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either to my Humour or my Custom.

Now though I might present you many things against the Vulgar Chymical
Opinion of the three Principles, and the Experiments wont to be
alledg'd as Demonstrations of it, yet those I shall at present offer
you may be conveniently enough comprehended in four Capital
Considerations; touching all which I shall only premise this in
general, That since it is not my present Task so much to assert an
_Hypothesis_ of my own, as to give an Account wherefore I suspect the
Truth of that of the Chymists, it ought not to be expected that all my
Objections should be of the most cogent sort, since it is reason
enough to Doubt of a propos'd Opinion, that there appears no cogent
Reason for it.

To come then to the Objections themselves; I consider in the first
place, That notwithstanding what common Chymists have prov'd or
taught, it may reasonably enough be Doubted, how far, and in what
sence, Fire ought to be esteem'd the genuine and universal Instrument
of analyzing mixt Bodies.

This Doubt, you may remember, was formerly mention'd, but so
transiently discours'd of, that it will now be fit to insist upon it;
And manifest that it was not so inconsiderately propos'd as our
Adversaries then imagin'd.

But, before I enter any farther into this Disquisition, I cannot but
here take notice, that it were to be wish'd, our Chymists had clearly
inform'd us what kinde of Division of Bodies by Fire must determine
the number of the Elements: For it is nothing near so easy as many
seem to think, to determine distinctly the Effects of Heat, as I could
easily manifest, if I had leasure to shew you how much the Operations
of Fire may be diversify'd by Circumstances. But not wholly to pass by
a matter of this Importance, I will first take notice to you, that
_Guajacum_ (for Instance) burnt with an open Fire in a Chimney, is
sequestred into Ashes and Soot, whereas the same Wood distill'd in a
Retort does yield far other Heterogeneities, (to use the _Helmontian_
expression) and is resolv'd into Oyl, Spirit, Vinager, Water and
Charcoal; the last of which to be reduc'd into Ashes, requires the
being farther calcin'd then it can be in a close Vessel: Besides
having kindled Amber, and held a clean Silver Spoon, or some other
Concave and smooth Vessel over the Smoak of its Flame, I observ'd the
Soot into which that Fume condens'd, to be very differing from any
thing that I had observ'd to proceed from the steam of Amber purposely
(for that is not usual) distilled _per se_ in close Vessels. Thus
having, for Tryals sake, kindled Camphire, and catcht the Smoak that
copiously ascended out of the Flame, it condens'd into a Black and
unctuous Soot, which would not have been guess'd by the Smell or other
Properties to have proceeded from Camphire: whereas having (as I shall
otherwhere more fully declare) expos'd a quantity of that Fugitive
Concrete to a gentle heat in a close Glass-Vessel, it sublim'd up
without seeming to have lost any thing of its whiteness, or its
Nature, both which it retain'd, though afterwards I so encreased the
Fire as to bring it to Fusion. And, besides Camphire, there are divers
other Bodies (that I elsewhere name) in which the heat in close
Vessels is not wont to make any separation of Heterogeneities, but
only a comminution of Parts, those that rise first being Homogeneal
with the others, though subdivided into smaller Particles: whence
Sublimations have been stiled, _The Pestles of the Chymists_. But not
here to mention what I elsewhere take notice of, concerning common
Brimstone once or twice sublim'd, that expos'd to a moderate Fire in
Subliming-Pots, it rises all into dry, and almost tastless, Flowers;
Whereas being expos'd to a naked Fire it affords store of a Saline and
Fretting Liquor: Not to mention this, I say, I will further observe to
you, that as it is considerable in the _Analysis_ of mixt Bodies,
whether the Fire act on them when they are expos'd to the open Air, or
shut up in close Vessels, so is the degree of Fire by which the
_Analysis_ is attempted of no small moment. For a milde _Balneum_ will
sever unfermented Blood (for Instance) but into Phlegme and _Caput
mortuum_, the later whereof (which I have sometimes had) hard,
brittle, and of divers Colours, (transparent almost like
Tortoise-shell) press'd by a good Fire in a Retort yields a Spirit, an
Oyl or two, and a volatile Salt, besides a [Errata: another] _Caput
mortuum_. It may be also pertinent to our present Designe, to take
notice of what happens in the making and distilling of Sope; for by
one degree of Fire the Salt, the Water and the Oyl or Grease, whereof
that factitious Concrete is made up, being boyl'd up together are
easily brought to mingle and incorporate into one Mass; but by another
