Why some 'stone frigates' carry sloop names

Twenty-four ships formed much of the Royal Navy's existing sloop force in the 1920s and 1930s, giving the group its plain 24 Class label. Their names included Flying Fox, Eaglet, and President, all later associated with Royal Naval Reserve shore establishments. Those establishments are conventionally called stone frigates, yet the names in these examples came from sloops. The aside shows how naval institutions can preserve the memory of a ship type after the original hulls disappear.