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

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



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364                          ALBERUNTS INDIA.

976/JjT' which is equivalent to 9y6-^rfiJ',j.     Vide p. 24
1.53 (Schram).

P. 22, 1. 17.—Read 22''i instead of 23"' (Schretm).

P. 23. PadamtXset.—Thi^ seems to be an old mistake
which has crept into the Arabic manuscripts of the works
of Alfazari and Ya'kub. Cf. the author's "Chronology"
(English edition), p. 15.

P. 27.—The rule given in the first fifteen lines of this
page is completely erroneous, and consequently the ex¬
ample calculated after this rule is so too. The right
method would be the following :—■" The complete years are
multiplied by 12; to the product are added the months
which have elapsed of the current year. The sum repre¬
sents the partial solar months. You write down the
number in two places ; in the one place you multiply it
by ^'^11, i.e. the number which represents the universal
adhimasa months. The product you divide by 172,800,
i.e. the number which represents the universal solar
months. The quotient you get, asfetr as it contains com-
qilete months, is added to the number in the second place,
and the sum so obtained is multiplied by 30; to the pro¬
duct are added the days which have elapsed of the current
month. The sum represents the candrahargana, i.e. the
sum of the partial lunar days." These two proceedings
would be identical, if we were not to omit fractions ; but
as an adhimasa month is only intercalated when it is com¬
plete, we must first determine the number of adhimasa
months, and, omitting the fretctions, change them to days;
whilst when we multiply beforehand by 30, the fractions
of the adhimasa months are also multiplied, which is
not correct. This is at once seen in the example which
he works out after this rule, and we wonder that Albe¬
runi himself did not see' it. He is calculating the ahar-
ganas for the beginning of a year, consequently also for
the beginning of a month, and, notwithstanding, he is not
at all surprised to find (p. 30) 28 days and 51 minutes of
the month already passed.

The adhimasa days are nothing else than adhimasa
months converted into days.    As the number of the adhi-
  Page 364