[1] The distinctive san yan chong, or three eyed gun, was one of the most common Ming hand cannons.
Functionally they were no different from many contemporary European hand cannons—a solid metallic head with an aperture behind it for different tail fittings to be attached, ranging from the butt of a staff, a spearhead, to a specialized short curved stock with a raised sight that enabled the gunner to fire it while kneeling—these would be called "Divine Machines."
Historians have attributed their design to be refined from primitive fire lances—which consisted of bundles of single joint of bamboos tied around a spear.
As time progressed though, metal barrels appeared during the 12th century, and could not only shoot out spouts of flames like a small flame thrower but they could also fire porcelain shards or metal scraps as shrapnel.
As the Ming dynasty neared its collapse, the production and deployment of these multi-barrelled guns actually rose drastically against the rising Manchu threat.