Page:Philosophical Transactions

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practice, which, as to some of those designed Experiments, have been long denied me. But having at length got hither one of my little Engines, and having also procured, after much enquiry, a few small pieces of Shining Wood, I began on the day abovementioned to try with them an Experiment I found in my List. And though the main Experiment be but one, I intended to set down what occurr'd to me about it but as several Phænomena of it; yet finding it requisite to acquaint you with some Tryals that are not so properly Parts of it, I shall for distinction sake propose them as several Experiments; the Narratives whereof are taken, for the most part, verbatim out of the Notes I set down for my own use, when the things to be registred were freshly done. Which Advertisement I give you, both to excuse the carelessness of the Style, and to induce you not to distrust a Narrative that was made only to serve my Memory, not an Hypothesis.

Experiment I.

To try whether or no a piece of Shining Wood, being put into a Receiver of our Pneumatick Engine, would, upon the withdrawing and readmitting of the Air, suffer such changes, as I have often observed a Live Coal, placed there, to do; having at length procured a piece of such Wood, about the bigness of a Groat or less, that gave a vivid Light (for rotten Wood), we put it into a middle-sized Receiver, so as it was kept from touching the Cement; and the Pump being set a work, we observed not, during the five or six first Exsuctions of the Air, that the splendour of the included Wood was manifestly lessened (though it never was at all increased); but about the seventh suck, it seemed to grow a little more dim, and afterwards answered our expectation, by losing of its Light more and more, as the Air was still further pumped out; till at length about the tenth Exsuction (though by the removal of the Candles out of the Room, and by black Cloaths and Hats we made the place as dark as we could, yet) we could not perceive any Light at all to proceed from the Wood.

Experiment II.

Wherefore we let in the outward Air by degrees, and had the pleasure to lee the seemingly extinguisht Light revive so fat and perfectly, that it look to us all almost like a little flash of Lightning, and the splendour of the Wood seemed

rather

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