Chymistry was the Study of those Times, and Lectures were given in them at the Universities, as frequently as they are in Philosophy at present. It is for this Reason, I apprehend, that Shakespeare introduces Friar Lawrence, a Student in a Convent or Roman Catholic College, with several Kinds of Herbs in a Basket, the particular Virtues of which he seems perfectly to understand, and which he is going to extract from them, for physical Uses: Had Shakespeare lived in these Times, most likely he would have introduced him with a Quadrant, a Globe, or a Prism, or some other Philosophical Instrument. Now those who have not seen some little of Chymistry, have no Notion of the Wonders that are to be done by it; and these crafty Priests knew so well how to make Use of their Art to the best Advantage, that they could frighten a whole Village, whenever they had an Inclination to play their Pranks. Friar Bacon, who was perhaps the greatest Chymist in Europe, used to play so many Tricks, that he was thought by the whole Country, to deal with the Devil; and many Stories of him are now extant, to that Effect. One of the most common Pranks amongst these Gentry was this: They used to get one who could draw well, to take some Phosphorus (which is a Chymical Preparation from Urine) in his Pocket; having thus armed themselves, they perhaps would step into the first Alehouse where they saw a Light, and mix with the Company. He who was in Possession of the Phosphorus would get up and go to the Wall, under some Pretence or other, upon which he would draw what Picture came first into his Head, very likely the Picture of the Devil. Nothing is to be seen by Candle-Light, and it must be dark, before the Marks made by Phosphorus upon a Wall will appear like Fire. After sitting a little while, one of them would either introduce some Discourse about the Wickedness of the Times, or would tell some Story about Apparitions; in the middle of which another would run against the Candle, as if by Accident, and put it out. As soon as the Candle is out, another of them pretends to have found out this Figure upon the Wall, which will appear like Fire. You may guess the Surprize of the poor Country People, at seeing the Old Gentleman upon the Wall.--They all take to their Heels. In the mean Time, to improve their Ideas, another of the Confederates sets Fire to Brimstone, or some other stinking Combustible, and pops it against all their Noses, as they run out of Doors; and after these two powerful Sensations of seeing and smelling, it would be quite impossible, by any Arguments, to persuade any of the Company, that they had not actually seen the Prince of Darkness. By these and such like Arts, the Roman Catholic Priests so long kept this now well-delivered Country under their Subjection.