dissolve it as soon, and as violently as the more strong menstruum of melted Nitre.
Therefore twelfthly, it seems reasonable to think that there is no such thing as an Element of Fire that should attract or draw up the flame, or towards which the flame should endeavour to ascend out of a desire or appetite of uniting with that as its Homogeneal primitive and generating Element; but that that shining transient body which we call Flame, is nothing else but a mixture of Air, and volatil sulphureous parts of dissoluble or combustible bodies, which are acting upon each other whilst they ascend, that is, flame seems to be a mixture of Air, and the combustible volatil parts of any body, which parts the encompassing Air does dissolve or work upon, which action, as it does intend the heat of the aerial parts of the dissolvent, so does it thereby further rarifie those parts that are acting, or that are very neer them, whereby they growing much lighter then the heavie parts of that menstruum that are more remote, are thereby protruded and driven upward; and this may be easily observ'd also in dissolution made by any other menstruum, especially such as either create heat or bubbles. Now, this action of the menstruum, or Air, on the dissoluble parts, is made with such violence, or is such, that it imparts such a motion or pulse to the diaphanous parts of the Air, as I have elsewhere shewn is requisite to produce light.
This Hypothesis I have endeavoured to raise from an Infinite of Observations and Experiments, the process of which would be much too long to be here inserted, and will perhaps another time afford matter copious enough for a much larger Discourse, the Air being a Subject which (though all the world has hitherto liv'd and breath'd in, and been unconversant about) has yet been so little truly examin'd or explain'd, that a diligent enquirer will be able to find but very little information from what has been (till of late) written of it: But being once well understood, it will, I doubt not, inable a man to render an intelligible, nay probable, if not the true reason of all the Phænomena of Fire, which, as it has been found by Writers and Philosophers of all Ages a matter of no small difficulty, as may be sufficiently understood by their strange Hypotheses, and unintelligible Solutions of some few Phænomena of it; so will it prove a matter of no small concern and use in humane affairs, as I shall elsewhere endeavour to manifest when I come to shew the use of the Air in respiration, and for the preservation of the life, nay, for the conservation and restauration of the health and natural constitution of mankind as well as all other aereal animals, as also the uses of this principle or propriety of the Air in chymical, mechanical, and other operations. In this place I have onely time to hint an Hypothesis, which, if God permit me life and opportunity, I may elsewhere prosecute, improve and publish. In the mean time, before I finish this Discourse, I must not forget to acquaint the Reader, that having had the liberty granted me of making some trials on a piece of Lignum fossile shewn to the Royal Society, by the eminently Ingenious and Learned Physician, Doctor Ent, who receiv'd it for a Present from the famous Ingenioso Cavalliero de Pozzi, it being one of the fairest
