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

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there is no parallax in latitude ie. no nati at all, as should
be the case.
Fig. 101 Fig. 102
Or, Bhāskara's argument could be better illustrated
from figure 102. Let VS be the ecliptic where V is the
Sun's Vitribha and S, the Sun. Let V'M be the Moon's
orbit called Vikṣepamandala where V' is taken to be the
Moon's Vitribha and M the Moon. Let S', M' be the
deflected positions of the Sun and the Moon on account of
parallax. ZV' = ZV + VV' = the arc of the Sun's Dṛk-
kṣepa + the latitude at the point V called Vitribhalagna-
Bāna, as formulated by Brahmagupta that ZV' is roughly
equal to the Moon's Dṛk-kṣepa-Dhanus. (Strictly speaking
ZV' ought to be perpendicular to the Moon's orbit V'M,
if V' were to be the Vitribha of the Moon; but, as the
latitude is small, the error is negligible). Let LS' and
L'M' be the so-called Krānti-Sadṛśa-mandala and Vikṣepa
Sadṛśamandala or parallel drawn to the ecliptic and the
Moon's orbit through the deflected positions S' and M' of
the Sun and the Moon. S'n is the Sun's parallax in latitude
ie. Nati. Similarly Brahmagupta took M'n' to be the
nati of the Moon as stated by Bhāskara. The error com-
mitted will be therefore M'n'— S'n = (M'x' + x'n') —
(S'x + xn) = M'x' — xn) cancelling x'n' and S'n which are
roughly equal. Also xn could be roughly taken to be equal