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

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33 modern inches or angulas are equal to 80 angulas
of Bhāskara as per the above.
At this rate the gnomon's modern length would be
just 5″.}
Reverting to our subject, we are asked to represent the
disc of 30 liptas when the eclipse takes place at noon by
30/3½ angulas counting at the rate of 3½ liptas per angula.
Then the question arises as to what should be the
correspondence between the liptas and angulas when the
eclipse takes place in between the rise of the Moon (or Sun)
and its noon. The directive is that
one angula = 2½′ + (H cos z) / R = 2½ + cos z I
This means, supposing Z=zenith-distance of the body
to be 60°, one angula is to be taken to be equal to
2½ + cos 60 = 2½ + ½ = 3′ or 3 liptas.
The reason given by Bhāskara reiterating what Sri-
pati said in that behalf, as to why the Moon's or Sun's
disc appears to be big at the moment of rising and small
on the meridian, is that the disc is immersed in its own
rays at noon and rendered small in appearance, whereas,
most of the rays are swallowed by the earth or its atmos-
phere at the moment of rising, making the disc appear
large and easily visible.
Note. Bhāskara gives the proof of the above formula
I as follows. Since at the time of rise, we are taking 2½
liptas of the measure of the disc to be equal to one angula
and while the disc is on the meridian, 3½ liptas are to be
taken as one angula, there is an increase of one lipta for
an increase of H cos z from zero at the horizon to a value
equal to the Radius. So, the argument adduced is 'If for an
increase of H cos z equal to the radius, there is an increase