« Reply #8 on: Monday 30 March 20 18:33 BST (UK) »
There might be a glimmer of hope of finding a record and that is if he had been impressed into the navy during a period when Britain was gearing up for one of its endless wars, e.g. at the end of the 1700s bad blood with Denmark meant there was a call to enlarge our navy.
Surfing will find a few articles on imppressmen but there's an outline on this webpage
https://en.wikipedia.org/wiki/ImpressmentThere are definitely some records of the in-patients and offspring of Queen Anne's seafarers Greenwich hospital, London. There are supposed to be some records of outpatients too but I've been unable to locate the Edinburgh ones, which should have details of my ancester.
https://en.wikipedia.org/wiki/Greenwich_Hospital,_London
Aberdeen: Findlay-Shirras,McCarthy: MidLothian: Mason,Telford,Darling,Cruikshanks,Bennett,Sime, Bell: Lanarks:Crum, Brown, MacKenzie,Cameron, Glen, Millar; Ross: Urray:Mackenzie: Moray: Findlay; Marshall/Marischell: Perthshire: Brown Ferguson: Wales: McCarthy, Thomas: England: Almond, Askin, Dodson, Well(es). Harrison, Maw, McCarthy, Munford, Pye, Shearing, Smith, Smythe, Speight, Strike, Wallis/Wallace, Ward, Wells;Germany: Flamme,Ehlers, Bielstein, Germer, Mohlm, Reupke