When I found that the chief Persons of the Art agreed in these Principles for a long Time, I have endeavour’d to learn by Experience, by what Artifice a pure unmix’d Mercury might be obtained? Whether it cou’d be extracted out of Metals? What is that other Part of the Metal that is apt to force under its Yoak the free Quicksilver, or Mercury? I am glad to give an Account of what I have discovered; not that I pretend to teach the Art, which I am as far from as any one; but I will faithfully relate some laborious Experiments, and which are so very certain, that they may justly pass for true. Others will not need to repeat them, but may safely make use of these as true upon Occasion. And a diligent Artist, by assuming (or supposing) these Experiments, may apply his Mind farther to others, in order to promote the Study of Chemistry the more. It were to be wish’d, that every Man directed his private Labours to the public Good. Let the first Experiment be this: EXPERIMENT I. _Pure Quicksilver contain’d in a dry Glass Vessel that is very clean, being agitated only by a mechanical Shaking or Concussion, gives a soft, black, and very fine Powder._ _The Operation._ Having bought 16 Ounces of Quicksilver of the Company at _Amsterdam_, I strain’d it thro’ a Leather Bag; there remain’d no Dregs: I pounded it a long while with fair Water: The Quicksilver remained pure after pounding: It was then a long time pounded with Sea-Salt, but the Colour of the Salt was not fouled: after having poured Water to this Salt, and to the Mercury, the pounding was repeated; but neither did this change the Colour. In all this Work there appeared nothing black, nothing foreign or foul. Then the Quicksilver was washed and dried, and was bright. I poured it into a clean dry Glass Bottle, made of the dark-green _German_ Glass. At the same Time I plac’d it in a Sand Furnace, with a Fire that almost made the Mercury rise; and to be sure that all the Water was forced out, which is often secretly present in the Mercury, I kept it thus for three Days: Then having thrust a clean dry strong Cork into the Mouth of the Vessel whilst it was yet warm, I fasten’d it up as close as possible. The Head of the Bottle thus closed with a Cork, I dipt into a liquid Cement of Pitch, Rosin, Tallow, and Brimstone, and covered it over with a Linnen Cloth, which I tied fast with Packthread. When the Glass was thus made ready, I put it in a small Wooden Box, which was so fitted to the Bottle, that it touched the Sides of it; and the empty Spaces between the Bottle and the Box, were well filled with Bran. Then I put on a Cover, with a Hole bored in the Middle, for the Top of the Neck of the Bottle to stand a little out. The Glass was immoveable in the Box; and it being thus prepared, I had it fastened to the Hammering Block of a Fulling-Mill, which always moves Night and Day when there is any Wind. Being thus fixed, it was rais’d up and let down by a perpendicular Motion, from the