and further degree of Heat the same Mass may be again divided into an
oleagenous, an aqueous, a Saline, and an Earthy part. And so we may
observe that impure Silver and Lead being expos'd together to a
moderate Fire, will thereby be colliquated into one Mass, and mingle
_per minima_, as they speak, whereas a much vehementer Fire will drive
or carry off the baser Metals (I mean the Lead, and the Copper or
other Alloy) from the Silver, though not, for ought appears, separate
them from one another. Besides, when a Vegetable abounding in fixt
Salt is analyz'd by a naked Fire, as one degree of Heat will reduce it
into Ashes, (as the Chymists themselves teach us) so, by only a
further degree of Fire, those Ashes may be vitrified and turn'd into
Glass. I will not stay to examine how far a meere Chymist might on
this occasion demand, If it be lawful for an _Aristotelian_ to make
Ashes, (which he mistakes for meere Earth) pass for an Element,
because by one degree of Fire it may be produc'd, why a Chymist may
not upon the like Principle argue, that Glass is one of the Elements
of many Bodies, because that also may be obtain'd from them, barely by
the Fire? I will not, I say, lose time to examine this, but observe,
that by a Method of applying the Fire, such similar Bodies may be
obtain'd from a Concrete, as Chymists have not been able to separate;
either by barely burning it in an open Fire, or by barely distilling
it in close Vessels. For to me it seems very considerable, and I
wonder that men have taken so little notice of it, that I have not by
any of the common wayes of Distillation in close Vessels, seen any
separation made of such a volatile Salt as is afforded us by Wood,
when that is first by an open Fire divided into Ashes and Soot, and
that Soot is afterwards plac'd in a strong Retort, and compell'd by an
urgent Fire to part with its Spirit, Oyl and Salt; for though I dare
not peremptorily deny, that in the Liquors of _Guajacum_ and other
Woods distill'd in Retorts after the common manner, there may be
Saline parts, which by reason of the Analogy may pretend to the name
of some kinde of volatile Salts; yet questionless there is a great
disparity betwixt such Salts and that which we have sometimes obtain'd
upon the first Distillation of Soot (though for the most part it has
not been separated from the first or second Rectification, and
sometimes not till the third) For we could never yet see separated
from Woods analyz'd only the vulgar way in close vessels any volatile
Salt in a dry and Saline form, as that of Soot, which we have often
had very Crystalline and Geometrically figur'd. And then, whereas the
Saline parts of the Spirits of _Guajacum_, &c. appear upon
distillation sluggish enough, the Salt of Soot seems to be one of the
most volatile Bodies in all Nature; and if it be well made will
readily ascend with the milde heat of a Furnace, warm'd only by the
single Wieck of a Lamp, to the top of the highest Glass Vessels that
are commonly made use of for Distillation: and besides all this, the
taste and smell of the Salt of Soot are exceeding differing from those
of the Spirits of _Guajacum_, &c. and the former not only smells and
tastes much less like a vegetable Salt, than like that of Harts-horn,
and other Animal Concretes; but in divers other Properties seems more
of Kinne to the Family of Animals, than to that of vegetable Salts, as
I may elsewhere (God permitting) have an occasion more particularly to
declare. I might likewise by some other Examples manifest, That the
Chymists, to have dealt clearly, ought to have more explicitly and
particularly declar'd by what Degree of Fire, and in what manner of
Application of it, they would have us Judge a Division made by the
Fire to be a true _Analysis_ into their Principles, and the
Productions of it to deserve the name of Elementary Bodies. But it is
time that I proceed to mention the particular Reasons that incline me
to Doubt, whether the Fire be the true and universal Analyzer of mixt
Bodies; of which Reasons what has been already objected may pass for

In the next place I observe, That there are some mixt Bodies from
which it has not been yet made appear, that any degree of Fire can
separate either Salt or Sulphur or Mercury, much less all the Three.
The most obvious Instance of this Truth is Gold, which is a Body so
fix'd, and wherein the Elementary Ingredients (if it have any) are so
firmly united to each other, that we finde not in the operations
wherein Gold is expos'd to the Fire, how violent soever, that it does
discernably so much as lose of its fixednesse or weight, so far is it
from being dissipated into those Principles, whereof one at least is
acknowledged to be Fugitive enough; and so justly did the Spagyricall
Poet somewhere exclaim,

