Francis Bacon.

Advancement of learning and novum organum online

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to call the instances of completion or non ultra. For the
powers and motions of bodies do not act and take effect through
indefinite and accidental, but through limited and certain
spaces ; and it is of great importance to practice that these
should be understood and noted in every nature which is in-
vestigated, not only to prevent deception, but to render practice
more extensive and efficient. For it is sometimes possible to ex-
tend these powers, and bring the distance, as it were, nearer,
as in the example of telescopes.

Many powers act and take effect only by actual touch, as in
the percussion of bodies, where the one does not remove the
other, unless the impelling touch the impelled body. External
applications in medicine, as ointment and plasters, do not exer-
cise their efficacy except when in contact with the body. Lastly,
the objects of touch and taste only strike those senses when in,
contact with their organs.

Other powers act at a distance, though it be very small, of
which but few have as yet been noted, although there be more
than men suspect; this happens (to take everyday instances)
when amber or jet attracts straws, bubbles dissolve bubbles,
some purgative medicines draw humors from above, and the
like. The magnetic power by which iron and the magnet, or
two magnets, are attracted together, acts within a definite and
narrow sphere, but if there be any magnetic power emanating
from the earth a little below its surface, and affecting the needle
in its polarity, it must act at a great distance.

Again, if there be any magnetic force which acts by sympathy
between the globe of the earth and heavy bodies, or between
that of the moon and the waters of the sea (as seems most prob-
able from the particular floods and ebbs which occur twice in
the month), or between the starry sphere and the planets, by


which they are summoned and raised to their apogees, these
must all operate at very great distances. Again, some con-
flagrations and the kindling of flames take place at very con-
siderable distances with particular substances, as they report of
the naphtha of Babylon. Heat, too, insinuates itself at wide
distances, as does also cold, so that the masses of ice which are
broken off and float upon the Northern Ocean, and are borne
through the Atlantic to the coast of Canada, become percepti-
ble by the inhabitants, and strike them with cold from a dis-
tance. Perfumes also (though here there appears to be always
some corporeal emission) act at remarkable distances, as is ex-
perienced by persons sailing by the coast of Florida, or parts of
Spain, where there are whole woods of lemons, oranges, and
other odoriferous plants, or rosemary and marjoram bushes,
and the like. Lastly, the rays of light and the impressions of
sound act at extensive distances.

Yet all these powers, whether acting at a small or great dis-
tance, certainly act within definite distances, which are well
ascertained by nature, so that there is a limit depending either
on the mass or quantity of the bodies, the vigor or faintness of
the powers, or the favorable or impeding nature of the medium,
all of which should be taken into account and observed. We
must also note the boundaries of violent motions, such as mis-
siles, projectiles, wheels, and the like, since they are also mani-
festly confined to certain limits.

Some motions and virtues are to be found of a directly con-
trary nature to these, which act in contact but not at a distance ;
namely, such as operate at a distance and not in contact, and
again act with less force at a less distance, and the reverse.
Sight, for instance, is not easily effective in contact, but requires
a medium and distance; although I remember having heard
from a person deserving of credit, that in being cured of a cata-
ract (which was done by putting a small silver needle within the
first coat of the eye, to remove the thin pellicle of the cataract,
and force it into a corner of the eye), he had distinctly seen the
needle moving across the pupil. Still, though this may be true,
it is clear that large bodies cannot be seen well or distinctly,
unless at the vertex of a cone, where the rays from the object
meet at some distance from the eye. In old persons the eye sees
better if the object be moved a little farther, and not nearer.
Again, it is certain that in projectiles the impact is not so violent
at too short a distance as a little afterwards. Such are the
observations to be made on the measure of motions as regards

There is another measure of motion in space which must not
be passed over, not relating to progressive but spherical motion
— that is, the expansion of bodies into a greater, or their con-


traction into a lesser sphere. For in our measure of this motion
we must inquire what degree of compression or extension bodies
easily and readily admit of, according to their nature, and at
what point they begin to resist it, so as at last to bear it no fur-
ther — as when an inflated bladder is compressed, it allows a
certain compression of the air, but if this be increased, the air
does not suffer it, and the bladder is burst.

We have proved this by a more delicate experiment. We took
a metal bell, of a light and thin sort, such as is used for salt-
cellars, and immersed it in a basin of water, so as to carry the
air contained in its interior down with it to the bottom of the
basin. We had first, however, placed a small globe at the bot-
tom of the basin, over which we placed the bell. The result
was, that if the globe were small compared with the interior of
the bell, the air would contract itself, and be compressed without
being forced out, but if it were too large for the air readily to
yield to it, the latter became impatient of the pressure, raised
the bell partly up, and ascended in bubbles.

To prove, also, the extension (as well as the compression)
which air admits of, we adopted the following method : — We
took a glass egg, with a small hole at one end ; we drew out the
air by violent suction at this hole, and then closed the hole with
the finger, immersed the egg in water, and then removed the
finger. The air being constrained by the effort made in suction,
and dilated beyond its natural state, and therefore striving to
recover and contract itself (so that if the egg had not been im-
mersed in water, it would have drawn in the air with a hissing
sound), now drew in a sufficient quantity of water to allow the
air to recover its former dimensions.

