A ship’s ‘rate’ was basically decided by the number of guns she carried, from the largest 120-gun First Rate, down to the Sixth Rate 20-gun ships. The smaller ‘unrated’ vessels (sloops, brigs, bomb vessels, etc) were commanded by more junior officers (Commanders, Lieutenants) but a ‘rated’ ship was always a Captain’s command and always ship rigged; that is with three square rigged masts.

First Rate

The biggest ships of the fleet with their gun batteries carried on three decks, were generally used as flagships and fought in the centre of the line-of-battle. They were armed with a minimum of 100 heavy cannon, carried a crew of about 850 and were over 2000 tons Builder’s Measure (a formula for calculating the capacity of the ship, not the displacement of the ship as is the practice nowadays).

Second Rate

The Second Rate ships of the line were also three-deckers, but smaller and thus cheaper versions of the First Rates. They mounted between 90 and 98 guns, and like the First Rates fought in the centre of the line-of-battle. Generally around the 2000 ton mark, they had a crew of approximately 750. Like the First Rates, they had 32 pounder guns on the gundeck, but 18 pounders instead of 24 pounders on the middle deck, with 12 pounders on the upper deck (compared to 18 or 24 pounders on First Rates). Both First and Second Rates carried lighter guns or carronades on their forecastles and quarterdecks. Unlike the First Rates, which were too valuable to risk in distant stations, the Second Rates often served overseas as flagships. They had a reputation for poor handling and slow sailing.

Third Rate

The most numerous line-of-battle ships were the two-decker Third Rates with between 64 and 80 guns. The most effective and numerous of these was the 74-gun ship, in many ways the ideal compromise of economy, fighting power and sailing performance, which formed the core of the battlefleet. They carried 32 pounder guns on the gundeck and 18 pounders on the upperdeck, with a crew of 600 to 650 men.

Fourth Rate

Two decker ships of 50 to 60 guns were by the end of the 18th century, no longer reckoned to be ‘fit to stand in the line of battle’. Despite this, 50 gun ships were heavily engaged in the line at the battles of Camperdown and Copenhagen. With two decks, their extra accomodation made them suitable flagships for minor overseas stations, while their relatively shallow draught made them suitable as headquarter ships for anti-invasion operations in the North Sea and the English Channel. They were also useful as convoy escorts, troopships and even on occasion, as convict transports. In normal service they had a main armament of 18 pounders, a crew of 350 and measured around 1000 tons.

Fifth Rate

These were the frigates, the Navy’s ‘glamour ships’. With their main armament on a single gundeck, they were the fast scouts of the battlefleet, when not operating in an independent cruising role, searching out enemy merchant ships, privateers or enemy fleets. Developed from early-18th century prototypes, the Fifth Rates of Nelson’s time had a variety of armaments and gun arrangements, from 32-gun ships armed with 12 pounders to 36 and 38-gun frigates with 18 pounders, even some 40-gun ships and cut down two-deckers with 24 pounders. Captured enemy frigates were also used in service, and many of the best British-built ships were copied or adapted from French designs. All classes carried lighter guns and carronades on the quarterdeck and forecastle. Their tonnage ranged from 700 to 1450 tons, with crews of 250 to 300 men.

Sixth Rate

The Sixth Rates were smaller and more lightly armed frigates, with between 22 and 28 nine-pounder guns, a crew of about 150, and measured 450 to 550 tons. There were never enough frigates: while Lord Nelson was searching for the French fleet before the battle of the Nile he said, ‘Frigates! Were I to die this moment, want of frigates would be found engraved on my heart!’

Unrated vessels included the following:

Sloop

A sloop of war was a vessel commanded by an officer with the rank of Commander. Sloops could be armed with between 10 and 18 guns, be ship rigged or brigs (two-masted square rig) and were capable of most of the tasks undertaken by frigates, with the exception of fleet reconnaisance. They were often armed with carronades, giving them a heavy punch at close range. The cruiser class was the most numerous class of sailing warships ever built, over 100 of these 380 ton, 18 gun brig sloops being built. They carried a crew of 120 men.

Bomb vessels and fireships

Developed from two-masted craft (ketches) armed with mortars for shore bombardment, and first used by the French in the late 17th century, the bomb vessel of the late 18th century had ship rig. These strongly built ships were sometimes used for naval expeditions to the Arctic: the young midshipman Nelson made one such voyage in the Carcass. The fireship, intended as a means of setting an enemy ship on fire, was often a converted merchantship, though some were specially built for the Royal Navy. Both the bomb vessel and the fireship were only seldom used in their designed role, but proved useful as patrol or convoy escort sloops.

Gunboats and gunbrigs

These were small, two-masted vessels, a Lieutenant’s command, and originally intended for anti-invasion patrol. Later, they developed into more capable vessels fit for a variety of tasks. They were built to a wide variety of classes, and often had evocative names, for instance Grappler, Growler and Griper were three ‘Courser’ Class gunbrigs.

Cutters

Developed from craft used by English smugglers, these single masted vessels were built for speed. They were employed as patrol boats and despatch carriers. Schooners, two masted fore- and aft-rigged vessels developed from American types were similarly used.