e 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 _Phaenomena_ 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 _Phaenomena_ of it;
so will it prove a matter of no small concern and use in humane affairs, as
I shall el