[Surgery attributable to Abu l-Qasim in Wolfram von Eschenbach's 'Parzifal']

None of the medieval chivalresque romances deals with topics from natural science to such an extent as the Parzival of Wolfram von Eschenbach. In the Urjans-episode this highly learned German poet describes a thoracocentesis by means of a wooden tube, which evacuates accumulated blood out of the wounded knight's chest. Due to the relief of the blood's pressure on his heart the normal circulation of his blood is restored and Urjans awakes from unconsciousness. Up to now this outstanding description of a not everyday surgical therapy could not be traced back into the history of medicine. There is, however, a striking parallel in the Chirurgia (chapter 100) of Abu l-Qasim Halaf Ibn al-'Abbas az-Zahrawi, which reads, even in details, like Wolfram's text except the fact that Wolfram takes a tube for evacuating the blood whereas Abu l-Qasim suggests a cord made of cotton. Wolfram must have had a professional knowledge of surgery, yet we do not know in which way he became acquainted with Gerard's of Cremona latin translation of his arabic source.