_Cuncta adeo miris illic compagibus harent._

And I must not omit on this occasion to mention to you, _Eleutherius_,
the memorable Experiment that I remember I met with in _Gasto
Claveus_,[2] who, though a Lawyer by Profession, seems to have had no
small Curiosity and Experience in Chymical affairs: He relates then,
that having put into one small Earthen Vessel an Ounce of the most
pure Gold, and into another the like weight of pure Silver, he plac'd
them both in that part of a Glass-house Furnace wherein the Workmen
keep their Metal, (as our English Artificers call their Liquid Glass)
continually melted, and that having there kept both the Gold and the
Silver in constant Fusion for two Moneths together, he afterwards took
them out of the Furnace and the Vessels, and weighing both of them
again, found that the Silver had not lost above a 12th part of its
weight, but the Gold had not of his lost any thing at all. And though
our Author endeavours to give us of this a Scholastick Reason, which I
suppose you would be as little satisfied with, as I was when I read
it; yet for the matter of Fact, which will serve our present turne, he
assures us, that though it be strange, yet Experience it self taught
it him to be most true.

[Footnote 2: _Gasto Claveus_ Apolog. Argur. & Chrysopera.]

And though there be not perhaps any other Body to be found so
perfectly fix'd as Gold, yet there are divers others so fix'd or
compos'd, at least of so strictly united parts, that I have not yet
observ'd the Fire to separate from them any one of the Chymists
Principles. I need not tell you what Complaints the more Candid and
Judicious of the Chymists themselves are wont to make of those
Boasters that confidently pretend, that they have extracted the Salt
or Sulphur of Quicksilver, when they have disguis'd it by Additaments,
wherewith it resembles the Concretes whose Names are given it;
whereas by a skilful and rigid _Examen_, it may be easily enough
stript of its Disguises, and made to appear again in the pristine form
of running Mercury. The pretended Salts and Sulphurs being so far from
being Elementary parts extracted out of the Bodie of Mercurie, that
they are rather (to borrow a terme of the Grammarians) De-compound
Bodies, made up of the whole Metal and the _Menstruum_ or other
Additaments imploy'd to disguise it. And as for Silver, I never could
see any degree of Fire make it part with any of its three Principles.
And though the Experiment lately mentioned from _Claveus_ may beget a
Suspition that Silver may be dissipated by Fire, provided it be
extreamly violent and very lasting: yet it will not necessarily
follow, that because the Fire was able at length to make the Silver
lose a little of its weight, it was therefore able to dissipate it
into its Principles. For first I might alledge that I have observ'd
little Grains of Silver to lie hid in the small Cavities (perhaps
glas'd over by a vitrifying heat) in Crucibles, wherein Silver has
been long kept in Fusion, whence some Goldsmiths of my Acquaintance
make a Benefit by grinding such Crucibles to powder, to recover out of
them the latent particles of Silver. And hence I might argue, that
perhaps _Claveus_ was mistaken, and imagin'd that Silver to have been
driven away by the Fire, that indeed lay in minute parts hid in his
Crucible, in whose pores so small a quantity as he mist of so
ponderous a Bodie might very well lie conceal'd.

