The Operation.
I suspecting that something of a foreign Nature to it might remain in the Quicksilver, and be separated from it, by Motion, under the Form of that Powder, I brought over all the Mercury in a Glass Retort with a Sand-Heat. When it was all over, I pour’d it again into the same Retort, and forc’d it by Fire, as before. This Method I repeated 60 times. The Mercury was thus distilled 61 times. In the Bottom of the Vessel there were five Drachms of Red Powder; of which hereafter. But this Mercury was very fluid and shining. I got 2 Ounces of this Mercury to be shaken by a Fulling-Mill in the same Manner, and by the same Operation, and for the same Space of Time as in the first Operation.
The Effect.
The Weight was the same: There was a Powder made, soft, black, of a sharp metallic Taste, like Copper or Brass, to the Quantity of 2 Drachms and 26 Grains: So it was above an eighth Part; whereas of the Mercury, as they sell it, scarce ¹⁄₁₂₈ Part was turn’d into Powder by the same Operations; that is, by the shaking of the Mill.
Corollaries.
1. The Mercury, which after being distilled 61 times, yet remained very tasteless and insipid, acquires a metallic Taste.
2. From being very mild, grows sharp and penetrating.
3. From having a bright Silver Colour, and shining like a Looking-Glass, becomes very black.
4. From being more fluid than it was naturally, comes to a consistent Powder.
5. Tho’ forced by a long and strong Fire, so often repeated, the Mercury still retains this Property (of Fluidity).