The ancient literature records about the shape and function of the "Nine Needles" are basically the same as those in the "Ling Shu" (a Chinese medical text). However, the "Nine Needle Diagram" attached to different documents in different periods reflects to some extent the evolution of acupuncture needles in different historical periods.
Nine Needle Diagram from the "Zhen Jing Zhai Ying Ji" by Du Sijing in the Yuan Dynasty
Nine Needle Diagram from the "Zhen Jiu Da Cheng" by Yang Jizhou in the Ming Dynasty
Nine Needle Diagram from the "Yi Zong Jin Jian" by Wu Qian in the Qing Dynasty
