Bīrūnī, Muḥammad ibn Aḥmad, Alberuni's India (v. 1)

(London :  Kegan Paul, Trench, Trübner & Co.,  1910.)



Jump to page:

Table of Contents

  Page 282  

282                           ALBERUNPS INDIA.

digression, and compel him to prove the cause, not of
the first, but of the second motion. The latter cause is
the cycles of the planets, which have only a relation to
the sphere, not to the earth. These cycles Balabhadra
indicates by the word kalpa (v. p. 279), since it com¬
prehends them all, and since all of them begin with its
Thomcri-         If  Brahmagupta   says  of  the   meridian  that it is

into sixty'^ divided into sixty parts (v. p. 279), it is as if any one of
giaya. ^^ should Say, the meridian is divided into twenty-four
parts ; for the meridian is a medium for measuring and
counting time. Its revolution lasts twenty-four hours,
or, as the Hindus will have it, sixty ghatikd (or ghari).
This is the reason why they have reckoned the risings
of the zodiacal signs in ghatikd, not in times of the
meridian (360 degrees).
Ontbefixed If, further, Brahmagupta says that the wind causes
the fixed stars and the planets to revolve, if he besides,
in particular, attributes a slow eastward motion to the
planets (p. 280), he gives the reader to understand that
the fixed stars have no such motion, or else he would
have said that they, too, have the same slow eastward
motion as the planets, not differing from them save in
size and in the variation which they exhibit in the re¬
trograde motion. Some people relate that the ancients
originally did not understand their (the fixed stars')
motions until, in long periods of time, they became
aware of them. This opinion is confirmed by the fact
that Brahmagupta's book does not, among the various
cycles, mention the cycles of the fixed stars, and that
he makes their appearing and disappearing depend
upon invariable degrees of the sun.
Thedirec-         If Brahmagupta maintains (p. 278) that to the in-

heaveniy'^    habitants of the equator the first motion is not a motion
Sseen'from to the right and left, the reader must bear in mind the
points'of     following.    A man dwelling under either of the two
^^^^ ^-     poles, to whatever direction he turns, has always the
  Page 282