The Philosophy of Natural Magic, by Henry Cornelius Agrippa, L. W. de Laurence ed. , at sacred-texts.com
Moreover, collyries and unguents, conveying the virtues of things natural and celestial to our spirit, can multiply, transmute, transfigure, and transform it accordingly, as also transpose those virtues which are in them into it; that so, it cannot act only upon its own body, but also upon that which is near it, and affect that by visible rays, charms, and by touching it with some like quality. For because our spirit is the subtile, pure, lucid, airy, and unctuous vapor of the blood, it is therefore fit to make collyries of the like vapors, which are more suitable to our spirit in substance, for then, by reason of their likeness, they do the more stir up, attract, and transform the spirit. The like virtues have certain ointments and other
confections. Hence by the touch sometimes sickness, poisonings, and love is induced; some things, as the hands or garments, being anointed. Also by kisses, some things being held in the mouth, love is induced; as in Virgil we read that Venus prays Cupid
Now the sight, because it perceives more purely and clearly than the other senses, and fastening in us the marks of things more acutely and deeply, doth most of all and before others, agree with the phantastic spirit, as is apparent in dreams, when things seen do more often present themselves to us than things heard, or any thing coming under the other senses. Therefore, when collyries or eye-waters transform visual spirits, that spirit doth easily affect the imagination, which indeed being affected with divers species and forms, transmits the same by the spirit unto the outward sense of sight; by which occasion there is caused in it a perception of such species and forms in that manner, as if it were moved by external objects, that there seem to be seen terrible images and spirits and such like. So there are made collyries, making us forthwith to see the images of spirits in the air or elsewhere; as I know how to make of the gall of a man, and the eyes of a black cat, and of some other things. The like is made also of the blood of a lapwing, of a bat, and a goat; and, they say, if a smooth, shining piece of steel be smeared over with the juice of mug-wort, and made to fume, it will make invoked spirits to be seen in it. So, also, there are some suffumigations, or unctions, which make men speak in their sleep, to walk, and to do those things which are done by men that are awake; and sometimes to do those things
which men that are awake cannot or dare not do. Some there are that make us to hear horrid or delectable sounds, and such like. And this is the cause why maniacal and melancholy men believe they see and hear those things without which their imagination doth only fancy within; hence they fear things not to be feared, and fall into wonderful and most false suspicions, and fly when none pursueth them; are also angry and contend, nobody being present, and fear where no fear is. Such like passions also can magical confections induce, by suffumigations, by collyries, by unguents, by potions, by poisons, by lamps and lights, by looking-glasses, by images, enchantments, charms, sounds and music. Also by divers rites, observations, ceremonies, religions and superstitions; all which shall be handled in their places. And not only by these kind of arts are passions, apparitions and images induced, but also things themselves, which are really changed and transfigured into divers forms, as the poet relates of Proteus, Periclimenus, Acheloas, and Merra, the daughter of Erisichthon. So, also, Circe changed the companions of Ulysses; and of old, in the sacrifices of Jupiter Lycæus, the men that tasted of the inwards of the sacrifices were turned into wolves which, Pliny saith, befell a certain man called Demarchus. The same opinion was Austin of, for, he saith, whilst he was in Italy, he heard of some women that by giving sorceries in cheese to travelers, turned them into working cattle, and when they had done such work as they would have them, turned them into men again; and that this befell a certain priest called Prestantius. The Scriptures themselves testify that Pharao's sorceries turned their rods into serpents and water into blood, and did other such like things.