The works of Francis Bacon, lord chancellor of England.

388 NOVUM ORGANUM. BooK II.
migrating towards corruption in the same nature, and it is a better instance than gold for the puris that of dissolving froth, or snow, for they lose pose of indicating the form of weight. For gold
their whiteness, and assume the transparency of is solid and consistent, which qualities must be
water in its pure state without air. referred to density, but quicksilver is liquid, and
Nor should we by any means omit to state, that teeming with spirit, yet much heavier than the
under migrating instances we must comprehend diamond and other substances considered to 1e
not only those which pass towards generation and most solid. Whence it is shown that the form
destruction, but also those which pass towards in- of gravity or weight predominates only in the
crease or decrease, for they too assist in the disco- quantity of matter, and not in the close fitting
very of the form, as is clear from our definition of of it.
a form, and the table of degrees. Hence, paper, 25. In the fourth rank of prerogative instances
which is white when dry, is less white when we will class clandestine instances; which we
moistened, (from the exclusion of air and admis- are also wont to call twilight instances. The3
sion of water,) and tends more to transparency. are, as it were, opposed to the conspicuous inThe reason is the same as in the above instances. stances; for they show the required nature in its
24. In the third rank of prerogative instances, lowest state of efficacy, and, as it were, its cradle
we will class conspicuous instances, of which we and first rudiments, making an effort, and a sort
spoke in our first vintage of the form of heat, and of first attempt, but concealed and subdued by a
which we are also wont to call coruscations, or contrary nature. Such instances are, however,
free and predominant instances. They are such of great importance in discovering forms, for, as
as show the required nature in its bare substantial the conspicuous tend easily to differences, so do
shape, and at its height, or greatest degree of the clandestine best lead to genera; that is, to
power, emancipated and free from all impedi- those common natures of which the required
ments, or, at least, overcoming, suppressing, and natures are only the limits.
restraining them by the strength of its qualities. As an example: let consistency, or that which
For, since every body is susceptible of many confines itself, be the required nature, the cppounited forms of natures in the concrete, the con- site of which is a liquid or flowing state. The
sequence is, that they mutually deaden, depress, clandestine instances are such as exhibit some
break, and confine each other, and the individual weak and low degree of consistency in fluids, as
forms are obscured. But there are some subjects a water bubble, which is a sort of consistent and
in which the required nature exists in its full bounded pellicle, formed out of the substance of
vioour rather than in others, either from the ab- the water. So eaves' droppings, if there be
sence of any impediment or the predominance of enough water to follow them, draw themselves
its quality. Such instances are eminently con- out into a thin thread, not to break the continuity
spicuous. But, even in these, care must be taken, of the water, but if there be not enough to follow,
and the hastiness of the understanding checked, the water forms itself into a round drop, which
for, whatever makes a show of the form, and is the best form to prevent a breach of continuity:
forces it forward, is to be suspected, and recourse and at the moment the thread ceases, and the
must be had to severe and diligent exclusion. water begins to fall in drops, the thread of water
For example; let heat be the required nature. recoils upwards to avoid such a breach. Nay, in
The thermometer is a conspicuous instance of the metals, which, when melted, are liquid, but more
expansive motion, which (as has been observed) tenacious, the melted drops often recoil and are
constitutes the chief part of the form of heat. suspended. There is something similar in the
For, although flame clearly exhibit expansion, instance of the child's looking-glass, which little
yet, from its being extinguished every moment, boys will sometimes form of spittle between
it e 3ais not exhibit the progress of expansion. rushes, and where the same pellicle of water is
Boiling water, again, from its rapid conversion observable: and still more in that other amuseinto vapour, does not so well exhibit the expan- ment of children, when they take some water
sion of water in' its own shape: whilst red-hot rendered a little more tenacious by soap, and iniion, and the like, are so far from showing this flate it with a pipe, forming the water into a sort
progress, that, on the contrary, the expansion of castle of bubbles, which assumes such conitself is scarcely evident to the senses, on account sistency by the interposition of the air, as to
of its spirit being repressed and weakened by the admit of being thrown some little distance withcompact and coarse articles which subdue and out bursting. The best example is that of froth
restrain it. But the thermometer strikingly ex- and snow, which assume such consistency as
hibits the expansion of the air, as being evident almost to admit of being cut, although composed
and progressive, durable, and not transitory. of air and water, both liquids. All these circumTake another example. Let the required nature stances clearly show that the terms liquid and
be weight. Quicksilveris a conspicuous instance consistent are merely vulgar notions adapted to
of weight; for it is far heavier than any other the sense, and that in reality all bodies have a
uiabstance except gold, which is not much heavier; tendency to avoid a breach of continuity, faint