158 ECLIPSES From the asus intervening between midday and the tithyanta ("the time of geocentric conjunction of the Sun and Moon") one should subtract in the forenoon the asus correspon- ding to the degrees traversed of the sign occupied by the Sun (at the tithyanta) and in the afternoon the asus corresponding to the degrees to be traversed. The degrees (traversed or to be traversed) should be (respectively) subtracted from or added to the longitude of the Sun (for the tithyanta). The complete signs determined with the help of the asus of the right ascensions of the signs and whatever (fraction of a sign) is obtained by pro- portion should also be (respectively) subtracted or added by those who know the true principles of the science of time. This (i.e., the longitude thus obtained) is the true (sayana) longitude of the meridian-ecliptic point. So has come out of the mouth of the illustrious (Acarya Ārya)bhaṭa.¹ The five Rsines relating to the Sun and the Moon: 12. The orbits of the Sun and the Moon being different, the (five) Rsines for them. are said to differ. This (difference) is indicated by the words "svadrkksepa etc." of the Master (Āryabhata I).³ The five Rsines contemplated here are the so called udayajyā, madhyajya, drkkṣepajyā, dṛgjyā and dṛggatijyā. Rules for finding these are gives in the next eleven stanzas. A rule for finding the Sun's udayaja: 13. Multiply the Rsine of the bahu due to the (sayana) longitude of the rising point of the ecliptic by (the Rsine of) the (Sun's) greatest declination and then divide (the product) by. (the Rsine of) the colatitude: the quotient is the Sun's true udayajyā.* 1 The Sun's longitude to be used in this rule must be sayana. 2 Lalla in his Śisya-dhi-vṛddhida takes for simplicity the five Rsines for the Moon to be the same as those for the Sun. 8 Vide A, iv. 33.
- This rule occurs also in ŠiDV₁, I, v. 4.
