Hi Jim,
Thanks as always for your detective work. The timescale, and the initials of course, tie in very well with the typology of the sword. I found another sword attributed to Thomas Cullum with the marks also stamped on the flat of the guard albeit the underside as opposed to mine which is on the topside.
https://bid.candtauctions.co.uk/lot-...F10%3Fpage%3D2 Another one at the National Maritime Museum
https://www.rmg.co.uk/collections/ob...c-object-78453 A mystery solved I hope.
My Regards,
Norman.
P.S. The U.K. National Archives have a catalogue description of the will of a Thomas Cullum, Sword Cutler of St Martin in the Fields, Middlesex.