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Navy constructed the four-deck, 136-gun Pennsylvania and the French Navy, the 120-gun Valmy, (both with similar flush deck arrangement). Santísima Trinidad remains notable as one of the few four-decker ships of the line ever built. It was even suggested by some naval officers that she should be restricted to defending the Bay of Cádiz. The weight of the additional guns, so high above her waterline, made her poor sailing qualities even worse, leading to her nickname, El Ponderoso.
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Her armament seems to have been quickly reduced to 130 from 136 guns, but she still carried more guns than any other ship of her time. In 1795, her forecastle was joined to her quarterdeck to create a fourth deck containing a battery of eight pounder guns, giving her a total of 130 guns. She was reputed to be the largest warship in the world, for which she was nicknamed El Escorial de los mares by the Spanish, until surpassed in sheer size by the new type French 120-gun ships such as Océan (1790) and Orient (1791). There is no complete plan of the ship in existence, but there are of the 112-gun ship from 1765, from which the original dimensions of the ship may be found. She was considerably larger than her British contemporary Victory and somewhat bigger than the French Bretagne. and the ship was launched in March 1769 and completed in August 1769 as a 116-gun three-decker. He died on 25 November 1767, and the construction of the ship was continued by his son, Ignacio Mullán. She was built at Havana, Cuba, to a design by Irish naval architect Matthew Mullan (domiciled in Spain under the name Mateo Mullán), originally intended as a ship of 112 guns. She was the heaviest-armed ship in the world when rebuilt, and bore the most guns of any ship of the line outfitted in the Age of Sail.
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This was increased in 1795–96 to 130 guns by closing in the spar deck between the quarterdeck and forecastle, and to 136 guns around 1802 (plus 4 small guns on the poop), thus creating what was in effect a continuous fourth gundeck although the extra guns added were actually relatively small.
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Nuestra Señora de la Santísima Trinidad, nicknamed La Real, sometimes confused with the galleon Santísima Trinidad y Nuestra Señora del Buen Fin) was a Spanish first-rate ship of the line with 112 guns.
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