Thanks to everyone who has responded with information to help me understand 'nautical' tons. In essence what I now know is that Queen of the Bay's registered tonnage was 391 tons, based on a complicated calculation which I am only just beginning to understand, while her cargo carrying capability was 800 tons. Best wishes Rosemary Rodliffe Our resources available on-line: <http://www.thornburypump.co.uk/Ancestry/resources.php> http://www.thornburypump.co.uk/Ancestry/resources.php Kelly's Directories of Norfolk and Cambridgeshire 1900 Return of Owners of Land in Norfolk 1873 Newnes Round the Coast 1895 Black's Guides to Cornwall 1879, Gloucestershire 1875 and South Wales 1883 Norfolk photographers details free at <http://www.earlyphotographers.org.uk/> http://www.earlyphotographers.org.uk/