EXPER. XI.
To confirm this Experiment by a notable variation; we took finely powder'd Sal Armoniac, and filings or scales of Steel, and when they were very diligently mixt (for that Circumstance ought to be observ'd) we caus'd them to be gradually sublim'd in a glass vessel, giving a smart fire towards the latter end. By this Operation so little of the mixture ascended, that, as we desired, far the greatest part of the Sal Armoniac staid at the bottom with the metal; then taking out the Caput mortuum, I gave it time throughly to cool, but in a Glass well stopt, that it might not imbibe the moisture of the Air, (as it is very apt to do.) And lastly, though the Filings of Steel, as well as the Sal Armoniac, were bodies actually cold, and so might be thought likely to increase, notcheck,
