This manuscript from the Book of Tazkirat Al-Kahaleen was by Ali Al-Kahaal who died in AH 430 (AD 1309).
The manuscript was written with black ink, and some words are written in red ink.
It specialized in ophthalmology. The manuscript is divided into three reports talking about the eye, its anatomy, its obvious and hidden diseases, the reason for them, and how to cure them.
In the 53rd chapter, it talks about cancer of the cornea, precisely diagnosing it and showing its symptoms as headache and loss of appetite. It explains that sharp kohl hurts the cornea patient's eyes and that such disease is incurable, explaining that there is no medicine stronger than such a disease.
According to the theory mentioned in this book, a medicine should be stronger than the disease.