this--not only the admission of external air is prevented (of which we
have treated), but the spirit of bodies also is prevented from making
its escape, which is an internal operation. For any one operating on
natural bodies must be certain as to their quantity, and that nothing
has evaporated or escaped, since profound alterations take place in
bodies, when art prevents the loss or escape of any portion, while
nature prevents their annihilation. With regard to this circumstance,
a false idea has prevailed (which if true would make us despair of
preserving quantity without diminution), namely, that the spirit of
bodies, and air when rarefied by a great degree of heat, cannot be so
kept in by being inclosed in any vessel as not to escape by the small
pores. Men are led into this idea by the common experiments of a cup
inverted over water, with a candle or piece of lighted paper in it,
by which the water is drawn up, and of those cups which, when heated,
draw up the flesh. For they think that in each experiment the rarefied
air escapes, and that its quantity is therefore diminished, by which
means the water or flesh rises by the motion of connection. This is,
however, most incorrect. For the air is not diminished in quantity, but
contracted in dimensions,[161] nor does this motion of the rising of
the water begin till the flame is extinguished, or the air cooled, so
that physicians place cold sponges, moistened with water, on the cups,
in order to increase their attraction. There is, therefore, no reason
why men should fear much from the ready escape of air: for although it
be true that the most solid bodies have their pores, yet neither air,
nor spirit, readily suffers itself to be rarefied to such an extreme
degree; just as water will not escape by a small chink.
2. With regard to the second of the seven above-mentioned methods, we
must especially observe, that compression and similar violence have a
most powerful effect either in producing locomotion, and other motions
of the same nature, as may be observed in engines and projectiles, or
in destroying the organic body, and those qualities, which consist
entirely in motion (for all life, and every description of flame and
ignition are destroyed by compression, which also injures and deranges
every machine); or in destroying those qualities which consist in
position and a coarse difference of parts, as in colors; for the color
of a flower when whole, differs from that it presents when bruised, and
the same may be observed of whole and powdered amber; or in tastes,
for the taste of a pear before it is ripe, and of the same pear when
bruised and softened, is different, since it becomes perceptibly
more sweet. But such violence is of little avail in the more noble
transformations and changes of homogeneous bodies, for they do not,
by such means, acquire any constantly and permanently new state, but
one that is transitory, and always struggling to return to its former
habit and freedom. It would not, however, be useless to make some
more diligent experiments with regard to this; whether, for instance,
the condensation of a perfectly homogeneous body (such as air, water,
oil, and the like) or their rarefaction, when effected by violence,
can become permanent, fixed, and, as it were, so changed, as to become
a nature. This might at first be tried by simple perseverance, and
then by means of helps and harmonies. It might readily have been
attempted (if we had but thought of it), when we condensed water (as
was mentioned above), by hammering and compression, until it burst
out. For we ought to have left the flattened globe untouched for some
days, and then to have drawn off the water, in order to try whether it
would have immediately occupied the same dimensions as it did before
the condensation. If it had not done so, either immediately, or soon
afterward, the condensation would have appeared to have been rendered
constant; if not, it would have appeared that a restitution took place,
and that the condensation had been transitory. Something of the same
kind might have been tried with the glass eggs; the egg should have
been sealed up suddenly and firmly, after a complete exhaustion of
the air, and should have been allowed to remain so for some days, and
it might then have been tried whether, on opening the aperture, the
air would be drawn in with a hissing noise, or whether as much water
would be drawn into it when immersed, as would have been drawn into it
at first, if it had not continued sealed. For it is probable (or, at
least, worth making the experiment) that this might have happened, or
might happen, because perseverance has a similar effect upon bodies
which are a little less homogeneous. A stick bent together for some
time does not rebound, which is not owing to any loss of quantity in
the wood during the time, for the same would occur (after a larger
time) in a plate of steel, which does not evaporate. If the experiment
of simple perseverance should fail, the matter should not be given up,
but other means should be employed. For it would be no small advantage,
if bodies could be endued with fixed and constant natures by violence.
Air could then be converted into water by condensation, with other
similar effects; for man is more the master of violent motions than of
any other means.
