The accounts which have come to us of the men who followed the pursuit of the One Thing are vague, scrappy, and confusing.
Alchemical books abound in quotations from the writings of Geber. Five hundred treatises were attributed to this man during the middle ages, yet we have no certain knowledge of his name, or of the time or place of his birth. Hoefer says he probably lived in the middle of the 8th century, was a native of Mesopotamia, and was named Djabar Al-Konfi. Waite calls him Abou Moussah Djafar al-Sofi. Some of the mediaeval adepts spoke of him as the King of India, others called him a Prince of Persia. Most of the Arabian writers on alchemy and medicine, after the 9th century, refer to Geber as their master.
All the MSS. 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. The
Prince, aghast at his boldness, called one of his officers, and in
a tongue generally unknown commanded him to eject the intruder.
The philosopher, however, promptly made answer in the same tongue:
'Oh, Lord, he who acts hastily is liable to hasty repentance.' The
Prince was equally astounded to find himself understood by the
stranger as by the manner in which the reply was given. Anxious to
know more of his guest he began to question him, and soon
discovered that he was acquainted with seventy languages. Problems
for discussion were then propounded to the philosophers, who had
witnessed the discourteous intrusion with considerable indignation
and disgust, but Alfarabi disputed with so much eloquence and
vivacity that he reduced all the doctors to silence, and they
began writing down his discourse. The Sultan then ordered his
musicians to perform for the diversion of the company. When they
struck up, the philosopher accompanied them on a lute with such
infinite grace and tenderness that he elicited the unmeasured
admiration of the whole distinguished assembly. At the request of
the Sultan he produced a piece of his own composing, sang it, and
accompanied it with great force and spirit to the delight of all
his hearers. The air was so sprightly that even the gravest
philosopher could not resist dancing, but by another tune he as
easily melted them to tears, and then by a soft unobtrusive melody
he lulled the whole company to sleep."