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

10 PAÑCASIDDHĀNTIKĀ I.10 counted from Caitra and the tithis from Śukla Pratipad. The moment of Epoch is given as mid- sunset at Yavanapura, because the Sun has an angular diameter of about 32', and the time between the beginning and end of its immersion below the horizon is considerable. The practice of beginning the day at sunset was, in those days, prevalent in the countries near Yavanapura, which practice is still followed by Jews and Muslims, as in India certain Siddhāntas like the Sūrya Siddhānta begin the day at midnight, which is used for certain injunctions of the Dharma-śāstras, while certain other works like the Āryabhaṭīya etc. begin the day at sunrise which is used for certain other injunctions of the Dharma-śāstras. Yavanapura is Alexandria in Egypt, the ancient capital of the country, where Ptolemy II, the famous astronomer and author of the Almagest, ruled and which was well known to the astronomers of India. How do we know that it is Alexandria and no other city? In III. 13 the time-difference between Yavanapura and Ujjain due to their difference in longitude is given as seven nāḍīs and twenty vināḍīs and sunset at Yavanapura is later. From this we can see that it must be a well known place 44° west of Ujjain in longitude and its position agrees with that of Alexandria. We have said that the moment of Epoch begins Monday, somadivasādye. This reading is that of Bhaṭṭotpala, quoting the verse in his commentary of the Bṛhatsaṃhitā and we have adopted it as the correct one. It does not matter if we adopt another reading, saumyadivasādye, for we can interpret this as 'the day pertaining to the Moon', i.e. Monday, because the word saumya can be interpreted as 'belonging or pertaining to the Moon'. It cannot mean Wednesday, as it might appear at first sight, (the word saumya being a name for Mercury), for it must be Monday because the Lord of that day as computed from I.20 is the Moon and not Mercury. We shall show how. In I.17 it is instructed that 2227 should be added to the Days from Epoch to get the lords of the year, month, day and horā. Because the Days from Epoch gone is patently zero at the Epoch itself, we have 2227 + 0 = 2227, from which to get the Lord of the day. The instruction is to divide this out by seven, and take the remainder, which gives the Lord of the day gone counting from the Sun, in the order Sun, Moon, Mars etc. Now we want the Lord of the 2228th day, and dividing 2228 by 7, the remainder is 2, i.e. Moon is the Lord of the day and it must be Monday. This can be shown in other ways also but this is enough here. When there is this fact of a Monday and the reading somadivasādye to support it, the interpretation by some as 'at the beginning of Wednesday' has to be discarded. There is another reading, bhaumadivasa which has been accepted by the two scholars, S.B. Dikshit and Bhau Daji, and also by NP, not remembering that the formula has been and can be constructed only on the basis of the mean constants and not of the true constants and not understanding the purpose of the statement caitraśuklādau, as such that reading has also to be discarded. Note also that the Romaka ahargaṇa mentioned in verse 17 below, viz. 2227, works out only to Monday, not Tuesday, since the cycle commences from Sunday. We have given as one interpretation of nāticire Pauliśe 'py evam, 'It can be taken as the Pauliśa rule also, provided the time taken for computation is not very far from the Epoch'. Strictly speaking, in the rule given by a particular Siddhānta, only the synodic month and the tithi of that Siddhānta must be used to get the Days from Epoch. But as given in I.4, the tithi of the Romaka was near that of Pauliśa at the time of Epoch and so the Romaka rule could be used for the Pauliśa for some time, especially because there is the check by comparing the week-days. Another thing to be noted is this: Whatever Siddhānta is used to compute the days from Epoch, the result must be the same. That is why no separate rule has been given either for the Vāsiṣṭha or for the Saura, for we can use days of the Romaka or Pauliśa for these also, mutatis mutandis. TS interpret nāticire Pauliśe' py evam as 'the rule is the same for also the Pauliśa Siddhānta which was