But Secondly, admitting that some parts of the Silver were driven away
by the violence of the Fire, what proof is there that it was either
the Salt, the Sulphur, or the Mercury of the Metal, and not rather a
part of it homogeneous to what remain'd? For besides, that the Silver
that was left seem'd not sensibly alter'd, which probably would have
appear'd, had so much of any one of its Principles been separated from
it: We finde in other Mineral Bodies of a less permanent nature than
Silver, that the Fire may divide them into such minute parts, as to be
able to carry them away with its self, without at all destroying their
Nature. Thus we see that in the refining of Silver, the Lead that is
mix'd with it (to carry away the Copper or other ignoble Mineral that
embases the Silver) will, if it be let alone, in time evaporate away
upon the Test; but if (as is most usual amongst those that refine
great quantities of Metals together) the Lead be blown off from the
Silver by Bellowes, that which would else have gone away in the Form
of unheeded steams, will in great part be collected not far from the
Silver, in the Form of a darkish Powder or Calx, which, because it is
blown off from Silver, they call Litharge of Silver. And thus
_Agricola_[3] in divers places informs us, when Copper, or the Oare of
it is colliquated by the violence of the Fire with _Cadmia_, the
Sparks that in great multitudes do fly upwards do, some of them, stick
to the vaulted Roofs of the Furnaces, in the form of little and (for
the most part) White Bubbles, which therefore the Greeks, and, in
Imitation of them, our Drugsters call _Pompholix_: and others more
heavy partly adhere to the sides of the Furnace, and partly
(especially if the Covers be not kept upon the Pots) fall to the
Ground, and by reason of their Ashy Colour as well as Weight were
called by the same Greeks [Greek: spodos], which, I need not tell you,
in their Language signifies Ashes. I might add, that I have not found
that from Venetian Talck (I say Venetian, because I have found other
kinds of that Mineral more open) from the _Lapis Ossifragus_, (which
the Shops call _Ostiocolla_) from _Muscovia_ Glass, from pure and
Fusible Sand, to mention now no other Concretes; those of my
Acquaintance that have try'd have been able by the Fire to separate
any one of the Hypostatical Principles, which you will the less
scruple to believe, if you consider that Glass may be made by the bare
Colliquation of the Salt and Earth remaining in the Ashes of a burnt
Plant, and that yet common Glass, once made, does so far resist the
violence of the Fire, that most Chymists think it a Body more
undestroyable then Gold it self. For if the Artificer can so firmly
unite such comparative gross Particles as those of Earth and Salt that
make up common Ashes, into a Body indissoluble by Fire; why may not
Nature associate in divers Bodies the more minute Elementary
Corpuscles she has at hand too firmly to let them be separable by the
Fire? And on this Occasion, _Eleutherius_, give me leave to mention to
you two or three sleight Experiments, which will, I hope, be found
more pertinent to our present Discourse, than at first perhaps they
will appear. The first is, that, having (for Tryals sake) put a
quantity of that Fugitive Concrete, Camphire, into a Glass Vessel, and
plac'd it in a gentle Heat, I found it (not leaving behinde, according
to my Estimate, not so much as one Grain) to sublime to the Top of the
Vessel into Flowers: which in Whiteness, Smell, &c. seem'd not to
differ from the Camphire it self. Another Experiment is that of
_Helmont_, who in several places affirms, That a Coal kept in a Glass
exactly clos'd will never be calcin'd to Ashes, though kept never so
long in a strong Fire. To countenance which I shall tell you this
Tryal of my own, That having sometimes distilled some Woods, as
particularly Box, whilst our _Caput mortuum_ remain'd in the Retort,
it continued black like Charcoal, though the Retort were Earthen, and
kept red-hot in a vehement Fire; but as soon as ever it was brought
out of the candent Vessel into the open Air, the burning Coals did
hastily degenerate or fall asunder, without the Assistance of any new
Calcination, into pure white Ashes. And to these two I shall add but
this obvious and known Observation, that common Sulphur (if it be pure
and freed from its Vinager) being leasurely sublim'd in close Vessels,
rises into dry Flowers, which may be presently melted into a Bodie of
the same Nature with that which afforded them. Though if Brimstone be
burnt in the open Air it gives, you know, a penetrating Fume, which
being caught in a Glass-Bell condenses into that acid Liquor called
Oyl of Sulphur _per Campanam_. The use I would make of these
Experiments collated with what I lately told you out of _Agricola_ is
this, That even among the Bodies that are not fixt, there are divers
of such a Texture, that it will be hard to make it appear, how the
Fire, as Chymists are wont to imploy it, can resolve them into
Elementary Substances. For some Bodies being of such a Texture that
the Fire can drive them into the cooler and less hot part of the
Vessels wherein they are included, and if need be, remove them from
place to place to fly the greatest heat, more easily than it can
divorce their Elements (especially without the Assistance of the Air)
we see that our Chymists cannot Analyze them in close Vessels, and of
other compound Bodies the open Fire can as little separate the
Elements. For what can a naked Fire do to Analyze a mixt Bodie, if its
component Principles be so minute, and so strictly united, that the
Corpuscles of it need less heat to carry them up, than is requisite to
divide them into their Principles. So that of some Bodies the Fire
cannot in close Vessels make any _Analysis_ at all, and others will in
the open Air fly away in the Forms of Flowers or Liquors, before the
Heat can prove able to divide them into their Principles. And this may
hold, whether the various similar parts of a Concrete be combin'd by
Nature or by Art; For in factitious _Sal Armoniack_ we finde the
common and the Urinous Salts so well mingled, that both in the open
Fire, and in subliming Vessels they rise together as one Salt, which
seems in such Vessels irresoluble by Fire alone. For I can shew you
_Sal Armoniack_ which after the ninth Sublimation does still retain
its compounded Nature. And indeed I scarce know any one Mineral, from
which by Fire alone Chymists are wont to sever any Substance simple
enough to deserve the name of an Element or Principle. For though out
of native Cinnaber they distill Quicksilver, and though from many of
those Stones that the Ancients called _Pyrites_ they sublime
Brimstone, yet both that Quicksilver and this Sulphur being very often
the same with the common Minerals that are sold in the Shops under
those names, are themselves too much compounded Bodies to pass for the
Elements of such. And thus much, _Eleutherius_, for the Second
Argument that belongs to my First Consideration; the others I shall
the lesse insist on, because I have dwelt so long upon this.