3. The third of our seven methods is referred to that great practical
engine of nature, as well as of art, cold and heat. Here, man’s power
limps, as it were, with one leg. For we possess the heat of fire, which
is infinitely more powerful and intense than that of the sun (as it
reaches us), and that of animals. But we want cold,[162] except such
as we can obtain in winter, in caverns, or by surrounding objects
with snow and ice, which, perhaps, may be compared in degree with
the noontide heat of the sun in tropical countries, increased by the
reflection of mountains and walls. For this degree of heat and cold can
be borne for a short period only by animals, yet it is nothing compared
with the heat of a burning furnace, or the corresponding degree of
cold.[163] Everything with us has a tendency to become rarefied,
dry and wasted, and nothing to become condensed or soft, except
by mixtures, and, as it were, spurious methods. Instances of cold,
therefore, should be searched for most diligently, such as may be found
by exposing bodies upon buildings in a hard frost, in subterraneous
caverns, by surrounding bodies with snow and ice in deep places
excavated for that purpose, by letting bodies down into wells, by
burying bodies in quicksilver and metals, by immersing them in streams
which petrify wood, by burying them in the earth (which the Chinese
are reported to do with their china, masses of which, made for that
purpose, are said to remain in the ground for forty or fifty years, and
to be transmitted to their heirs as a sort of artificial mine) and the
like. The condensations which take place in nature, by means of cold,
should also be investigated, that by learning their causes, they may
be introduced into the arts; such as are observed in the exudation of
marble and stones, in the dew upon the panes of glass in a room toward
morning after a frosty night, in the formation and the gathering of
vapors under the earth into water, whence spring fountains and the like.
Besides the substances which are cold to the touch, there are others
which have also the effect of cold, and condense; they appear, however,
to act only upon the bodies of animals, and scarcely any further. Of
these we have many instances, in medicines and plasters. Some condense
the flesh and tangible parts, such as astringent and inspissating
medicines, others the spirits, such as soporifics. There are two modes
of condensing the spirits, by soporifics or provocatives to sleep;
the one by calming the motion, the other by expelling the spirit. The
violet, dried roses, lettuces, and other benign or mild remedies,
by their friendly and gently cooling vapors, invite the spirits to
unite, and restrain their violent and perturbed motion. Rose-water,
for instance, applied to the nostrils in fainting fits, causes the
resolved and relaxed spirits to recover themselves, and, as it were,
cherishes them. But opiates, and the like, banish the spirits by
their malignant and hostile quality. If they be applied, therefore,
externally, the spirits immediately quit the part and no longer readily
flow into it; but if they be taken internally, their vapor, mounting
to the head, expels, in all directions, the spirits contained in the
ventricles of the brain, and since these spirits retreat, but cannot
escape, they consequently meet and are condensed, and are sometimes
completely extinguished and suffocated; although the same opiates, when
taken in moderation, by a secondary accident (the condensation which
succeeds their union), strengthen the spirits, render them more robust,
and check their useless and inflammatory motion, by which means they
contribute not a little to the cure of diseases, and the prolongation
of life.
The preparations of bodies, also, for the reception of cold should not
be omitted, such as that water a little warmed is more easily frozen
than that which is quite cold, and the like.
Moreover, since nature supplies cold so sparingly, we must act like the
apothecaries, who, when they cannot obtain any simple ingredient, take
a succedaneum, or _quid pro quo_, as they term it, such as aloes for
xylobalsamum, cassia for cinnamon. In the same manner we should look
diligently about us, to ascertain whether there may be any substitutes
for cold, that is to say, in what other manner condensation can be
effected, which is the peculiar operation of cold. Such condensations
appear hitherto to be of four kinds only. 1. By simple compression,
which is of little avail toward permanent condensation, on account
of the elasticity of substances, but may still, however, be of some
assistance. 2. By the contraction of the coarser, after the escape
or departure of the finer parts of a given body; as is exemplified
in induration by fire, and the repeated heating and extinguishing of
metals, and the like. 3. By the cohesion of the most solid homogeneous
parts of a given body, which were previously separated, and mixed with
others less solid, as in the return of sublimated mercury to its simple
state, in which it occupies much less space than it did in powder, and
the same may be observed of the cleansing of all metals from their
dross. 4. By harmony, or the application of substances which condense
by some latent power. These harmonies are as yet but rarely observed,
at which we cannot be surprised, since there is little to hope for from
their investigation, unless the discovery of forms and confirmation
be attained. With regard to animal bodies, it is not to be questioned
that there are many internal and external medicines which condense
by harmony, as we have before observed, but this action is rare in
inanimate bodies. Written accounts, as well as report, have certainly
spoken of a tree in one of the Tercera or Canary Islands (for I do
not exactly recollect which) that drips perpetually, so as to supply
the inhabitants, in some degree, with water; and Paracelsus says that
