Suryasiddhanta 3.8

3.8

dvādaśāṅgulaśaṅkucchāyayorvargayogāt padaṃ chāyākarṇaḥ syāt | athāsya śuddhirūpaṃ chāyāsādhanamāha | asyeti | chāyākarṇasya vargāt śaṅkuvargaṃ catuścatvāriṃśadadhikaṃ śataṃ viśodhya mūlaṃ chāyā | prakārāntareṇa chāyākarṇaśuddhimāha | śaṅkuriti | viparyayācchāyāsādhanavaiparītyācchāyākarṇavargācchāyāvargaṃ viśodhya mūlamityarthaḥ || śaṅkurdvādaśāṅgulamitaḥ syāt | atropapattiḥ | dvādaśāṅgulaśaṅkuḥ koṭiratrabhābhujastatkṛtyoryogapadaṃ karṇa ityatrakarṇaḥ karṇa ityādyatracetrādyuktarītyopapannam | nanu diksādhanottaramiṣṭaprabhāyākarṇasādhanaṃ bhagavatā sarvvajñena kimarthamuktamagre'grādīnāṃ svatantratayoktatvāt | na ca vinā gaṇitamamagrājñānārthamidaṃ yuktamuktamiti vācyam | vakṣyamāṇabhujajñānasyāgropajīvyatvena tasyāśca bhujopajīvyatvenānyonyāśrayāt | gaṇitajñātāgrāyāḥ punaḥ sādhanasya vyarthatvācca | na ca bhujasūtrāṅgulairddānairityaneneṣṭacchāyāgraṃ jñātamiti na kintvetaduktyā dik‌sūtrasampātaspṛśaṅkorvṛttaparidhau chāyāgrajñānāt tatpūrvāparasūtrāntare bhujasadbhāvāddinā gaṇitaṃ bhujo'pi jñāta iti nānyonyāśraya iti vācyam | tathāpi bhagavataḥ sarvvajñasya niṣprayojanatvokteranucitatvāt | vinā prayojanaṃ mandokterapyabhāvācca | na hi dik‌sādhane'grābhujādikamāvaśyakaṃ yena taduktiryuktā | kiñca karṇasādhanasya gaṇitoktyā vakṣyamāṇakarṇa sādhanatulyatvenātra kathanamanucitam | na hi dik‌sādhanārthaṃ bhākarṇamityā hatāditi siddhāntaśiromaṇyuktivadatra chāyākarṇa upayukto yena taduktiryukteti caturasramityādiślokacatuṣṭayamanyena mandabuddhinā kṣiptaṃ na bhagavatoktamiti cennaivam | bhujasādhanopajīvyāgrāyā etaduktaprakāreṇa siddhau diśaḥ samyak siddhā iti diksādhanaśuddhyarthamagrāsādhanam | prakārāntareṇāpi vakṣyamāyatrijyāvṛttīyāgrayā trijyā labhyate tadānayāgatayā ketyanupātena sādhitakarṇasaṃvādena śuddhayavagamārthaṃ karṇasādhanaṃ coktam | anayāgrayā karṇastadā trijyāvṛttīyāgrayā ka iti phalasya trijyātutyasyānayanārthaṃ vā karṇasādhanamiti kecit | vastutastu maṇḍale chāyāpraveśanirgamasthānasthitapūrvāparavindvoḥ pratyekaṃ rekheti rekhādvayaṃ sarvvatastulyāntaraṃ kāryaṃ tenāntararekhānyataro vinduścālyastau pūrvāparavindū tadrekhā madhyasthānasya pūrvāpararekheti | tatrobhayavindurekhayorantarāṅgulamānaṃ svalpatvādgaṇayitumaśakyamataḥ pratyekarekhe prācyapararekhe prakalpya tanmadhyakendrāt pūrvvavṛttaṃ pratyekamiti vṛttadvayaṃ kuryāt | tatra svasvavṛtte svasvaprācyapararekhā spaṣṭā kāryā tābhyāṃ svasvakālikau bhujau svasvavṛtte deyau tadagre chāyāgrarekhe svasvavṛtte kārye svasvaprācyaparasūtrāt svasvavṛtta uttarabhāge'kṣabhāṅgulāntareṇa rekhe kārye tataḥ svasvavṛtte svasvadrekhayorantaraṃ svasvavṛtta ubhayakālikakarṇavṛttāgre aṅgatvena gaṇayituṃ śakye tadantaraṃ pūrvvavindvoryāmyottaramantaraṃkarṇavṛttāgrāsādhanakathanenānītaṃ bhujāntarasya vindvantaratvāt tasya cāgrāntaratvena phalitatvāt | viṣuvaddine golabhede tu bhujāntaramagrāyoga iti vindvoryāmyottaramagrāyoga iti | tenoktararītyā vinducālyastatsūtraṃ pūrvāparasūtraṃ sphuṭamityāśayena bhagavatāgrā nirūpitā tasyāḥ śuddhyarthaṃ karṇo'pi sādhita iti tattvam |
atha pūrvādhikāre krāntyādyānayanamuktaṃ tat pūrvādhikārāvagatagrahāt kevalānna sādhyamiti ślokābhyāmāha |