सिद्धान्तशिरोमणि: गणिताध्याय (भास्कराचार्य - ग्रहगणित, मध्यमाधिकार व स्पष्टाधिकार सटीक)

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If a moment in between the Sammīlana and Unmīlana
were taken, the then Bhuja and Koṭi could be no doubt
computed, but the question of magnitude of the eclipse
does not arise as the entire disc has been plunged in the
shadow.
Second half of verse 31 verse 32 and first half of verse
33. Alternative method of depicting the eclipse geo-
metrically.
Joining the upper end of the latitude of the middle
moment of the eclipse to those of the first and last
contacts, we have what are called the Pragrahamārga and
Mokṣamārga ie. the path of the centre of the eclipsing
body from the first contact to the middle moment of the
eclipse and that from the middle moment to the last
contact. The lengths of these paths could be computed
and they could be drawn before hand. Then with the
centre of the Moon as centre and radius equal to p—r, if
a circle be drawn, it cuts the paths described above each
in one point. With those points as centre and radii equal
to p, if circles be drawn, they will touch the Moon’s disc
each in one point which are respectively the points of
Sammīlana and Unmīlana.
Comm. In as much as the latitude of the Moon
differs from moment to moment, the Pragrahamārga and
the Mokṣamārga are separated to achieve a little more
accuracy than could be got by joining the upper extre-
mities of the initial and final latitudes. The remaining
statement is evident, for, at the moments of Sammīlana
and Unmīlana, the distance between the centres of the
eclipsing body and the eclipsed will be p—r, so that the
points of intersection of the Pragrahamārga and Mokṣa-
mārga with the circle whose centre is the centre of the
eclipsed body and radius p—r will give the centre of the
eclipsing body.
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