1884.] G. Tliibaut —Vardha Mihira’s Panchasiddhdntilcd. 
280 
tika is that the latter work quotes Arya Bhata who was born in 476 only 
and therefore is not likely to have been referred to in 505 already as a 
writer of authority. Matters lie, however, somewhat difcerently. We 
know from a passage of Brahmagupta which Vv^ill be quoted later on, that 
S'rishena the author of the Bomaka Siddhanta had borrowed some of 
the fundamental principles of his astronomical system from i^ryabhata. 
Bow Aryabhata’s first work (for it is not likely that he began to write 
before the age of twenty-three) having been composed in 499, the assump¬ 
tion that 505 marks the time of the Pauchasiddhantika would compel us to 
conclude that Shishena’s work was written in the short interval between 
499 and 505, and had then already become famous enough to be esteemed 
one of the principal five Siddhantas. Such a conclusion does certainly 
not recommend itself, and we may safely I think assume that 505 is either 
the year in which Srishena’s work was written or else the year selected 
by him for the starting-point of his calculations, and therefore not far 
remote from the year in which he wrote. For the date of the Pahcha- 
siddhantika there would finally remain the period from 505 to 587. I 
should, however, be unwilling to assign it to a later date than perhaps 
530 to 540 ; for if its composition was removed by too great an interval 
from 505, it is improbable that Varaha Mihira should have kept the latter 
year as his epoch and not have introduced a more recent one. 
We return to the ahargana rule. The days are to be counted from 
sunset, a practice which we do not elsewhere meet with in India while 
it is known to have been generally followed by the Greeks ; another 
proof for the particularly intimate dependance of the Bomaka on Greek 
science. The years which have elapsed from the epoch are turned into 
months (in the usual way, by being multiplied by 12) and the elapsed 
months of the current year are added. Then by a proportion resulting 
from the yuga of the Bomaka the intercalary months are calculated (7 
intercalary months are to be added to 228 months ; how many to the 
given number of months ?). The number of the months is then multi¬ 
plied by 30, and from the number of tithis found in that way the num¬ 
ber of omitted lunar days (tithi kshaya) is derived by another propor¬ 
tion, which is, however, merely approximate. Since, as we have 
seen above, the Bomaka reckons 16,547 omitted lunar days to the 
yuga (which comprises 1,057,500 tithis), 703 lunar days comprise 
41 
11 H-omitted lunar days, while the proportion made use of 
1057500 ^ 
for the calculation of the ahargana neglects the fraction. The additional 
quantity 514 does not occupy us because, as stated above, we exclude for 
the present the consideration of the epoch of the Bomaka Siddhanta 
and the kshepa-quantities connected with it. 
