Feng Lei Huo Gun (風雷火滾)

Three Feng Lei Huo Gun, from 'Wu Bei Zhi (《武備志》)'.

Feng Lei Huo Gun (風雷火滾, lit. 'Wind and thunder fire roller') is a rolling cylindrical explosive device similar to Ping Kuang Bu Zhan Sui Di Gun (平曠步戰隨地滾) as well as Shuang Fei Huo Long Jian (雙飛火籠箭). Feng Lei Huo Gun is made of bamboo basketry, wrapped in forty to fifty layers of paper and filled with poison smoke gunpowder and five bomblets. Unlike its wooden counterpart, Feng Lei Huo Gun is not equipped with rocket propeller. It is presumably thrown directly by hand, or rolled down from a slope.