Page:Philosophical Transactions - Volume 002.djvu/191

 of the Fish, we readmitted it, and upon its rushing in, perceived the Light to be as it were revived and encreased; those parts of the Fish that were scarce visible before, or shone but dimly, receiving presently their former splendour.

And not to leave unprosecuted the remaining part of the Experiment, which was to try, Whether it was the Kind of the Luminous Body, or only the greatness of the Bulk, and the vividness of Light, and, if I may so speak, the Tenacity of the substance it resided in; that made the difference between the Fish and the Wood; we put part of the Fish of another kind, that shone much more faintly than that hitherto spoken of, and but in some places; and by the withdrawing the Air, we made some of the luminous parts disappear, and the others so dim, as scarce to be discerned, and yet both the one and the other regained their former light upon the return of the Air.

And to pursue the Experiment a little further, we put in such a piece of the first Fish as though it were bright, was yet but thin, and not considerably great, and upon pumping out the Air, we found it, according to our expectation, quite eclipsed, though it recovered its Light upon the Air's re-entry.

I scarce doubt, but these Experiments will occasion among the Virtuosi several Queries and Conjectures, according to the differing Hypotheses ''and Inquisitions, to which men are inclined. And particularly 'tis probable, that some will make use of this Discourse to countenance their Opinion, That notwithstanding the Coldness (at least as to sense) of Fishes and other Animals, there may he in the Heart and Blood a Vital kind of Fire, which needs Air, as well as those Fires that are sensibly hot: Which may lessen the wonder, that Animals should not he able to live when robbed of Air. And if I had now time, I could possibly furnish you with some other Trials, that seem much to favour the Comparison, though as to the opinion it self of a Vital Flame, I shall not now tell you my thoughts about it. And though not only the Cartesians will perhaps draw an Argument from the past Phænomena in favour of their Theory of Light, but divers others will discourse upon them, and propose further Questions, and perhaps Enquiries suitable to their several Hypotheses; yet I shall content my self at present to have faithfully delivered the Historical part of these Apparences, without'' making