The works of Francis Bacon, lord chancellor of England.

BOOK II. NOVUM ORGANUM. 411
is requisite for a given effect, and must at the or some such matter, and forcing in a piece of
same time be guarded against estimating it at too some pulpy root, or the like, at each end; then
much or too little. they force the root or other pellet with a ramrod
48. In the twenty-fourth rank of prerogative to the opposite end, from which the lower pellet
instances, we will place wrestling instances, is emitted and projected with a report, and that
which we are also wont to call instances of pre- before it is touched by the other piece of root or
dominance. They are such as point out the pre- pellet, or by the ramrod. We have examples of
dominance and submission of powers compared their escape from tension, in the motion of the
with each other, and which of them is the more air that remains in glass eggs after suction, in
energetic and superior, or more weak and inferior. strings, leather, and cloth, which recoil after tenFor the motions and effects of bodies are com- sion, unless it be long continued. The schools
pounded, decomposed, and combined, no less define this by the term of motion "Ifrom the form
than the bodies themselves. We will exhibit, of the element;" injudiciously enough, since this
therefore, the principal kinds of motions or active motion is to be found not only in air, water, or
powers, in order that their comparative strength, fire, but in every species of solid, as wood, iron,
and thence a demonstration and definition of the lead, cloth, parchment, &c., each of which has
instances in question, may be rendered more clear. its own proper size, and is with difficulty stretched
Let the first motion be that of the resistance of to any other. Since, however, this motion of
matter, which exists in every particle, and corn- liberty is the most obvious of all, and to be seen
pletely prevents its annihilation; so that no con- in an infinite number of cases, it will be as well
flagration, weight, pressure, violence, or length to distinguish it correctly and clearly; for some
of time, can reduce even the smallest portion of most carelessly confound this with the two others
matter to nothing, or prevent it from being some- of resistance and connection; namely, the freething, and occupying some space, and delivering dom from pressure with the former, and that from
itself, (whatever straits it be put to,) by changing- tension with the latter; as if bodies when cornits form-or place, or, if that be impossible, re- pressed yielded or expanded to prevent a penemaining as it is, nor can it ever happen that it tration of dimensions, and, when stretched,
should either be nothing or nowhere. This mo- rebounded and contracted themselves to prevent
tion is designated by the schools (which generally a vacuum. But if the air, when compressed,
name and define every thing by its effects and in- could be brought to the density of water, or wood
conveniences, rather than by its inherent cause) to that of stone, there would be no need of any
by the axiom, " that two bodies cannot exist in penetration of dimensions, and yet the compresthe same place," or they call it a motion, "' to pro- sion would be much greater than they actually
vent the penetration of dimensions." It is use- admit of. So, if water could be expanded till it
less to give examples of this motion, since it exists became as rare as air, or stone as rare as wood,
in every body. there would be no need of a vacuum, and yet the
Let the second motion be that which we term expansion would be much greater than they acthe motion of connexion, by which bodies do not tually admit of. We do not, therefore, arrive at
allow themselves to be separated at any point from a penetration of dimensions or a vacuum, before
the contact of another body, delighting, as it the extremes of condensation and rarefaction,
were, in the mutual connexion and contact. This whilst the motion we speak of stops and exerts
is called by the schools a motion "4 to prevent a itself much within them, and is nothing more
vacuum." It takes place when water is drawn than a desire of bodies to preserve their specific
up by suction or a syringe, the flesh by cupping, density, (or, if it be preferred, their form,) and
or when the water remains without escaping from not to desert them suddenly, but only to change
perforated jars, unless the mouth be opened to by degrees, and of their own accord. It is,
admit the air, and innumerable instances of a however, much more necessary to intimate to
like nature. mankind (because many other points depend
Let the third be that which we term the motion upon this) that the violent motion which we call
of liberty; by which bodies strive to deliver mechanical, and Democritus (who, in explaining
themselves from any unnatural pressure or ten- his primary motions, is to be ranked even below
sion, and to restore themselves to the dimensions the middling class of philosophers) termed the
suited to their mass; and of which, also, there motion of a blow, is nothing else than this motion
are innumerable examples. Thus, we have ex- of liberty, namely, a tendency to relaxation from
amples of their escaping from pressure, in the compression. For, in all simple impulsion or
water in swimming, in the air in flying, in the flight through the air, the body is not displaced
water again in rowing, and in the air in the un. or moved in space, until its parts are placed in
dulations of the winds, and in the springs of {an unnatural state, and compressed by the impelwatches. An exact instance of the motion of ling force. When that takes place, the different
compressed air is seen in children's popguns, parts urging the other in succession, the whole is
which they make by scooping out elder branches, moved, and that with a rotatory as well as pro