Hello again, Pentire,
Taking a closer look with fresher eyes, (it was the wee smalls here in Canada when I replied last night), I'm thinking that it was a London-registered vessel he was on at the time of his death, "64" being the Port Number for London.
Unfortunately for your research, your man's death happened just a little over a year before the Board of Trade (abbreviated as either BoT or BT) stopped using that arcane code of Port Numbers and Vessel Rotation Numbers and started writing in the name of the vessel in plain English as you will notice looking at the other masters on that page.
Did your man have siblings who were also mariners? I notice
- Arthur DAY b. Appledore 1810, certificate #38,035
- Robert DAY b. Appledore 1812, certificate #38,357
- William DAY b. Appledore 1822, Register Ticket #79951, Mate Certificates #58311 and #68,027
Cheers,
Westoe