The "seventy-four" was a type of two-decked sailing ship of the line which nominally carried 74 guns. It was developed by the French navy in the 1740s and spread to the British Royal Navy where it was classed as third rate. From here, it spread to the Spanish, Dutch, Danish and Russian navies. The design was considered a good balance between firepower and sailing qualities, but more importantly, it was an appealing ideal for naval administrators and bureaucrats. Seventy-fours became a mainstay of the world's fleets into the early 19th century. From the 1820s, they began to be supplanted by larger two-decked ships mounting more guns, and ultimately in the later 19th century by ironclads.