Looking Like A Christian, Sir

In Nelson's day, most crewmen were remakably talented seamsters, not only applying needle and thread to repairing damaged sails, but also repairing - and often making - their own uniforms. Back then, the Navy never supplied uniforms to deck hands, while officers had their uniforms tailor made. So it was in the classic maritime tradition that I set to work adorning my Jack Aubrey costume with appropriate finery.

Now, how do I go about gaining thirty kilos for supreme veritas?