As is before shewed, take Urine well putrefied in a Tub, exposed to the Air for seven Weeks, all one as you do when you’re to make a Spirit of it; the Spirit being drawn, or rather the whole of it being evaporated to the consistance of Honey, in which lies the Fosperus; but the Art is somewhat difficult to get it from thence, in two cases, the one is in making choice of a proper Agent to be mixed therewith, and the other is the exact regiment of the Fire.
Take the Sap of Urine, as before ’tis said, or that of Dung and Urine putrified together, and incorporate it with Charcoal-dust, and put it into a German Retort, and lute on a Receiver, that is filled half full with Water, that when the Fosperus comes over, it may immediately drop into the Water and be preserved thereby.
Observe, That you are to begin with a very small Fire, but you are to increase it gradually into the highest degree that possibly can be made, and you’l see Flakes like Lightening.
Observations concerning it.
If you write upon the Palm of your Hand, or upon Paper with the said Gum, what ever you write will appear all on fire, and the Letters may be read a long time after; but you must have a great care, that you do it softly, and to put it into Water, as soon as you have done, for if it happen to fire ’twill burn the place most dreadfully.
Cut a little piece of the said Gum, and lay it upon Paper, and rub it on with the point of a Knife, and ’twill set the Paper on fire.
You will see Flashes like Lightening, somewhat like the flame of Brimstone, and somewhat of a purplish colour. If the Privy Parts be therewith rubb’d, they will be inflamed and burning for a good while after.