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This has been prov'd as to a Coal, by what I long since published in my Physico-Mechanical Experiments, where I relate, How quickly a Coal would be extinguish'd upon the withdrawing the Air from about it: And as to Shining Wood, the Experiments I lately sent you, make it needless for me to add any other proof of the requisiteness not only of Air, but of Air of such a thickness, to make its Light continue. How far this is applicable to Flame is not necessary here to determin; though, when I have the satisfaction of seeing you again, I may tell you something about that Question, which perhaps you do not expect.
3, Both Shining Wood and a Burning Coal, having hem deprived for a time of their light, by the withdrawing of the contiguous Air, may presently recover it by letting in fresh Air upon them.
The former part of this, particular Tryals have often shewn you to be true, when kindled Coals, that seem to be extinguisht in our exhausted Receivers, were presently reviv'd when the Air was restored to them: And the latter part is abundantly manifest by the Experiments, to which this Paper is an Appendance.
4. Both a Quick Coal and Shining Wood will be easily quench'd by Water and many other Liquors.
The truth of this, as to Coals, is too obvious to need a proof and therefore I shall confirm it only as to Wood. For which purpose you may be pleas'd to take the following Transcript of some of my Notes about Light.
I took a piece of shining Wood, and having wetted it with a little common Water in a clear Glass, it presently lost all its light*.*From hence you will easily gather the reason why, when I lately told you of the Trial I made with a piece of Shining Fish under Water in the unexhausted Receiver, I did not propose to have the like Trial made with Shining Wood and Water; but for this Liquor substituted Mercury.
The like Experiment I tried with strong Spirit of Salt, and also with weak Spirit of Sal Armoniack; but in both, the light did upon the Wood's imbibing of the Liquor presently disappear.
And lest you should think, that in the words Many other Liquors, I intended not to comprise any, that consist of soft and unctuous-parts, or that are highly inflamable, I shall sub-
