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

100
has stated. Bhāskara's statement yet has another mean-
ing. The ecliptic from 180° to 360 being in the reverse
as can be seen in fig. 27, the time by which a particular
Rāsi rises, is equal to the time by which its seventh Rāsi
or diametrically opposite Rāsi sets. It is important to
note that the rising time of a particular Rāsi is not equal
to its setting time as can be gauged from the rising times,
for, then the rising times of Meṣa and Tulā must be equal
which is not the case. The word विलोमसंस्थाः has this
meaning as well, rising and setting being reverse directions.
Incidentally there is what is called a वृद्धकारिका
handed down i.e. a traditional statement which men-
tions "मीनमेषौ चतुर्नड्यः सार्धं चत्वारिगोघटौ etc." This
clearly pertains to the local rising times of the Sāyana
Rāsis at a place of latitude 17°-45' i.e. in between
Rajamundry and Vizianagaram, as in this latitude the
chara Segments in asus will be 230, 184, 73 which give
rise to such rising times.
We next find what are called Nirayana Swōdayas i.e.
the rising times for the locality of the Nirayana Rāsis i.e.
the Rāsis from the zero-point of the Hindu zodiac. We
shall obtain these magnitudes for Rajahmundry whose
latitude is 17°-2'. We shall however take it as 17°; also
we shall take the Ayanāṁsas to be 21° at present following
Varāhamihira. This is one of the contexts where the
knowledge of Ayanāṁsas is essential. The method is the
same as followed before; only, we have to find the decli-
nations, right ascensions, charas and therefrom the rising
times of arcs of magnitude 21°, 51°, 81°......351°. Sub-
tracting the preceding rising times from the following we
have successively the required rising times. We shall
give them under the following table.