Of Medicines appropriated to the eyes.
Project Gutenberg EPUB3 edition
Culpeper, Nicholas
Take such medicines as are appropriated to the eyes under the name of (Ocular Medicines) I do it partly to avoid multiplicity of words, and partly to instruct my countrymen in the terms of art belonging to physic, (I would have called them [Ophthalmics] had not the word been troublesome to the reading, much more to the understanding of a countryman) as I even now called such medicines [Cephalics] as were appropriated to the brain.
Ocular medicines are two-fold, viz. such as are referred to the visive virtues, and such as are referred to the eyes themselves.
Such as strengthen the visive virtue or the optick nerves which convey it to the eyes (say Doctors) do it by an hidden virtue, into the reason which no man can dive, unless they should fetch it from the similitude of the substance: And yet they say a Goat’s liver conduces much to make one see in the night, and they give this reason, because Goats see as well in the night as in the day. Yet is there no affinity in temperature nor substance between the liver and the eyes: However Astrologers know well enough that all herbs, plants, &c. that are under the dominion of either sun or moon, and appropriated to the head, be they hot or cold they strengthen the visive virtue, as Eyebright, which is hot, Lunaria, or Moonwort which is cold.
As for what appertains to the constitution of the eyes themselves, seeing they are exact in sense, they will not endure the least inconvenience, therefore such medicines as are outwardly applied to them (for such medicines as strengthen the visive virtues are always given inwardly) let them neither hurt by their hardness nor gnawing quality, nor be so tough that they should stick to them. Therefore let ocular medicines be neither in powders nor ointments, because oil itself is offensive to the eyes, and how pleasing powders are to them, you may perceive yourself by just going into the dust.