The Royal Navy used fourth rates on North American, Indian Ocean, and other remote stations where they could carry a commodore or admiral and lead frigate squadrons. The East India Company dockyard at Bombay, later taken over by the Royal Navy, produced strongly built teak East Indiamen that could be converted into roughly 56-gun two-deckers. They offered command space and looked substantial enough at a distance to be mistaken for a third rate. A fourth rate could therefore provide useful firepower and presence without subtracting a more valuable line-of-battle ship from European or Mediterranean operations. Even here it competed with small 64-gun third rates, which could perform the same flagship role with greater fighting power.
Chapter · 17:14-19:56
Why fourth rates suited distant stations
On distant stations, fourth rates offered an imposing two-deck flagship and useful firepower without pulling a major line-of-battle ship from home waters.