9. Whether Mercury shaken in a smaller Quantity, gives more of the black? (Powder) EXPERIMENT III. _The very black Powder (by EXPERIM. 2.) if it is forced out of a Glass Retort by a strong Fire, returns to pure Quicksilver._ _The Operation._ The 2 Drachms and 26 Grains of the black Powder (by _Operat. 2._) I heated by a strong Fire, and forced out of a pure Glass Retort, insomuch, that at last the Retort was red hot for 2 Hours. _The Effect._ There were in the Receiver 2 Drachms and 2 Grains of the purest Quicksilver, insipid and shining. There stuck to the Sides of the Glass, which being join’d to the Retort, is luted to a Receiver full of Water, a little Quicksilver here and there, which I could not entirely gather together. In the Bottom of the Retort was a fix’d Spot, small, very thin and fine, and but just visible. COROLLARIES. 1. Mercury, that has been 61 times distilled and shaken, and turned into the afore described Powder, returns by Fire alone into its first Form. 2. Of sharp and penetrating, it becomes very mild. 3. Of very black, it comes to resemble pure Looking-Glass, with a Silver Brightness. 4. Of a consistent Powder, it becomes very fluid. 5. In these three Operations it remains the same in itself; in the mean time it alters its Appearance under various Disguises. 6. The Taste and sharp Power are wonderfully changed in the Mercury, by Motion alone, by Fire alone. 7. In the mean time there arises, from these Operations, out of the Quicksilver, a small Quantity of fix’d Mercury. 8. The black (Spot) was no Dreg, or any Thing foreign, and so separated from the Mercury. SCHOLIUM. I exposed to a Fire of 180 Degrees, for several Months, some Quicksilver in Glass Conic Vessels, with flat Bottoms, that were stopt with a chemical inverted Phial: The Quicksilver became black, and gave a black Powder, in all respects alike; from which I learnt, that a Fire in this Degree, produced the same Effect in the Quicksilver as the shaking. EXPERIMENT IV. _Quicksilver is changed by simple Distillation._ _The Operation._ 18 Ounces of Quicksilver, Weight of _Amsterdam_, I forced by a Sand-Heat, out of a pure Glass Retort, into the Receiver that was filled with the purest Water, 4 Inches high from the Bottom: This I continued to do till there was no more running Mercury left in the Belly of the Vessel. I dried and cleaned the Mercury with clean dry blotting Paper, till it was perfectly dry, cleaned from any Dirt that might have fallen in, and from the Black which in distilling is raised every time with the Mercury as it distills: Then I poured this Mercury into another Retort, and forced it again as before. This I repeated in the same manner 52 times. In each Distillation there was produced in the Retort a red shining Powder. _The Effect._