In the rating system of the Royal Navy used to categorise sailing warships, a first rate was the designation for the largest ships of the line. Originating in the Jacobean era with the designation of Ships Royal capable of carrying at least 400 men, the size and establishment of first-rates evolved over the following 250 years to eventually denote ships of the line carrying at least 80 guns across three gundecks. By the end of the eighteenth century, a first-rate carried no fewer than 100 guns and more than 850 crew, and had a measurement (burthen) tonnage of some 2,000 tons.
In 1603 all English warships with a complement of fewer than 160 men were known as 'small ships'. In 1625/26 to establish pay rates for officers, a six-tier naval ship rating system was introduced. These small ships were divided into three tiers: fourth-, fifth- and sixth-rates. Up to the end of the 17th century, the number of guns and the complement size were adjusted until the rating system was actually clarified. A 'fourth-rate' was nominally a ship of over thirty guns with a complement of 140 men.
In the 18th century and most of the 19th, a sloop-of-war in the Royal Navy was a warship with a single gun deck that carried up to eighteen guns. The rating system covered all vessels with 20 guns and above; thus, the term sloop-of-war encompassed all the unrated combat vessels, including the very small gun-brigs and cutters. In technical terms, even the more specialised bomb vessels and fireships were classed as sloops-of-war, and in practice these were employed in the sloop role when not carrying out their specialised functions.
In the rating system of the Royal Navy used to categorise sailing warships, a second-rate was a ship of the line which by the start of the 18th century mounted 90 to 98 guns on three gun decks; earlier 17th-century second rates had fewer guns and were originally two-deckers or had only partially armed third gun decks. A "second rate" was the second largest class of warships in a hierarchical system of six "ratings" based on size and firepower.
In the rating system of the Royal Navy used to categorise sailing warships, a fifth rate was the second-smallest class of warships in a hierarchical system of six "ratings" based on size and firepower.
The rating system of the Royal Navy and its predecessors was used by the Royal Navy between the beginning of the 17th century and the middle of the 19th century to categorise sailing warships, initially classing them according to their assigned complement of men, and later according to the number of their carriage-mounted guns. The rating system of the Royal Navy formally came to an end in the late 19th century by declaration of the Admiralty. The main cause behind this declaration focused on new types of gun, the introduction of steam propulsion and the use of iron and steel armour which made rating ships by the number of guns obsolete.
HMS Cornwall was a 74-gun third-rate Vengeur-class ship of the line built for the Royal Navy in the 1810s. She spent most of her service in reserve and was converted into a reformatory and a school ship in her later years. The ship was broken up in 1875.
HMS St Lawrence was a 102-gun first-rate wooden warship of the Royal Navy that served on Lake Ontario during the War of 1812. Built on the lake at the Royal Navy dockyard in Kingston, Ontario, she was the only Royal Navy ship of the line ever to be launched and operated entirely in fresh water. Constructed in 1814, the ship's arrival on the lake ended all naval action and St Lawrence finished the war having never gone into battle. Following the war, the vessel was laid up, eventually being sold in 1832 to private interests. The ship later sank and is now a recreational dive spot.
HMS Unicorn was a 28-gun Lyme-class sixth-rate frigate of the Royal Navy. She was originally ordered as a 24-gun ship to the draft of the French privateer Tyger. The third vessel of the Royal Navy to bear the name, Unicorn, as well as HMS Lyme which was a near-sister, were the first true frigates built for the Royal Navy. They were actually completed with 28 guns including the four smaller weapons on the quarterdeck, but the latter were not included in the ship's official establishment until 22 September 1756. The two ships differed in detail, Unicorn having a beakhead bow, a unicorn figurehead, two-light quarter galleries, and only five pairs of quarterdeck gunports, while Lyme had a round bow, a lion figurehead, three-light quarter galleries, and six pairs of quarterdeck gunports.
HMS Gloucester was a 74-gun, third rate Vengeur-class ship of the line built for the Royal Navy in the 1810s. She played a minor role in the Napoleonic Wars and was cut down into a 50-gun fourth rate frigate in 1831–32. The ship was converted into a receiving ship and broken up in 1884.
HMS Valorous was one of two 16-gun, steam-powered Magicienne-class second-class paddle frigates built for the Royal Navy in the 1850s. Commissioned in 1853 she played a small role in the Crimean War of 1854–1855 and was sold for scrap in 1891.
HMS Superb was a 80-gun second rate Vanguard-class ship of the line built for the Royal Navy in the 1840s. She was broken up in 1869.
HMS Falmouth was a 50-gun fourth-rate ship of the line built for the Royal Navy in the first decade of the 18th century. The ship participated in several battles during the War of the Spanish Succession (1701–15) and the War of Jenkins' Ear (1739–48).
HMS Milan was a 38-gun fifth rate frigate of the Royal Navy. She had previously been Ville de Milan, a 40-gun frigate of the French Navy, but served for only a year before being chased down and engaged by the smaller 32-gun frigate HMS Cleopatra. Ville de Milan defeated and captured her opponent, but suffered so much damage that she was forced to surrender without a fight several days later when both ships encountered HMS Leander, a British fourth rate. Milan went on to serve with the Royal Navy for another ten years, before being broken up in 1815, after the conclusion of the Napoleonic Wars.
Post ship was a designation used in the Royal Navy during the second half of the 18th century and the Napoleonic Wars to describe a sixth-rate ship that was smaller than a frigate, but by virtue of being a rated ship, had to have as its captain a post captain rather than a lieutenant or commander. Thus ships with 20 to 26 guns were post ships, though this situation changed after 1817.
HMS Janus was a 44-gun Roebuck-class fifth rate of the Royal Navy.
HMS Ariadne was a 20-gun Hermes-class sixth-rate post ship built for the Royal Navy during the 1810s. The vessel was completed in 1816, modified in the early 1820s and only entered service in 1823. Ariadne was assigned to the Cape of Good Hope Station, followed by a stint in the Mediterranean Sea. The ship served on the North America and West Indies Station from 1829 to 1835. She was paid off in 1835, turned into a coal hulk the following year and sold for scrap in 1841.
HMS Thetis was a 46-gun Leda-class fifth-rate frigate built for the Royal Navy during the 1810s. She was first commissioned in 1823 and was assigned to the South America Station three years later. The ship was wrecked in 1830 off Cape Frio, Brazil, with the loss of 22 crewmen; most of her cargo of bullion was successfully salvaged.
HMS Arethusa was a 46-gun Leda-class fifth-rate frigate built for the Royal Navy during the 1810s. The ship was never commissioned and was converted into a lazarette in 1836. She was renamed HMS Bacchus in 1844 and was further converted into a coal hulk in 1851–52. The ship was sold for scrap in 1883.
HMS Talbot was a 28-gun Atholl-class sixth-rate frigate built for the Royal Navy during the 1820s.
