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No. 6.]
THE FIRST ARYA-SIDDHANTA, MEAN SYSTEM.
21
Mesha-sankranti, the value of a at mean sunrise of the former, and the required week-day. The second process is, using Table LXXIX, to find such earlier day as by adding its a to the a of Měsha-samkrinti, already found, will yield a result between 0 and 3333. The Table then shews the interval of days between the two sunrises, and the week-day corresponding to Chuitra Bukla 1.
A. Take for instance the year K.Y. 3725 expired, A.D. 624-25. Mean Měsha-samkrinti ocourred in that year (Table LXXVI, cols. 13-17) on Wed, 21 Mar., -serial day 81, from Jan, 1. We take the value of a at mean sunrise at the beginning of the Kaliyuga century and at the beginning of the expired year from Tables LXXVIII and LXXIII respectively. The result gives the value of a at mean sunrise of Měsha-samkrānti day in the given year,
- w-d. a. . (Table LXXVIII). K.Y. cent. 37. . . . (1) 6583.1816 (Table LXXIII above). K.Y. year 25
(8)
2047.6413 At mean sunrise on Wed. 21 Mar., the day of occurrence of mean Mēsha-samkrānti . . . . (4) 8630-8229
Process 1. (Table LXIV above). Next lower value of a in the first
30 days of the Table, i.e. that for 25 days .-(4) - 8465.7968
At mean sunrise of the day Chaitra sukla 1 . . (0) 165-0261 This Chaitra sukla 1 civil day was (81 - 25=) Day 56, or (Table IX, Indian Calendar, or LXIX above) Sat. 25 Feb. A.D. 624.
Process 2. At mean sunrise on Wed. 21 Mar., the day of mean
Mēsha-sankranti (as above). . . . (4) 8630-8229 (Table LXXIX). The only value of a which yields
result between 0 and 333-3 . . . . . +(3) +1534.2032
At mean sunrise of the day Chaitra sukla 1 . . (0) 165 0261 Table LXXIX shews that the interval of days was 25, and the result is in all respects the same as the former.
B. Calcnlation for the mean sunrise value of a on the day of mean Mosha-samkranti, the first step shewn in the above, by use of Tables LXXVIII and LXXIII sometimes results in the day found being not the actual day on which Mēsha-samkrānti took place but the day next to it. This is inevitable, seeing that only one Table has to stand for the odd years of all centuries. In such case the necessary adjustment must be made for one day's difference. The entries in Table LXXVI, cols. 13 to 17, are conclusive as to the actual day.
Take the year A.D. 625-26, K.Y. 3726 expired. In that year mean Měsha-samkrānti occurred on Thurs. 21 Mar., serial day 80.
w-d. (Table LXXVIII). K.Y. century 37 . . . (1) 6589.1816 (Table LXXIII). K.Y. year 26 . . . . (5) 59869072 At mean sunrise of Friday, 22 Mar..
2570-0888 Deduct value for one day (Table LXIV). . . (1) -338-6819 At m. sunrise of Thurs. 21 Mar., the day of mean Mösha-samkranti . . . .
. (5) 2231.4569