This is from Usama ibn Munqidh's autobiography
Yes, but this is also from his autobiography, something far less quoted but equally important;
I have, however, witnessed a case of their medicine which was quite different from that.
"...a horse kicked him in the leg, which was subsequently infected and which opened in fourteen different places.
Every time one of these cuts would close in one place, another would open in ancther place. All this happened while I was praying for his perdition.
Then came to him a Frankish physician and removed from the leg all the ointments which were on it and began to wash it with very strange vinegar. By this treatment all the cuts were healed and the man became well again. He was up again like a devil.
Another case illustrating their curious medicine is the following: In Shayzar we had an artisan named abu-al-Fath, who had a boy whose neck was afflicted with scrofula.
Every time a part of it would close, another part would open. This man happened to go to Antioch on business of his, accompanied by his son.
A Frank noticed the boy and asked his father about him.
Abu-al-Fath replied, "This is my son." The Frank said to him, 'Wilt thou swear by thy religion that if I prescribe to you a medicine which will cure thy boy, thou wilt charge nobody fees for prescribing it thyself?
In that case, I shall prescribe to you a medicine which will cure the boy."
The man took the oath and the Frank said:
Take uncrushed leaves of glasswort, burn them, then soak the ashes in olive oil and sharp vinegar. Treat the scrofula with them until the spot on which it is growing is eaten up.
Then take burnt lead, soak it in ghee butter and treat him with it. That will cure him.
The father treated the boy accordingly, and the boy was cured. The sores closed and the boy returned to his normal condition of health.
I have myself treated with this medicine many who were afflicted with such disease, and the treatment was successful