It is well ascertained that rare bodies (such as air) admit of
considerable contraction, as has been before observed; but
tangible bodies (such as water) admit of it much less readily,
and to a less extent. We investigated the latter point by the
following experiment : —

We had a leaden globe made, capable of containing about two
pints, wine measure, and of tolerable thickness, so as to support
considerable pressure. We poured water into it through an
aperture, which we afterwards closed with melted lead, as soon
as the globe was filled with water, so that the whole became
perfectly solid. We next flattened the two opposite sides with
a heavy hammer, which necessarily caused the water to occupy
a less space, since the sphere is the solid of greatest content ; and
when hammering failed from the resistance of the water, we
made use of a mill or press, till at last the water, refusing to
submit to a greater pressure, exuded like a fine dew through the
solid lead. We then computed the extent to which the original
space had been reduced, and concluded that water admitted such
a degree of compression when constrained by great violence.


The more solid, dry, or compact bodies, such as stones, wood,
and metals, admit of much less, and indeed scarcely any percep-
tible compression or expansion, but escape by breaking, slipping
forward, or other efforts ; as appears in bending wood, or steel
for watch-springs, in projectiles, hammering, and many other
motions, all of which, together with their degrees, are to be
observed and examined in the investigation of nature, either to
a certainty, or by estimation, or comparison, as opportunity

46. In the twenty-second rank of prerogative instances we
will place the instances of the course, which we are also wont
to call water instances, borrowing our expression from the
water hour-glasses employed by the ancients instead of those
with sand. They are such as measure nature by the moments
of time, as the last instances do by the degrees of space. For
all motion or natural action takes place in time, more or less
rapidly, but still in determined moments well ascertained by
nature. Even those actions which appear to take effect sud-
denly, and in the twinkling of an eye (as we express it), are
found to admit of greater or less rapidity.

In the first place, then, we see that the return of the heavenly
bodies to the same place takes place in regular times, as does
the flood and ebb of the sea. The descent of heavy bodies
towards the earth, and the ascent of light bodies towards the
heavenly sphere, take place in definite times, according to the
nature of the body, and of the medium through which it moves.
The sailing of ships, the motions of animals, the transmission of
projectiles, all take place in times the sums of which can be
computed. With regard to heat, we see that boys in winter
bathe their hands in the flame without being burnt ; and con-
jurers, by quick and regular movements, overturn vessels filled
with wine or water, and replace them without spilling the liquid,
with several similar instances. The compression, expansion and
eruption of several bodies, take place more or less rapidly, ac-
cording to the nature of the body and its motion, but still in
definite moments.

In the explosion of several cannon at once (which are some-
times heard at the distance of thirty miles), the sound of those
nearest to the spot is heard before that of the most distant.
Even in sight (whose action is most rapid), it is clear that a
definite time is necessary for its exertion, which is proved by
certain objects being invisible from the velocity of their motion,
such as a musket-ball ; for the flight of the ball is too swift to
allow an impression of its figure to be conveyed to the sight.

This last instance, and others of a like nature, have sometimes
excited in us a most marvellous doubt, no less than whether the
image of the sky and stars is perceived as at the actual moment


of its existence, or rather a little after, and whether there is not
(with regard to the visible appearance of the heavenly bodies) a
true and apparent time, as well as a true and apparent place,
which is observed by astronomers in parallaxes. It appeared so
incredible to us, that the images or radiations of heavenly bodies
could suddenly be conveyed through such immense spaces to the
sight, and it seemed that they ought rather to be transmitted in
a definite time. That doubt, however (as far as regards any
great difference between the true and apparent time), was sub-
sequently completely set at rest, when we considered the infinite
loss and diminution of size as regards the real and apparent
magnitude of a star, occasioned by its distance, and at the same
time observed at how great a distance (at least sixty miles)
bodies which are merely white can be suddenly seen by us. For
there is no doubt, that the light of the heavenly bodies not only
far surpasses the vivid appearance of white, but even the light
of any flame (with which we are acquainted) in the vigor of its
radiation. The immense velocity of the bodies themselves,
which is perceived in their diurnal motion, and has so astonished
thinking men, that they have been more ready to believe in the
motion of the earth, renders the motion of radiation from them
(marvellous as it is in its rapidity) more worthy of belief. That
which has weighed most with us, however, is, that if there were
any considerable interval of time between the reality and the
appearance, the images would often be interrupted and confused
by clouds formed in the mean time, and similar disturbances of
the medium. Let this suffice with regard to the simple measures
of time.

