From these and other circumstances it is indubitable that gunpowder was used by the Chinese as an explosive compound in prehistoric times; when they first discovered or applied its power as a propellant is less easily determined. Stone mortars, throwing missiles of 12 lbs. to a distance of 800 paces, are mentioned as having been employed in 767 A.D. by Thang's army; and in 1282 A.D. it is incontestable that the Chinese besieged in Cai'fong-fou used cannon against their Mongol enemies. Thus the Chinese must be allowed to have established their claim to an early practical knowledge of gunpowder and its effects. ↑ Original from Harvard University John Clark Ridpath, ed.