 The concept of small sailing frigates with a complementary set of oars ( or " sweeps " ) was not new . The English Tudor navy had used small " galleasses " in the mid @-@ 16th century . In the 1660s its successor , the Royal Navy , equipped the equivalent of sixth @-@ rates with oar ports on or below the gundeck . During the 18th century the Russian Navy introduced " shebecks " , Baltic variants on the Mediterranean xebecs , for inshore duties . The xebecs were good sailers , could be rowed if necessary and had more guns and greater stores than galleys ; they were also less expensive to maintain . The Russian designs influenced Chapman and the Swedish naval commanders . Consequently , Chapman 's designs for new ships were elaborations on those principles , but with adaptations to archipelago warfare . 
