Illustration from Ming Chinese ophthalmology text, Ms copy

Illustration of Deep-rooted nail-like nebula (ding yi gen shen), an 'external eye disease' (waizhang), from Michuan yanke 72 zheng quanshu (Secretly Transmitted Compendium of 72 Ophthalmic Diseases) by Yuan Xueyuan (Ming period, 1368-1644). This book uses a combination of text and pictures to explain the symptoms, causes and treatment of 72 different eye conditions, 48 of which are described as external.

Picture heading: Deep-rooted nail-like nebula (ding yi gen shen), external eye disease (waizhang)