There was then four Drams and a half after 52 Distillations of a sharp, red, shining Powder, purging upwards and downwards: There remained 16 Ounces and 5 Drachms of Quicksilver; so 6½ Drachms were lost. This could not be help’d. Some part expires thro’ the Glew; something black, with a little Quicksilver, sticks to the Blotting-Paper every time the Mercury is dried. This is but very little at one time; but when the Work comes to be often repeated, it comes by Degrees to be a considerable part. The Powder produced was heavy, of a red shining Colour, very brittle, of a very sharp, metallic Taste, nauseous, penetrating, hardly to be taken out of the Mouth, disordering the Human Body very much, and for a long time, and disposing to Excretions. The Mercury which had been thus treated, appeared more fluid than common Mercury. COROLLARIES. 1. Quicksilver thus forced by Fire, is turned from a Fluid into Powder, in about the ¹⁄₂₈ part of its whole Weight. 2. From a Silver Brightness, like Looking-Glass, into a shining red Colour. 3. From very insipid Taste, into one very sharp, rough, metallic, and penetrating. 4. From very mild, into sharp, virulent, venomous, disordering the Body, and exciting Pains. 5. From volatile into more fixed; which is no longer volatile by the same Degree of Fire as it flew up with before. 6. As to its other part, it changes into more fluid, in other respects like what it was before. 7. When the Vessel is stopt close, a mechanic Motion, and a small Fire, give Quicksilver a black Colour; a greater Fire gives it a red Colour. EXPERIMENT V. _I was desirous to know what would happen to the Mercury, if it was still forced by a Fire requisite to Distillation._ _The Operation._ I took care to distill, as before, the 16 Ounces and 5 Drachms of Mercury remaining from the former Operation: I distill’d it so long, ’till there remained none in the Bottom. What was came over, being cleaned and dried, I always poured again into the same Retort. This Work I repeated 448 distinct times. Now this Mercury had been forced by Distillation compleatly 500 times: It had risen always more fluid and pure. The last time I heated the Fire more, but then the red Powder seem’d rather to be lessened than increased, perhaps being in part revived. _The Effect._ The Powder in the bottom of the Retort, weigh’d 1 Ounce, 5 Drams, and 21 Grains. The Mercury remaining after 500 Distillations, weighed 9 Ounces and 5 Drachms: But it happen’d, in so often distilling, that sometimes the Retorts broke, and so some of the Mercury got away, besides what was lost by so often cleaning and drying. COROLLARIES. 1. The Corollaries of the second and fourth Operations, are likewise true in this Operation. 2. The Mercury is very unchangeable in one part, 3. Yet continually changeable in the other part. 4. Out of the altered Form, perhaps it returns into its former Shape.