The works of Francis Bacon, lord chancellor of England.

406 NOVUM ORGANUM. Boore II.
mals from putrefaction; for it would not be so the source of flame seems to be oil and fat; that
humane to inquire into perfect and terrestrial ani- of air, water, and watery substances; for flame
mals, by cutting the fetus from the womb; but increases over the exhalation of oil, and air over
opportunities may perhaps be offered of abortions, that of water. One must, therefore, consider the
animals killed in hunting, and the like. Na- mixture of oil and water, which is manifest to
ture, therefore, must, as it were, be watched, as the senses, since that of air and flame in general
being more easily observed by night than by day; escapes the senses. But oil and water mix very
for contemplations of this kind may be considered imperfectly by composition, or stirring, whilst
as carried on by night, from the minuteness and they are exactly and nicely mixed in herbs, blood,
perpetual burning of our watch-light. The same and the parts of animals. Somnething similar,
must be attempted with inanimate objects, which therefore, may take place in the mixture of flame
we have ourselves done by inquiring into the and air in spirituous substances, not bearing mixopening of liquids by fire. For the mode in ture very well by simple collision, whilst they
which water expands is different from that ob- appear, however, to be well mixed in the spirits
served in wine, vinegar, or verjuice, and very of plants and animals.
different again from that observed in milk and Again, if the inquiry do not relate to perfect
oil, and the like; and this was easily seen, by mixtures of spirits, but merely to their cornposiboiling them with slow heat, in a glass vessel, tion, as whether they easily incorporate with each
through which the whole may be clearly per- other, or there be rather (as an example) certain
ceived. But we merely mention this, intending winds and exhalations, or other spiritual bodies,
to treat of it more at large and more closely when which do not mix with common air, but only
we come to the discovery of the latent process; adhere to and float in it in globules and drops, and
for it should always be remembered that we do are rather broken and pounded by the air, than
not here treat of things themselves, but merely received into, and incorporated with it; this canpropose examples. not be perceived in common air, and other aeriform
42. In the nineteenth rank of prerogative in- substances, on account of the rarity of the bodies,
stances we will class supplementary or substitu- but an image, as it were, of this process, may be
tive instances, which we are also wont to call conceived in such liquids as quicksilver, oil,
instances of refuge. They are such as supply water, and even air, when broken and dissipated
information, where the senses are entirely defi- it ascends in small portions through water, and
cient, and we, therefore, have recourse to them also in the thicker kinds of smoke; lastly, in
when appropriate instances cannot be obtained. dust, raised and remaining in the air, in all of
This substitution is twofold, either by approxima- which there is no incorporation: and the above
tion or by analogy. For instance; there is no representation in this respect is not a bad one, if
known medium, which entirely prevents the effect it be first diligently investigated, whether there
of the magnet in attracting iron, neither gold, nor can be such a difference of nature between spisilver, nor stone, nor glass, wood, water, oil, rituous substances, as between liquids, for, then,
cloth, or fibrous bodies, air, flame, or the like. these images might conveniently be substituted
Yet, by accurate experiment, a medium may per- by analogy.
haps be found which would deaden its effect, And although we have observed of these supmore than another comparatively and in degree; plementary instances, that information is to be
as, for instance, the magnet would not, perhaps, derived froUl them, when appropriate instances
attract iron through the same thickness of gold are wanting, by way of refuge, yet, we would
as of air, or the same quantity of ignited as of have it understood, that they are also of great
cold silver, and so on: for we have not ourselves use, when the appropriate instances are at hand,
made the experiment, but it will suffice as an in order to confirm the information afforded by
example. Again, there is no known body which them; of which we will speak more at length.
is not susceptible of heat, when brought near the when our subject leads us, in due course, to the
fire. Yet, air becomes warm much sooner than supports of induction.
stone. These are examples of substitution by 43. In the twentieth rank of prerogative inapproximation. stances we will place lancing instances, which
Substitution by analogy is useful, but less sure, we are also wont (but for a different reason) to
and, therefore, to be adopted with some judgment. call twitching instances. We adopt the latter
It serves to reduce that which is not the object name, because they twitch the understanding, and
of the senses to their sphere, not by the percepti- the former because they pierce nature, whence we
ble operations of the imperceptible body, but by style them occasionally the instances of Demothe consideration of some similar perceptible critus.* They are such as warn the understandbody. For instance, let the subject for inquiry ing of the admirable and exquisite subtility of
be the mixture of spirits, which are invisible nature, so that it becomes roused and awakened
bodies. There appears to be some relation beI ween bodies and their sources or support. Now, * Alluding to his theory of atoms.