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

237 the shadow, ☉ = the position of the Sun whose zenith- distance is ☉ z. If z' be taken as the zenith ☉ z' meas- ures the zenith-distance whereas if z be taken as the zenith ☉ z is the zenith-distance. The apparent inconsistency that both ☉ z' and ☉ z are taken as the zenith-distance is not there if we consider the ^ ^ zenith-distance as the angle ☉ nz' = ☉ oz. O ☉ = R, ☉ z = z, so that ☉ L = H sin z, and LO = ☉ M = H cos z = Śanku or Nara or Nā. it is called Nara or Nā which means man, because a man may consider himself as a gnomon, which is called Śanku. So the word is also applied to the parallel H cos z parallel to the gnomon and called Mahāśanku. H sin z is called Drigjyā (9) zenith-dis- t