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.
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.