Page:Sewell Indian chronography.pdf/98

There having been no year 0 between 1 B.C. and A.D. 1, we have to add one year to the interval from 500 B.C. to the selected year. We take two 576-year intervals. 576 × 2 + 1 1153 years. 1153 − 500 = A.D. 653. The Ārya Siddhānta Mēsha saṁkrānti in A.D. 653 took place (Table I.) on March 19th, Tuesday, at 22 h. 32 m. For two periods of 576 years each, deduct 10 days from the day of the month and 8 week-days from the week-day. Therefore the M.S., by the Ār. Siddh., in 500 B.C. took place on Monday, March 9th, at 22 h. 32 m. [And the M.S. in A.D. 77, which was removed from 500 B.C. and from A.D. 1153, by one period of 576 years took place on March 14th, Friday, at 22 h. 32 m.]

Example 4.—To find the time of true sidereal Mēsha saṁkrānti by the Sūrya Siddhānta in a similar year.

Rule. Find the moment of true Mēsha saṁkrānti by the Ārya Siddhānta as directed in Example 3, and convert it to the same according to the Sūrya Siddhānta by use of the Table on p. 55 of the Indian Calendar. The two authorities were together in A.D. 496. The Table gives the difference between them for years earlier or later, measured by the number of years intervening between A.D. 496 and the given year.^[1] (§§ 47, 56.)

Wanted the moment of Mēsha saṁkrānti according to the Sūrya Siddhānta in 500 B.C. (K.Y. 2602 expired), and the day of the week.

We found in the last example that the Mēsha saṁkrānti in 500 B.C. according to the Ārya Siddhānta occurred on Monday, March 9th, at 22 h. 32 m. The interval between 500 B.C. and A.D. 496, there being no year A.D. 0, is 995 years. And from the Table on p. 55, Ind. Cal., we have, for 900 years, 90 years and 5 years respectively, 1 h. 38.4 m., 9.8 m. and 0.5 m. Total, 1 h. 48.7 m., or, roughly, 1 h. 49 m. Deducting this from the Ārya-Siddhānta-time, we have, for the moment of Mēsha saṁkrānti in 500 B.C. by the Sūrya Siddhānta, March 9th, Monday, at 20 h. 43 m. Laṅkā time.

Example 5.—To find the time of mean sidereal Mēsha saṁkrānti according to the Ārya Siddhānta for any year. [See § 26, pp. 11, 12 of the Ind. Cal., and §§ 57–62 above.]

Rule. Find the time of true sidereal Mēsha saṁkrānti according to the Ārya Siddhānta from Table I., cols. 13 to 17, or by Example 3 above. Add to this the śōdhya difference according to that authority, viz., 2 d. 8 gh. 51 p. 15 v., or 2 d. 3 h. 32 m. 30 s. This gives the time of mean Mēsha saṁkrānti

(a) Wanted the time of mean Mēsha saṁkrānti of K.Y. 4041 expired, A.D. 940.

(b) Wanted the time of mean Mēsha saṁkrānti of K.Y. 0 expired, or 1 current = the epoch of Hindu astronomy. Work by Example 3. Six cycles of 576 years = 3456 years. The corresponding year of Table I. is K.Y. 3456 expired, or 3457 current. For the day of the month we deduct (6 × 5) 30 days, and for the day of the week (6 × 4) 24 days, retaining the hours and minutes given.

1. ↑ Table XVII. is based on these figures of difference, but it only concerns the 1600 years of Table I. The Table on p. 55 enables the difference to be found for any number of years intervening between the given year and the base year.