Suryasiddhanta 3.5

3.5

madhyādabhīṣṭasthānāddigrekhāsampātarūpādinirgatairnisṛtairaṣṭadigrekhārūpaiḥ | bahirdikasūtrasampātakendravṛttādvahiḥ | anenaiva vṛttakaraṇaṃ pūrvamanuktaṃ dyotitam | anyathā bahirityasyānupapatteḥ | pūrvavṛttagrahaṇe tu digrekhāsampātasya madhyatvānupapatteḥ | caturasraṃ koṇarekhādhikasūtrakarṇadvayatulyaṃ samacaturbhujaṃ kuryāt | yathā ca taddarśanam | tatra caturasre bhujasūtrāṅgulairvakṣyamāṇabhujamitasūtrasyāṅgulairnirgamapraveśakālikairdattaiḥ pūrvāparasūtradardhajyāvaddīyamānaistatra vṛtte yasmin pradeśe bhujāgraṃ tatpradeśa iṣṭaprabhā nirgamapraveśānyatarakālikacchāyāgramuktam | pratītistu dik‌sūtrasampātasthaśaṅkunā jñeyā | atropapattiḥ| vakṣyamāṇabhujasya chāyāgrapūrvāparavṛttāntaratvena pratipāditatvādiṣṭacchāyāgramuktadiśā jñātaṃ samyak | caturasrakaraṇaṃ vakṣyamāṇāgrāsādhakaprācyapararekhānukārarekhāyā vṛttāntastadvahirvā ṛjutvasiddhyarthamiti |
atha pūrvāpararekhāyāḥ sañjñāntaramāha |