Collation of the Disordered Text on the“Outward Curve”and“Inward Curve”in the“Bowyer”Section of the Kaogong Ji

The Bowyer section of the Kaogong ji may be the earliest document of on bow making in the world. The technical term the outward curve wang ti refers to the reflex when unstrung and the inward curve lai ti the deflex when strung. According to Shen Kuo􀆳s Mengxi bitan a bow with less reflex is less powerful than a bow of the same design but with more reflex. Based on evidence from both the method to make a circle and wood ̄cutting guide of the Kaogong ji itself the six bow order of Zhouli the Mengxi bitan and modern archery the author has proved that a traditional composite bow with more reflex and less deflex is more powerful than a bow of the same design but with less reflex and more deflex. Certain commentaries on the Bowyer section have been wrong for almost two thousand years because of disorder in the extant text. The collated text reads Bows of the king􀆳s class are curved when unstrung and slightly curved when strung. These are advantageously used in shooting at shields armors and wood marks. Bows of the hunting and fowling classes are slightly curved when unstrung and curved when strung. They are used in shooting at archery targets or flying birds. Bows of the Tang class are equally curved whether strung or un ̄ strung. They are used with advantage in shooting deep into an object.