Ashtangasamgraha 32.17

32.17

atha samasukhopaviṣṭasyopaviṣṭo vāmāṃguṣṭhena vartmottaramutkṣipya kṛṣṇabhāgasyādhaḥkanīnakādapāṅgaṃ yāvadañjanaṃ nayedanalpamaprabhūtamanatitakṣṇimanacchamasāndramakarkaśamadrutamavilambitamatiryagdṛṣṭyakampitamaghaṭṭitamanātrāntaṃ ca |

cūrṇe tu gatāgataṃ kuryāt |

anyathā hi rāgāśruśukrādyutpattiḥ |

tato 'ñjanānugamanāyānunmīlayan śanaiśśanairantaścakṣuḥ sañcārayet |

evamakṣyanugacchati |

vartmanī kiñciccālayet |

na tu sahasonmeṣaṇaniṣpīḍanaprakṣālanāni kuryāt |

bāṣpotkliṣṭadoṣastambhabhayāt |

api ca ||

Now, while the patient is seated evenly and comfortably, [the physician,] sitting down, should lift the upper eyelid with the left thumb and lead the collyrium below the black part [of the eye] from the inner canthus to the outer canthus—neither too little nor excessive, neither too thin nor too thick, neither dry nor coarse, neither fast nor delayed, not with a crooked gaze, without shaking, without friction, and without excessive pressure.
With powder, however, one should move back and forth;
otherwise, redness, lacrimation, corneal opacity, and the like will arise.
Then, in order for the collyrium to spread, without opening the eye, he should slowly move the eyeball inside.
In this way, it follows the eye.
He should move the eyelids slightly,
but he should not suddenly open, squeeze, or wash [the eyes],
for fear of arresting the doṣas agitated by the steam.
Moreover: