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EPIGRAPHIA INDICA.
From (9) and (5) we derive the true longitude of the sun by adding to the mean anomaly of the sun the equation of the sun, but with the sign changed, and then subtracting the mean anomaly of the sun for the beginning of the century. E. g. we have found that K. Y. 3585, Åshadha sudi 12, ended, according to the Brahma Siddhanta, 50 gh. 16 p. after mean sunrise at Lanka, and that at that moment the mean anomaly of the sun was 16° 4'61"; the corresponding equation is + 38' 58"; applying the equation with the sign changed, we have 14' 3053". By subtracting the mean anomaly of the sun for the beginning of the century, viz. 282° 6', we have the sun's true longitude 92° 24' 53".
53. True longitude of the Moon.-If we add the true longitude of the sun to the true distance between sun and moon (6), we get the true longitude of the moon, on which depends the Nakshatra and Rafi (see $ 6).
Here we have 144° + 92° 24' 58" = 288° 24' 53". The nakshatra is Jyeshţha (Table IX) and the rabi Tulå (Table XII). Adding the o's long. to the D's long. we find the Yoga, 236° 24' 53" + 92° 24' 53" = 328° 49 46", Yoga : Brahman (Table IX).
64. The Sankrdntis.-The time of all Samkrantis according to the Súrya Siddhanta is found in Table XX. If the time, according to another Siddhanta, is wanted, we can use the mean longitude of the sun as given at the same place; e.g. if it be proposed to find the moment of the Karkata Sankranti in K. Y. 4681, according to the second Arya Siddhanta, we calculate as follows:
4500 K, Y. O's Anom. . 282° 4' 2" Table XVII, Second Arya Siddhanta. Kark. Samkr.»
90° SUP 28"
12° 34' 30" Eq. 11° 15' = + 26' 28" Eq. . . . -0° 28' 18" + 1° 19' = 245*
12° 6' 17" Eq. 12° 34' = + 28' 13" Subtract mean an. O . . -282° 4' 2" True long. . . . 90° 2' 15"
At the moment assumed for the Sankranti, vis. o Sráv. 49 gh. 48 p., the Samkranti had passed, and the sun had advanced 2' 16" beyond the initial point of Karkata. According to Table XXII”, 2' 16" is equal to about 2 gh. 17 p. by which time therefore the Sankranti, according to the second Arya Siddhanta, preceded the moment calculated. The Samkranti oocurred therefore on 0 Sravana 47gh. 31p. This result however does not refer to mean sunrise at Lanka, but to the beginning of the mean solar year. In order to reduce the result to Lanká time, we must find the correction : 4500 = -6gh. 22p., 81 years = + 2gh. 40p., K. Y. 4581 = -8gh. 87p. Sunrise at Lanka preceded the beginning of the mean solar year by 8gh. 87p. Hence the Samkrånti occurred 479h. 31p. + 8gh. 87p. = 61gh. Sp. after mean sunrise at Lanká according to the second Arya Siddhanta.
58. Interoalary months. If we know the age of the moon at the beginning and end of a solar month, we can decide by the rules in $ 31, whether there was an intercalated month or not. We compute the tithi at the time of the two Sankrantis which
It may be remarked that the minutes and seconds of the mean motion of the sun Dearls correspond to as many ghatikde and palau.
