I'm sure most of you have heard this term before, usually referencing a large revolver of .44 caliber or bigger, or maybe a Desert Eagle. Those guns are for little girls or Jimmy Carter or something.
THIS is a hand cannon. I don't really have any information on this gun. Longtime readers will note that my research only lasts for a few short seconds and is lets say "shallow". I think it may be of French origin or from the French-speaking world, but that is only because the pic was titled "Canon Main" but it certainly could be it was just from a French person. It looks to be from the 1700's or earlier and it appears it was cast in one piece, although I am not sure about the metal.
Rather than a direct fire, large bore gun, it also could be a type of small mortar or grenade launcher since the bore is so wide. Another theory I came up with is that it is a flare gun or some other type of signaling device, due to the shooting star engraved on the barrel.
Whatever it is, I though it was cool and though you might think so too. If anyone out there has any more info or even guesses, let me know.