The first Agamemnon to serve in the Royal Navy (1781 - 1809) was said to be Lord Nelson's favourite ship; it was obvious therefore that when the second was launched in 1852, she would have to struggle to make a reputation for herself yet, paradoxically, she succeeded twofold, once as a ship-of-war and then as a bringer of concord.
Originally designed as an 80-gun Second Rate in 1841, the order to build her was suspended in 1844 but resurrected in 1849 as part of the wider campaign to introduce steam power into the predominantly sailing battlefleet. Selected as the nameship for a class of five 91-gun screw two-deckers, the new Agamemnon was laid down in Woolwich Dockyard in November 1849 and was launched on 22nd May 1852. Measured at 3,085 tons, she was 230 feet in length with a 55 foot beam and could steam at 11¼ knots propelled by her 600nhp. engine. Completed on 27th March 1854 at a total cost of £141,299, she had two decks bristling with guns of varying calibre and one massive 68pdr. mounted topside. Entering service with high expectations, she attracted much attention as the first purpose-built screw line-of-battle ship in the Royal Navy and was sent straight to the Black Sea where the Crimean War with Russia was just beginning. Serving as Second Flagship to the fleet there, she saw a great deal of action and came home with several battle honours to her credit.
The measure of her success was then confirmed when, in 1856, she was chosen as the vessel most suitable to lay the first Atlantic Telegraph cable and underwent conversion as necessary. After loading the 1,250 tons of cable at Greenwich in 1857, the first attempt that summer proved a costly failure when the cable broke after 355 miles had been laid. A second attempt the next year was more successful however and, on 29th July 1858, the two ends were spliced together when Agamemnon met her American counterpart, the U.S.S. Niagara, in mid-Atlantic. Once both vessels had returned to their respective continents with news of the triumph, Queen Victoria sent an inaugural message to President Buchanan on 16th August amidst huge national excitement even though, in the event, the cable failed after only three weeks. Nothing could detract from Agamemnon's role in the great enterprise however and, when she was finally broken up in 1870, it was this for which she was largely remembered.