274 Journal of the Asiatic Society of Bengal. [N.S., XVU, 
Sloka, it is learnt that the Spee. if not the date of composi- 
tion, must have been 961 Saka (1039 A.D.). But as no pecul- 
iar phenomenon i is associated with this year, as it is uot divisi- 
ble by 60, nor does it end in two cyphers (considerations g ee 
ally influencing an Astronomer in the choice a an Epoch), i 
may be assumed unless any positive evidence the eee: 
is forth-coming that this must also have been ite date of com- 
position. The - aE treatise was thus most probably composed - 
at the ripe a 
Method of ilewekion —-(1) The first step is to determine 
the number of lunar months from 961 Saka to the date on 
which we are investigating the occurrence of an eclipse. ‘The 
number of solar years intervening is multiplied by 12, the 
ting the total number of solar months. This is multiplied 
by 2, 5 is deducted from the result, 916th part of the difference 
is deducted from dee igs difference is divided by 65. Then 
this quotient adde e number of solar months gives the 
number of lunar ee This is, but for a small correction, 
equivalent to adding two lunar months to every 65 solar 
m 
hs, 
(2) The next step is the determination of the diflerence 
in longitude of the Moon and its Node. From what is given 
we learn that the Moon separates from its Node in every Tunar 
(synodic) month by 2 naksatras-18 naksatramsas (60th parts of 
a naksatra)—1 and 1/20 (8600th parts of a naksatra). A peculi- 
arity of “ Dhikoti’ lies in the fact — the difference of the 
longitudes for every lunar synodic month is expressed in sex- 
agesimals of a naksatra ( 13 degrees 20 titieion, and not in sex- 
agesimals of a degree as usual. The reason will appear later: 
Now 2"-18”’-1 and 1/20” multiplied by the number of lunar 
months obtained before gives the total difference in longitudes 
the Moon and its Node, omiting complete revolutions, for 
the period in Naksatramsas. Add to this the original differ- 
ence in longitudes, which is given as 1-44-6. The sum will 
give the difference at the end of the lunar month or at 
Amavasya. If we want the difference for the next Purnima, 
we are to add further 1-9-0, ie. half of 2-18-1 & 1/20 for half 
a lunar month. 
(3) Then a further correction is es according as the 
Sun is in one or other of the following signs 
Signs Subtractive Signs Additive 
(naksatramsas) (naksatramsas) 
Karka ey O34 Makara 6-0 
Simha — es Se ee Kumbha 010 0 
Kanya 010 0 Mina - 011 0 
ula O16 Mesha ne 010 0 
Vrischika 0 8 0 Vrisa vd 6 6 0 
Dhanu 0 3.0 Mithuna p20 0: 
