That these kinds of Woods are duly numbred among such things as provoke Sweat, * 1.1 is plain from this, that sudorifical decoctions are made chiefly of them. The Hydro∣tick [or sweat-causing] virtue of them seems to consist in not onely a saline, but a sulphureous principle; for these Bod•…•… are abundantly filled with such kind of parti∣cles. Wherefore besides the common manner of preparing them, by infusion and boyling, thoir active principles of Salt and Sulphar are severally drawn forth by a chy∣mical resolution, and being reduced into peculiar concretions, that is to say, either a Spirit, an Oil, or a Rosin, make very fine, pleasant, and efficacious Diaphoreticks, or Sweating Medicins.
Take of the sawed dust of Guiacum wood lb ij. and distil it with a reverberating fire, or in an Oven of Sand with a strong heat, there will c•…•…me sorth a sharp, and somewhat acid liquor, and an oil that is yellow and black: separate the latter and rectifie the rest in a cucurbit, you will have a spirit that will be clear and sharp to the smell, as also an yellow and ponderous oil, which will settle in the bottom of the wat•…•…ry Liquor. The Dose of the Spirit is from ʒ ss. to ʒ j. ss. and of the Oil from vj. to xv. drops in a convenient vehicle.
Both Medicins are Diaphoretical, and are used with success in a Dropsie, the Scur∣vey, and the Pox. Without doubt the saline part of this Body, which is partly fluid, * 1.2 and partly volatile, together with the phlegm, makes up the Spirit so called; and the more pure sulphureous part, the yellow Oil, which besides that, through the quan∣tity of salt that sticks to it, is heavy and sinks: Yea some sulphureous particles stick fast to the acid sharp spirit or distilled liquor, in so much that it always stinks, and soon losing its clearness, degenerates to an yellow or a red colour. The black Oil con∣sists of a salt and sulphur that is thick, that is to say, mingled with a quantity of earth. In Guiacum the saline Element is, most part of it, elevated beyond fixedness, into a state of fluidity and volatileness; which is the reason that a Lie made of the ashes thereof, affordeth less Salt. It is quite otherwise in Tartar, whereof onely some of the saline parts are in a fluour, and a state of volatility, but most of them remain fixed.