the herb called _ros solis_ is filled with dew at noon, while the sun
gives out its greatest heat, and all other herbs around it are dry. We
treat both these accounts as fables; they would, however, if true, be
of the most important service, and most worthy of examination. As to
the honey-dew, resembling manna, which is found in May on the leaves
of the oak, we are of opinion that it is not condensed by any harmony
or peculiarity of the oak leaf, but that while it falls equally upon
other leaves it is retained and continues on those of the oak, because
their texture is closer, and not so porous as that of most of the other
leaves.[164]
With regard to heat, man possesses abundant means and power; but his
observation and inquiry are defective in some respects, and those of
the greatest importance, notwithstanding the boasting of quacks. For
the effects of intense heat are examined and observed, while those of
a more gentle degree of heat, being of the most frequent occurrence
in the paths of nature, are, on that very account, least known. We
see, therefore, the furnaces, which are most esteemed, employed in
increasing the spirits of bodies to a great extent, as in the strong
acids, and some chemical oils; while the tangible parts are hardened,
and, when the volatile part has escaped, become sometimes fixed; the
homogeneous parts are separated, and the heterogeneous incorporated and
agglomerated in a coarse lump; and (what is chiefly worthy of remark)
the junction of compound bodies, and the more delicate conformations
are destroyed and confounded. But the operation of a less violent heat
should be tried and investigated, by which more delicate mixtures and
regular conformations may be produced and elicited, according to the
example of nature, and in imitation of the effect of the sun, which we
have alluded to in the aphorism on the instances of alliance. For the
works of nature are carried on in much smaller portions, and in more
delicate and varied positions than those of fire, as we now employ
it. But man will then appear to have really augmented his power, when
the works of nature can be imitated in species, perfected in power,
and varied in quantity; to which should be added the acceleration in
point of time. Rust, for instance, is the result of a long process, but
_crocus martis_ is obtained immediately; and the same may be observed
of natural verdigris and ceruse. Crystal is formed slowly, while glass
is blown immediately: stones increase slowly, while bricks are baked
immediately, etc. In the meantime (with regard to our present subject)
every different species of heat should, with its peculiar effects, be
diligently collected and inquired into; that of the heavenly bodies,
whether their rays be direct, reflected, or refracted, or condensed by
a burning-glass; that of lightning, flame, and ignited charcoal; that
of fire of different materials, either open or confined, straitened or
overflowing, qualified by the different forms of the furnaces, excited
by the bellows, or quiescent, removed to a greater or less distance,
or passing through different media; moist heats, such as the _balneum
Mariæ_, and the dunghill; the external and internal heat of animals;
dry heats, such as the heat of ashes, lime, warm sand; in short, the
nature of every kind of heat, and its degrees.
We should, however, particularly attend to the investigation and
discovery of the effects and operations of heat, when made to approach
and retire by degrees, regularly, periodically, and by proper intervals
of space and time. For this systematical inequality is in truth the
daughter of heaven and mother of generation, nor can any great result
be expected from a vehement, precipitate, or desultory heat. For this
is not only most evident in vegetables, but in the wombs of animals
also there arises a great inequality of heat, from the motion, sleep,
food, and passions of the female. The same inequality prevails in
those subterraneous beds where metals and fossils are perpetually
forming, which renders yet more remarkable the ignorance of some of the
reformed alchemists, who imagined they could attain their object by the
equable heat of lamps, or the like, burning uniformly. Let this suffice
concerning the operation and effects of heat; nor is it time for us
to investigate them thoroughly before the forms and conformations
of bodies have been further examined and brought to light. When we
have determined upon our models, we may seek, apply, and arrange our
instruments.
4. The fourth mode of action is by continuance, the very steward and
almoner, as it were, of nature. We apply the term continuance to the
abandonment of a body to itself for an observable time, guarded and
protected in the meanwhile from all external force. For the internal
motion then commences to betray and exert itself when the external and
adventitious is removed. The effects of time, however, are far more
delicate than those of fire. Wine, for instance, cannot be clarified
by fire as it is by continuance. Nor are the ashes produced by
combustion so fine as the particles dissolved or wasted by the lapse
of ages. The incorporations and mixtures, which are hurried by fire,
are very inferior to those obtained by continuance; and the various
conformations assumed by bodies left to themselves, such as mouldiness,
etc., are put a stop to by fire or a strong heat. It is not, in the
meantime, unimportant to remark that there is a certain degree of
violence in the motion of bodies entirely confined; for the confinement
impedes the proper motion of the body. Continuance in an open vessel,
therefore, is useful for separations, and in one hermetically sealed
for mixtures, that in a vessel partly closed, but admitting the air,
for putrefaction. But instances of the operation and effect of
continuance must be collected diligently from every quarter.
