 While smaller than a ship-of-the-line, they were formidable opponents for the large numbers of sloops and gunboats, not to mention privateers or merchantmen.Able to carry six months' stores, they had very long range; and vessels larger than frigates were considered too valuable to operate independently.Frigates scouted for the fleet, went on commerce-raiding missions and patrols, and conveyed messages and dignitaries.