[Footnote 3: _Agricola_ de Natura Fossil. Lib. 9. Cap. 11. & 12.]

Proceed we then in the next place to consider, That there are divers
Separations to be made by other means, which either cannot at all, or
else cannot so well be made by the Fire alone. When Gold and Silver
are melted into one Mass, it would lay a great Obligation upon
Refiners and Goldsmiths to teach them the Art of separating them by
the Fire, without the trouble and charge they are fain to be at to
sever them. Whereas they may be very easily parted by the Affusion of
Spirit of Nitre or _Aqua fortis_ (which the French therefore call _Eau
de Depart_:) so likewise the Metalline part of Vitriol will not be so
easily and conveniently separated from the Saline part even by a
violent Fire, as by the Affusion of certain Alkalizate Salts in a
liquid Form upon the Solution of Vitriol made in common water. For
thereby the acid Salt of the Vitriol, leaving the Copper it had
corroded to joyn with the added Salts, the Metalline part will be
precipitated to the bottom almost like Mud. And that I may not give
Instances only in De-compound Bodies, I will add a not useless one of
another kinde. Not only Chymists have not been able (for ought is
vulgarly known) by Fire alone to separate true Sulphur from Antimony;
but though you may finde in their Books many plausible Processes of
Extracting it, yet he that shall make as many fruitlesse Tryals as I
have done to obtain it by, most of them will, I suppose, be easily
perswaded, that the Productions of such Processes are Antimonial
Sulphurs rather in Name than Nature. But though Antimony sublim'd by
its self is reduc'd but to a volatile Powder, or Antimonial Flowers,
of a compounded Nature like the Mineral that affords them: yet I
remember that some years ago I sublim'd out of Antimony a Sulphur, and
that in greater plenty then ever I saw obtain'd from that Mineral, by
a Method which I shall therefore acquaint you with, because Chymists
seem not to have taken notice of what Importance such Experiments may
be in the Indagation of the Nature, and especially of the Number of
the Elements. Having then purposely for Tryals sake digested eight
Ounces of good and well powder'd Antimony with twelve Ounces of Oyl of
Vitriol in a well stopt Glas-Vessel for about six or seven Weeks; and
having caus'd the Mass (grown hard and brittle) to be distill'd in a
Retort plac'd in Sand, with a strong Fire; we found the Antimony to be
so opened, or alter'd by the _Menstruum_ wherewith it had been
digested, That whereas crude Antimony, forc'd up by the Fire, arises
only in Flowers, our Antimony thus handled afforded us partly in the
Receiver, and partly in the Neck and at the Top of the Retort, about
an Ounce of Sulphur, yellow and brittle like common Brimstone, and of
so Sulphureous a smell, that upon the unluting the Vessels it infected
the Room with a scarce supportable stink. And this Sulphur, besides
the Colour and Smell, had the perfect Inflamability of common
Brimstone, and would immediately kindle (at the Flame of a Candle) and
burn blew like it. And though it seem'd that the long digestion
wherein our Antimony and _Menstruum_ were detain'd, did conduce to the
better unlocking of the Mineral, yet if you have not the leasure to
make so long a Digestion, you may by incorporating with powder'd
Antimony a convenient Quantity of Oyl of Vitriol, and committing them
immediately to Distillation, obtain a little Sulphur like unto the
common one, and more combustible than perhaps you will at first take
notice of. For I have observ'd, that though (after its being first
kindled) the Flame would sometimes go out too soon of its self, if the
same Lump of Sulphur were held again to the Flame of a Candle, it
would be rekindled and burn a pretty while, not only after the
second, but after the third or fourth accension. You, to whom I think
I shewed my way of discovering something of Sulphureous in Oyl of
Vitriol, may perchance suspect, _Eleutherius_, either that this
Substance was some Venereal Sulphur that lay hid in that Liquor, and
was by this operation only reduc'd into a manifest Body; or else that
it was a compound of the unctuous parts of the Antimony, and the
Saline ones of the Vitriol, in regard that (as _Gunther_[4] informs
us) divers learned men would have Sulphur to be nothing but a mixture
made in the Bowels of the Earth of Vitriolate Spirits and a certain
combustible Substance. But the Quantity of Sulphur we obtain'd by

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