nd the commencement of his _Canon of Medicine_
also dates from his stay in Hyrcania.

He subsequently settled at Rai, in the vicinity of the modern Teheran,
where a son of the last amir, Majd Addaula, was nominal ruler, under the
regency of his mother. At Rai about thirty of his shorter works are said to
have been composed. But the constant feuds which raged between the regent
and her second son, Shams Addaula, compelled the scholar to quit the place,
and after a brief sojourn at Kazw[=i]n, he passed southwards to Hamad[=a]n,
where that prince had established himself. At first he entered into the
service of a high-born lady; but ere long the amir, hearing of his arrival,
called him in as medical attendant, and sent him back with presents to his
dwelling. Avicenna was even raised to the office of vizier; but the
turbulent soldiery, composed of Kurds and Turks, mutinied against their
nominal sovereign, and demanded that the new vizier should be put to death.
Shams Addaula consented that he should be banished from the country.
Avicenna, however, remained hidden for forty days in a sheik's house, till
a fresh attack of illness induced the amir to restore him to his post. Even
during this perturbed time he prosecuted his studies and teaching. Every
evening extracts from his great works, the _Canon_ and the _Sanatio_, were
dictated and explained to his pupils; among whom, when the lesson was over,
he spent the rest of the night in festive enjoyment with a band of singers
and players. On the death of the amir Avicenna ceased to be vizier, and hid
himself in the house of an apothecary, where, with intense assiduity, he
continued the composition of his works. Meanwhile, he had written to Abu
Ya'far, the prefect of Isfahan, offering his services; but the new amir of
Hamad[=a]n getting to hear of this correspondence, and discovering the
place of Avicenna's concealment, incarcerated him in a fortress. War
meanwhile continued between the rulers of Isfahan and Hamad[=a]n; in 1024
the former captured Hamad[=a]n and its towns, and expelled the Turkish
mercenaries. When the storm had passed Avicenna returned with the amir to
Hamad[=a]n, and carried on his literary labours; but at length, accompanied
by his brother, a favourite pupil, and two slaves, made his escape out of
the city in the dress of a Sufite ascetic. After a perilous journey they
reached Isfahan, and received an honourable welcome from the prince. The
remaining ten or twelve