of writings attributed to Geber which have been examined are in Latin, but the library of Leyden is said to possess some works by him written in Arabic.

These MSS.

contain directions for preparing many metals, salts, acids, oils, etc., and for performing such operations as distillation, cupellation, dissolution, calcination, and the like.
Of the other Arabian alchemists, the most celebrated in the middle ages were _Rhasis_, _Alfarabi_, and _Avicenna_, who are supposed to have lived in the 9th and 10th centuries.
The following story of Alfarabi's powers is taken from Waite's _Lives of the Alchemystical Philosophers_:-- "Alfarabi was returning from a pilgrimage to Mecca, when, passing through Syria, he stopped at the Court of the Sultan, and entered his presence, while he was surrounded by numerous sage persons, who were discoursing with the monarch on the sciences.

Alfarabi ...

presented himself in his travelling attire, and when the Sultan desired he should be seated, with astonishing philosophical freedom he planted himself at the end of the royal sofa.