I thought he would mention just how that much powder was touched off. A man standing at the breech, pulled a lanyard. Flint lock, percussion cap igniting another small powder charge???? Good thing Malta is a windy island the smoke cloud must have been impressive.
The ship I served on, USS Ingraham DD694, in the early sixties pulled in there for liberty. As a young sailor I was more interested in the sights of Valletta then I was a British fort. Malta was very much UK then.
I seem to recall that large 16 inch/50 Naval ship guns had a small blackpowder charge that set of the main charge, could be mistaken I wasn't a Gunners Mate.