1st of _March_, 1732. _N. S._ to the 13ᵗʰ of _November_ of the same Year. _The Effect._ The Bottle being opened, there was the same Weight of Mercury, which was covered on all Sides with a very soft, black, copious and fine Powder. I squeez’d it thro’ a clean Leather Bag; the liquid and pure Mercury pass’d thro’. The Powder remained in the Bag of a sharp metallic Taste, somewhat resembling the Taste of Copper or Brass. COROLLARIES. 1. Quicksilver, in itself very insipid, by meer shaking, acquires a metallic Taste of Copper. 2. From being very mild, it becomes sharp and penetrating. 3. From a very bright Silver Colour, it turns very black. 4. From a Fluid, it becomes Solid in the Form of Powder. 5. It may therefore be concealed under the Appearance of such a Powder, and deceive the Ignorant. EXPERIMENT II. _Quicksilver exceedingly well purified, and treated as aforesaid (EXPER. 1.) gives the same Powder in much greater Plenty._ _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). 6. Which therefore does not depend on any Feces or Dregs foreign to the Mercury, and that may be separated from it by Fire. 7. The Matter which, after the Distillation of the Mercury, remain’d in the Bottom of the Retort, red, shining, and sharp, is no more like the black Powder proceeding from the Shaking, than that Part is of the Mercury, which remained volatile. 8. Mercury is changed by Fire and Shaking; by Fire into red, by Shaking into black: Therefore Mercury changes Colour.