Wan-li: Year 19, Month 1, Day 26
19 Feb 1591
The former Assistant Censor-in-Chief Huang Ying-jia memorialized, noting: "In defending against the yi, much use is made of firearms (火器). Of these firearms, the Senior General Cannon (大將軍砲) is the most deadly. However, it weighs several hundred jin and it is difficult to use. The Fo-lang-ji are efficacious, but can only kill one horseman, and they are very expensive to manufacture..."
Zhong-yang Yan-jiu yuan Ming Shi-lu, volume 106, page 4285/86