the dogger was a development of the ketch. it was gaff-rigged on the main-mast, and carried a lug sail on the mizzen, with two jibs on a long bowsprit. the boats were generally short, wide-beamed and small, and carried out trawling or line fishing on the dogger bank. the name dogger was practically synonymous with ketch from the early seventeenth century, until the ketch began to increase in size during the period, eventually rising above 50 tons in the middle of the century.