31ft LOA is a small smack; she might be 26ft LWL. Say 9ft beam, and 4ft 6ins draft? Full bodied form, so my guess is in the region of 8 or 9 tons, of fully ballasted, which many are not! Boadicea is decidedly heavier than that, but she is an antique, with a Georgian shape, compared to the Victorian yacht influenced shape of later smacks,