पञ्चसिद्धान्तिका (आचार्य वराहमिहिर - सूर्य, रोमक, पौलिश, वासिष्ठ एवं पितामह सिद्धान्त)

242 PAÑCASIDDHĀNTIKĀ XII.2 The period after which the Sun, Moon, and the planets all meet again at the first point of the zodiac is commonly called the yuga, meaning "the period of union." Here this is meant for the Sun and Moon alone, and this Siddhānta takes it to be five years, approximately, with a view to convenience. In the same way, the statements that there is an intercalary month after every thirty months, and an omitted day for every 62 lunar days, are approximate, and rounded off for convenience. The first tithi of the light fortnight of Māgha begins the yuga, and the year and the day begins with sun- rise. The author has not mentioned the number of intercalary months or days in the yuga, nor has he given how to get the 'days from epoch', expecting the readers to be experienced enough, by now, to know it for themselves. He has indicated it in I.16, and we have explained it under I.14-17. The only thing that is necessary is to know the years of the beginnings of the yuga, and this has been given here as two years after the śaka epoch, and every five years thereafter. We shall first compute the number of the intercalary months etc in the Yuga. The number of years in the yuga is 5, given. The solar months are 5 × 12 = 60. The intercalary months are, 60/30 = 2. The lunar or synodic months are, 60 + 2 = 62. The lunar days or tithis are 62 × 30 = 1860. The omitted lunar days are, 1860 ÷ 62 = 30. The (civil) days are, 1860 - 30 = 1830. The Moon's revolutions are, the Sun's revolutions + the synodic months = 5 + 62 = 67. The Vyatīpātas are, solar revolutions + lunar revolutions = 5 + 67 = 72. The number of days in the solar year is, 1830 ÷ 5 = 366. The days per ayana are 366 ÷ 2 = 183. This is enough for our purpose. To get the 'days':- (i) (Elapsed śaka years — 2) ÷ 5. Take the remainder alone. (ii) The solar months gone = (i) × 12 + elapsed months from Māgha. (iii) The intercalary months = (ii) ÷ 30. Take the quotient alone. (iv) The lunar months gone = (ii) + (iii). (v) The lunar days gone = (iv) × 30 + tithis gone in current month. (vi) Omitted days = (v) ÷ 62. Take the quotient alone. (vii) The days from epoch are, (v) - (vi). The tithis gone, used in (v) are actual elapsed tithis, and not those increased by one (according to verse 4. of this chapter,) for calendrical purposes. If the latter is used, subtract the calendrical elapsed tithi from the remainder got in (vi). If this is greater than 46, lessen the days from epoch by one to get the correct days. The reason for this will be explained while dealing with verse 4, following. Further, since there can be no fraction of intercalary month or avama at the beginning of a yuga carried over from a previous yuga, there is no kṣepa for these, in the computation rules. As for the explanation of these rules it has already been given in chap. I, when dealing with the rules for days from epoch according to the Romaka. The names of the five years, (not given in the text,) are: Saṁvatsara, Parivatsara, Idāvatsara, Anuvatsara, and Idvatsara. In certain Vedic śākhās, there is a slight variation in some names. As for the reading of the text, we have corrected dyūnam, into dvyūnam, since the former is meaningless in the context.