Established by the mid-seventeenth century as the most powerful type of sailing battleship, the ship of the line remained supreme until the coming of steam and armor plate in the late 1850s. Ships of the line were heavy warships considered, by the number of their guns, strong enough to join the line of battle: the fighting fleet formation in which the biggest number of heavy guns could be brought to bear on the ships of the enemy fleet.
By the middle eighteenth century, ships of the line were rated by their gun totals. A three-decked First Rate carried 100 guns or more, The biggest ever built was Spain’s Santissima Trinidad of 136 guns, sunk after Trafalgar in 1805. Then came second Rates (84-100 guns), Third Rates (70-84 guns) and Fourth Rates (50-70 guns). By the French wars of 1792-1815 , the standard ship of the line was the two-decked Third Rate of 74 gun, with a crew of about 450 men. In battle, a ship of the line’s rate of fire and crew’s fighting spirit were always more important than ship size or number of guns. At Cape St. Vincent (February 14, 1797), Nelson’s 74-gun Captain, though badly damaged, took both the Spanish San Nicolas and San Josefby running alongside and boarding.
To prevent the weight of the upper gun decks from making the ship top-heavy, the ship was built with a sharp “tumble-home”, or inward sloping of the sides. In Victory the heaviest guns were carried on the lower gun deck (32-pounders), with 24-pounders on the middle gun deck and 12-pounders on the upper gun deck.
It was rare for wooden battleships to sink each other in battle. They tried to batter enemy ships into wrecks for capture by boarding. Apart from solid roundshot, the guns could fire whirling “disabling shot” for slicing enemy rigging, and “grapeshot” for cutting down large numbers of men.