I may be wrong, but I understood that the bombard had belonged to James II but it was damaged when firing a salute for the Duke of Albany who was to become James VII and II. Since the cannoneer was English, foul play was suggested because the English had nothing as big. It was regarded as a bad omen for the future king, his reign certainly did not end well for him as he was deposed in the Glorious Revolution.The canon is now at Edinburgh Castle its called' Mons Meg' minus a chunk that blew off and hit the king .It was a breach loader cant trust them breech loaders ! To be fair I expect they loaded from the muzzle but its made with two sections ,I think its 21" bore & smaller than the Dardanelles gun. That's at the Tower of London again a breach loader if perhaps just to transport it . Both fired stone balls .Don't try That at home !.
Re James 11probally much like Wm the third Iv'e made them . No idea what TRS offer now my last catalogue is1999 edition . All interesting
Regards Rudyard