Grace's Guide is the leading source of historical information on industry and manufacturing in Britain. This web publication contains 138,957 pages of information and 225,312 images on early companies, their products and the people who designed and built them.
The CSS Virginia was a ironclad warship which started life as the wooden-hulled screw steam frigate USS Merrimack, laid down in 1854. Merrimack was provided with guns designed by John A. Dahlgren.
On 20 April 1861 the U.S. Navy burned Merrimack to the waterline and sank her to preclude capture. The Confederacy, desperate for ships, raised Merrimack and rebuilt her as an ironclad ram.
Stephen Mallory, Secretary of the Navy selected Merrimack for conversion into an ironclad, since she was the only large ship with intact engines available in the Chesapeake Bay area. Preliminary designs were submitted by Lieutenants John Mercer Brooke and John L. Porter.
Commissioned as CSS Virginia 17 February 1862, the ironclad was the hope of the Confederacy to destroy the wooden ships in Hampton Roads, and to end the Union blockade which had already seriously impeded the Confederate war effort.
'Iron Dawn' by Richard Snow provides an excellent account of the background to the politics and construction of Virginia/Merrimack and Monitor, with graphic accounts of their battles at sea . Richard Snow observes that Virginia was the official name, but she was more commonly referred to as Merrimack, and the alliteration - Monitor and Merrimack - has only grown more firmly fixed over time. The book also provides much of the following information.
The iron armour plates were rolled by the Tredegar Iron Works of Richmond, Virginia. Initially it was intended to have three layers of 1" thick plate backed by 27" of wood. Tests showed that this was inadequate, and another 1" layer was added. Following further tests, it was decided to call for plates to be rolled of 2" thickness. These were fitted in two layers.
Merrimack's engines were built at the West Point Foundry, New York. They were rebuilt to power the Virginia.
Virginia was provided with six 9" smooth bore Dahlgren guns and two 6.4" and two 7" rifled guns designed by Brooke.
On 8 March 1862 Virginia engaged the Cumberland and Congress. The effect on Cumberland was devastating. Virginia's own shells and shot were deflected by the sloping armour. Virginia then rammed the Cumberland, which started to sink. Even so, the crew of the Cumberland bravely continued to fire broadsides at the Virginia at a range of 100 yards, in vain. Captain Radford refused to surrender.
Virginia then turned its attention to the Congress, which surrendered after sustaining serious casualties. The Virginia then came under fire, which her crew assumed to be coming from the Congress, but was from shore-based guns. Virginia resumed firing, eventually destroying Congress. Several other vessels on both sides were also involved in the fighting. Virginia suffered some casualties, and sustained some damage, the most serious being holing of the funnel, which had a marked adveree effect on the furnace draught, and nehnce on boiler output,halving the ship's speed.
The encounter dramatically demonstrated the vulnerability of heavily-armed wooden warships when confronted by heavily-armoured adversaries.
Following this battle, the Virginia was seen to be practically invulnerable, with nothing to prevent it laying Washington to waste. Panic ensued.
Everything would depend on the USS Monitor.......
Monitor had arrived in the Hampton Roads on 9 March 1862. Virginia had just started to attack the USS Minnesota when the Monitor steamed round the Minnesota and opened fire.
This was the first engagement between ironclad warships. Neither ship sustained major damage. Following the engagement, it was determined that Monitor had been hit 22 times, including nine hits to the turret and two hits to the pilothouse. She had managed to fire 41 shots. Virginia's armour sustained 97 indentations from the fire of Monitor and other ships. The capability of both ships' armamament had been constrained: Virginia's by the limited availabiity of solid shot, Monitor's by restrictions on the amount of charge allowed to be used.