Six-Harmonies Cannons

Records of Military Armament, Volume 122

Military Equipment: Fire

Illustrated Explanations of Firearms

Page 8

The Six-Harmonies CannonOriginal: Liuhe Pao (六合砲). The term "Six-Harmonies" refers to the six cardinal directions—North, South, East, West, Above, and Below—symbolizing the entire universe or a perfect, unified whole. In engineering, it refers to the six longitudinal segments used to form the barrel. is a specialized firearmOriginal: huoqi (火器). constructed through a composite assembly method.

To create the cannonOriginal: pao (砲)., one must prepare six individual longitudinal staves of either hardwood or iron. These segments are shaped so that, when placed together, they form a perfect hollow cylinder for the bore. This core assembly is then reinforced with a series of external iron hoops, driven tightly around the circumference to bind the "six harmonies" into a single, high-pressure chamber.

This construction method allows for the production of large-bore artillery in environments where large-scale metal casting is difficult or impossible. By utilizing smaller, prefabricated segments that are "harmonized" into one body, a formidable weapon can be assembled quickly for field use.

The diagram shows the side profile of the barrel and the cross-sections of the six segments.

As with other defensive weapons of this era, the interior is loaded with a powerful charge of gunpowder. Because of its reinforced, hooped construction, it is more durable than the simple wooden cannon and can potentially be reused if the hoops are sufficiently strong, though it remains a bridge between improvised siege gear and permanent heavy artillery.