[Archive] Counterweight whirlwind trebuchet? (Patreon)

Note: This short article is taken from a deleted portion of my blog post about Xuan Feng Pao (旋風砲) as I find it too speculative and possibly erroneous for my liking. It is only kept here for archival purpose.

Although not explicitly specified, some editions of Wu Jing Zong Yao (《武經總要》) contain illustrations that depict what appears to be counterweight version of Xuan Feng Pao mounted on warship (see picture). This suggests that Chinese people may have developed a type of fixed counterweight trebuchet as early as 11th century, well before Mongol invaders introduced them to the more advanced swinging counterweight trebuchet during the 13th century.