A monitor was a relatively small
The original monitor was designed by
The term "monitor" also encompasses the strongest of riverine warcraft, known as
In Latin, a monitor is someone who admonishes—that is, reminds others of their duties—which is how USS Monitor was given its name.[
At no great distance from the Minnesota lay the strangest-looking craft I ever saw. It was a platform of iron, so nearly on a level with the water that the swash of the waves broke over it, under the impulse of a very moderate breeze; and on this platform was raised a circular structure, likewise of iron, and rather broad and capacious, but of no great height. It could not be called a vessel at all; it was a machine—and I have seen one of somewhat similar appearance employed in cleaning out the docks; or, for lack of a better similitude, it looked like a gigantic rat-trap. It was ugly, questionable, suspicious, evidently mischievous—nay, I will allow myself to call it devilish; for this was the new war-fiend, destined, along with others of the same breed, to annihilate whole navies and batter down old supremacies. The wooden walls of Old England cease to exist, and a whole history of naval renown reaches its period, now that the Monitor comes smoking into view; while the billows dash over what seems her deck, and storms bury even her turret in green water, as she burrows and snorts along, oftener under the surface than above. The singularity of the object has betrayed me into a more ambitious vein of description than I often indulge; and, after all, I might as well have contented myself with simply saying that she looked very queer.
Going on board, we were surprised at the extent and convenience of her interior accommodations. There is a spacious ward-room, nine or ten feet in height, besides a private cabin for the commander, and sleeping accommodations on an ample scale; the whole well lighted and ventilated, though beneath the surface of the water. Forward, or aft (for it is impossible to tell stem from stern), the crew are relatively quite as well provided for as the officers. It was like finding a palace, with all its conveniences, under the sea. The inaccessibility, the apparent impregnability, of this submerged iron fortress are most satisfactory; the officers and crew get down through a little hole in the deck, hermetically seal themselves, and go below; and until they see fit to reappear, there would seem to be no power given to man whereby they can be brought to light. A storm of cannon-shot damages them no more than a handful of dried peas. We saw the shot-marks made by the great artillery of the
Merrimackon the outer casing of the iron tower; they were about the breadth and depth of shallow saucers, almost imperceptible dents, with no corresponding bulge on the interior surface. In fact, the thing looked altogether too safe; though it may not prove quite an agreeable predicament to be thus boxed up in impenetrable iron, with the possibility, one would imagine, of being sent to the bottom of the sea, and, even there, not drowned, but stifled. Nothing, however, can exceed the confidence of the officers in this new craft. It was pleasant to see their benign exultation in her powers of mischief, and the delight with which they exhibited the circumvolutory movement of the tower, the quick thrusting forth of the immense guns to deliver their ponderous missiles, and then the immediate recoil, and the security behind the closed port-holes. Yet even this will not long be the last and most terrible improvement in the science of war. Already we hear of vessels the armament of which is to act entirely beneath the surface of the water; so that, with no other external symptoms than a great bubbling and foaming, and gush of smoke, and belch of smothered thunder out of the yeasty waves, there shall be a deadly fight going on below—and, by and by, a sucking whirlpool, as one of the ships goes down.
Three months after the Battle of Hampton Roads, John Ericsson took his design to his native Sweden, and in 1865 the first Swedish monitor was built at
Motala Warf in
Ericsson and others experimented greatly during the years of the American Civil War. Vessels constructed included a triple-turreted monitor, a class of
In the 1860s and 1870s several nations built monitors that were used for coastal defense and took the name monitor as a type of ship. Those that were directly modelled on Monitor were low-freeboard, mastless, steam-powered vessels with one or two rotating, armoured turrets. The low freeboard meant that these ships were unsuitable for ocean-going duties and were always at risk of swamping, flooding and possible loss. However, it greatly reduced the cost and weight of the armour required for protection, and in heavy weather the sea could wash over the deck rather than heeling the ship over.
Attempts were made to fit monitors with sails, but the provision of masts interfered with the turrets' ability to operate in a 360-degree arc of fire and the weight of masts and sails aloft made the ships less stable. One ship,
A late example of a vessel modeled on Monitor was BAP
BAP Huáscar, under the command of Rear Admiral
Over the years, both Chile and Peru came to venerate the ship and the officers from both sides that died on her deck, either commanding her or boarding her, as national heroes. Huáscar is currently commissioned in the Chilean Navy, has been restored to a near-original condition and, as a
In an effort to produce a more seaworthy vessel that was more capable in ship-to-shore combat, a type called the
Monitors were used frequently during the