" 196 RISING, SETTING AND CONJUNCTION OF PLANETS Details of the method of successive approximations contem- plated in the above rule: 34. Find out the displacements of the Sun and the Moon for the ghatis (corresponding to the approximate time) obtained above and add them to the longitudes of the Sun and the (visible) Moon respectively; then determine the ghatis (due to the oblique ascension of the part of the ecliptic) intervening between them; and then from those (ghatis) subtract the length of the day. (Thus is obtained the second approximation to the required time). Then find out the the displacements of the Sun and the Moon corresponding to (the ghatis of) the remain- der (and proceed as above again and again until the successive approximations agree to vighatis). An analogous rule for finding the time of moonrise in the light half of the month (II quarter): 35-36. (In the light half of the month) when the measure of the day exceeds the nadis (due to the oblique ascension of the part of the ecliptic) lying between the Sun and the (visible) Moon (computed for sunset), the moonrise is said to occur in the day when the residue of the day (i.e., time to elapse before sunset) is equal to the ghaiis of their difference. (In this case) the longitudes of the Sun and the (visible) Moon should be diminished by their displacements determined by proportion from the nadis (of the residue); and then should be obtained the asus (due to the oblique ascension of the part of the eclip- tic) between the Sun and the (visible) Moon (thus obtained). These asus should then be operated upon by the method of successive approximations. Another rule for getting the time of moonrise in the dark half of the month (IV quarter): 37-38. Determine the asus. (due to the oblique ascension of the part of the ecliptic lying) from the (visible) Moon at sunrise up to the rising Sun; then subtract the corresponding displacements (of the Moon and the Sun) from them (i.e., from
