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

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In the second example cited by Bhāskara the Ecliptic
coincides with the horizon, the pole of the Ecliptic being
in the zenith. Then in a Solar Eclipse the Moon eclipses
the Sun from the south showing that H sin V = R. That
H sin V = R is also evident from the fact that the Ecliptic
makes 90° with the prime-vertical, having coincided with
the horizon. But here according to Lallāchārya’s formula,
H sin ξ = Hvers 90° = R and Āyana Valanajyā is Hvers δ,
where δ is the declination of a point whose longitude is
90° more than ☉. If ☉ = 30°, 60° H sin θ =
R/2 sin ω/R or (√3/2) (R sin ω)/R ie. (sin ω)/2 or √3/2 sin ω.
Evidently the sum of the two Valanas Āyana and Ākṣa
cannot be 90° as is also vouchsafed from geometry. So,
here also, the flaw is evident.
Note 1. Śrīpatyāchārya also followed Lallāchārya
vide verses 18, 19, 20 Chandragrahaṇādhyāya, Siddhānta
Śekhara. It will be noted that the commentator of
Siddhānta Śekhara, while reiterating Bhāskara’s stand as
the correct one, himself commits a mistake in saying
“सममण्डलीय नतांशज्यास्थाने नतकाकोत्क्रमज्या गृहीता” In fact
sin ξ = (sin ϕ sin h) / cos μ = (sin ϕ sin z) / cos δ as proved by us before.
The commentator cited above overlooked that sin ξ could
be also equal to (sin ϕ sin h) / cos μ , wherein natakāla also is
implied.
Note 2. It will be noted that even Pṛthūdakāchārya,
while commenting on Brahmasphuṭa Siddhānta, ignored
Brahmagupta and followed Lallāchārya blindly.
Note 3. The formula given by Lallāchārya and
followed by Pṛthūdaka as well as by Śrīpati is very rough
besides containing the flaw cited, in as much as both μ
and δ are taken to be zero, which are not so,