck, in the James River, Virginia, July 9, 1862.

Watercolor by Oscar Parkes.

Line engraving published in Harper's Weekly, September 1862, depicting the launching of the Monitor at the Continental Iron Works, Greenpoint, New York, on January 30 1862. The artist may have been guilty of some embellishment as it was unlikely that the Monitor got launched with her heavy armored turret, pilothouse and other fittings already installed.

Engraving published in Harper's Weekly, March 22, 1862.

Line engraving, entitled "The Victorious Union Gunboat 'Monitor'", published by Caldwell & Co., depicts the ship as she appeared before angled plating was added to the base of her pilothouse.

A photograph of the Monitor deck looking forward on the starboard side, while the ship was in the James River, Virginia, 9 July 1862. The turret, with the muzzle of one of Monitor's two XI-inch Dahlgren smoothbore guns visible, is at left, with the armored pilothouse beyond. Note dents in turret armor (far left) from hits by Confederate heavy guns.

Watercolor in the Castello Sforzesco, Milan, Italy, circa the 1930s.

The Monitor's wreck was discovered in 1974 and is now a marine sanctuary. Here, a photo of her revolving gun turret, which was salvaged.