Bīrūnī, Muḥammad ibn Aḥmad, Alberuni's India (v. 2)

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



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70                         ALBERUNTS INDIA.

whilst Varahamihira reckoned the sun's distance from
the earth as 2,598,900, and the distance of the fixed stars
as 321,362,683. Thereupon Pulisa replied that the for¬
mer numbers were minutes, the latter yojctnas; whilst
in another passage he says that the distance of the fixed
stars from the earth is sixty times larger than the distance
of the sun. Accordingly he ought to have reckoned
the distance of the fixed stars as 155,934,000.
"Hindu             The Hindu method of the computation of the dis-

thecompu-  tauccs of the planets which we have above mentioned

tationofthe   .-i         -,                  ..,,.,.           ,                ,              •,!

distances of IS Dased ou a principle which is unknown to me m the

the planets.                  ,      ,             p           i           -.    -.               -.         ,                 t  i

present stage of my knowledge, and as long as i have
no facility in translating the books of the Hindus. The
principle is this, that the extension of a minute in the
orbit of the moon is equal to fifteen yojctncts. The nature
of this principle is not cleared up by the commentaries
Quotations   of Balabhadra, whatsoever trouble he takes.    For he

from Bala-                      -n        i       i                •    t           n        t          i

bhadra. says: " Peoplc have tried to fix by observation the
time of the moon's passing through the horizon, i.e. the
time between the shining of the first part of her body
and the rising of the whole, or the time between the
beginning of her setting and the completion of the
act of setting. People have found this process to
last thirty-two minutes of the circumference of the
sphere." However, if it is difficult to fix by obser¬
vation the degrees, it is much more so to fix the

Further, the Hindus have tried to determine by
observation the yojctncts of the diameter of the moon,
and have found them to be 480. If you divide them
by the minutes of her body, the quotient is 15 yojctnas,
as corresponding to one minute. If you multiply it by
the minutes of the circumference, you get the product
324,000. This is the measure of the sphere of the
moon which she traverses in each rotation. If you
multiply this number by the cycles of the moon in a
kalpa or caturyugct, the product is the distance which
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