5. The direction of motion (which is the fifth method of action) is
of no small use. We adopt this term, when speaking of a body which,
meeting with another, either arrests, repels, allows, or directs
its original motion. This is the case principally in the figure and
position of vessels. An upright cone, for instance, promotes the
condensation of vapor in alembics, but when reversed, as in inverted
vessels, it assists the refining of sugar. Sometimes a curved form,
or one alternately contracted and dilated, is required. Strainers may
be ranged under this head, where the opposed body opens a way for
one portion of another substance and impedes the rest. Nor is this
process or any other direction of motion carried on externally only,
but sometimes by one body within another. Thus, pebbles are thrown
into water to collect the muddy particles, and syrups are refined by
the white of an egg, which glues the grosser particles together so as
to facilitate their removal. Telesius, indeed, rashly and ignorantly
enough attributes the formation of animals to this cause, by means of
the channels and folds of the womb. He ought to have observed a similar
formation of the young in eggs which have no wrinkles or inequalities.
One may observe a real result of this direction of motion in casting
and modelling.
6. The effects produced by harmony and aversion (which is the
sixth method) are frequently buried in obscurity; for these occult
and specific properties (as they are termed), the sympathies and
antipathies, are for the most part but a corruption of philosophy. Nor
can we form any great expectation of the discovery of the harmony which
exists between natural objects, before that of their forms and simple
conformations, for it is nothing more than the symmetry between these
forms and conformations.
The greater and more universal species of harmony are not, however,
so wholly obscure, and with them, therefore, we must commence. The
first and principal distinction between them is this; that some bodies
differ considerably in the abundance and rarity of their substance, but
correspond in their conformation; others, on the contrary, correspond
in the former and differ in the latter. Thus the chemists have well
observed, that in their trial of first principles sulphur and mercury,
as it were, pervade the universe; their reasoning about salt, however,
is absurd, and merely introduced to comprise earthy dry fixed bodies.
In the other two, indeed, one of the most universal species of natural
harmony manifests itself. Thus there is a correspondence between
sulphur, oil, greasy exhalations, flame, and, perhaps, the substance of
the stars. On the other hand, there is a like correspondence between
mercury, water, aqueous vapor, air, and, perhaps, pure inter-sidereal
ether. Yet do these two quaternions, or great natural tribes (each
within its own limits), differ immensely in quantity and density of
substance, while they generally agree in conformation, as is manifest
in many instances. On the other hand, the metals agree in such quantity
and density (especially when compared with vegetables, etc.), but
differ in many respects in conformation. Animals and vegetables, in
like manner, vary in their almost infinite modes of conformation, but
range within very limited degrees of quantity and density of substance.
The next most general correspondence is that between individual bodies
and those which supply them by way of menstruum or support. Inquiry,
therefore, must be made as to the climate, soil, and depth at which
each metal is generated, and the same of gems, whether produced in
rocks or mines, also as to the soil in which particular trees, shrubs,
and herbs, mostly grow and, as it were, delight; and as to the best
species of manure, whether dung, chalk, sea sand, or ashes, etc., and
their different propriety and advantage according to the variety of
soils. So also the grafting and setting of trees and plants (as regards
the readiness of grafting one particular species on another) depends
very much upon harmony, and it would be amusing to try an experiment
I have lately heard of, in grafting forest trees (garden trees alone
having hitherto been adopted), by which means the leaves and fruit
are enlarged, and the trees produce more shade. The specific food of
animals again should be observed, as well as that which cannot be used.
Thus the carnivorous cannot be fed on herbs, for which reason the order
of feuilletans, the experiment having been made, has nearly vanished;
human nature being incapable of supporting their regimen, although the
human will has more power over the bodily frame than that of other
animals. The different kinds of putrefaction from which animals are
generated should be noted.
The harmony of principal bodies with those subordinate to them (such
indeed may be deemed those we have alluded to above) are sufficiently
manifest, to which may be added those that exist between different
bodies and their objects, and, since these latter are more apparent,
they may throw great light when well observed and diligently examined
upon those which are more latent.