It is not merely the absolute, but still more the relative meas-
ure of motions and actions which must be inquired into, for
this latter is of great use and application. We perceive that
the flame of fire-arms is seen sooner than the sound is heard,
although the ball must have struck the air before the flame,
which was behind it, could escape : the reason of which is, that
light moves with greater velocity than sound. We perceive,
also, that visible images are received by the sight with greater
rapidity than they are dismissed, and for this reason, a violin
string touched with the finger appears double or triple, because
the new image is received before the former one is dismissed.
Hence, also, rings when spinning appear globular, and a lighted
torch, borne rapidly along at night, appears to have a tail. Upon
the principle of the inequality of motion, also, Galileo attempted
an explanation of the flood and ebb of the sea, supposing the
earth to move rapidly, and the water slowly, by which means the
water, after accumulating, would at intervals fall back, as is
shown in a vessel of water made to move rapidly. He has, how-
ever, imagined this on data which cannot be granted (namely,


the earth's motion), and besides, does not satisfactorily account
for the tide taking place every six hours.

An example of our present point (the relative measure of
motion), and, at the same time, of its remarkable use of which
we have spoken, is conspicuous in mines filled with gunpowder,
where immense weights of earth, buildings, and the like, are
overthrown and prostrated by a small quantity of powder ; the
reason of which is decidedly this, that the motion of the expan-
sion of the gunpowder is much more rapid than that of gravity,
which would resist it, so that the former has terminated before
the latter has commenced. Hence, also, in missiles, a strong
blow will not carry them so far as a sharp and rapid one. Nor
could a small portion of animal spirit in animals, especially in
such vast bodies as those of the whale and elephant, have ever
bent or directed such a mass of body, were it not owing to the
velocity of the former, and the slowness of the latter in resisting
its motion.

In short, this point is one of the principal foundations of the
magic experiments (of which we shall presently speak), where
a small mass of matter overcomes and regulates a much larger,
if there but be an anticipation of motion, by the velocity of one
before the other is prepared to act.

Finally, the point of the first and last should be observed
in all natural actions. Thus, in an infusion of rhubarb the pur-
gative property is first extracted, and then the as.tringent ; we
have experienced something of the same kind in steeping violets
in vinegar, which first extracts the sweet and delicate odor of
the flower, and then the more earthy part, which disturbs the
perfume ; so that if the violets be steeped a whole day, a much
fainter perfume is extracted than if they were steeped for a
quarter of an hour only, and then taken out ; and since the
odoriferous spirit in the violet is not abundant, let other and
fresh violets be steeped in the vinegar every quarter of an hour,
as many as six times, when the infusion becomes so strength-
ened, that although the violets have not altogether remained
there for more than one hour and a half, there remains a most
pleasing perfume, not inferior to the flower itself, for a whole
year. It must be observed, however, that the perfume does not
acquire its full strength, till about a month after the infusion.
In the distillation of aromatic plants macerated in spirits of
wine, it is well known that an aqueous and useless phlegm rises
first, then water containing more of the spirit, and lastly, water
containing more of the aroma; and many observations of the
like kind, well worthy of notice, are to be made in distillations.
But let these suffice as examples.

47. In the twenty-third rank of prerogative instances we will
place instances of quantity, which we are also wont to call the


doses of nature (borrowing a word from medicine). They are
such as measure the powers by the quantity of bodies, and point
out the effect of the quantity in the degree of power. And in
the first place, some powers only subsist in the universal quan-
tity, or such as bears a relation to the confirmation and fabric
of the universe. Thus the earth is fixed, its parts fall. The
waters in the sea flow and ebb, but not in the rivers, except
by the admission of the sea. Then, again, almost all particular
powers act according to the greater or less quantity of the body.
Large masses of water are not easily rendered foul, small are.
New wine and beer become ripe and drinkable in small skins
much more readily than in large casks. If an herb be placed in
a considerable quantity of liquid, infusion takes place rather
than impregnation ; if in less, the reverse. A bath, therefore,
and a light sprinkling, produce different effects on the human
body. Light dew, again, never falls, but is dissipated and in-
corporated with the air ; thus we see that in breathing on gems,
the slight quantity of moisture, like a small cloud in the air,
is immediately dissolved. Again, a piece of the same magnet
does not attract so much iron as the whole magnet did. There
are some powers where the smallness of the quantity is of more
avail; as in boring, a sharp point pierces more readily than a
blunt one ; the diamond, when pointed, makes an impression
on glass, and the like.

Here, too, we must not rest contented with a vague result,
but inquire into the exact proportion of quantity requisite for
a particular exertion of power ; for one would be apt to suppose
that the power bears an exact proportion to the quantity ; that
if a leaden bullet of one ounce, for instance, would fall in a given
time, one of two ounces ought to fall twice as rapidly, which is
most erroneous. Nor does the same ratio prevail in every kind
of power, their difference being considerable. The measure,
therefore, must be determined by experiment, and not by prob-
ability or conjecture.

Lastly, we must in all our investigations of nature observe
what quantity, or dose, of the body is requisite for a given effect,
and must at the same time be guarded against estimating it at
too much or too little.

48. In the twenty-fourth rank of prerogative instances we
will place wrestling instances, which we are also wont to call
instances of predominance. They are such as point out the
predominance and submission of powers compared with each
other, and which of them is the more energetic and superior, or
more weak and inferior. For the motions and effects of bodies
are compounded, decomposed, and combined, no less than the
bodies themselves. We will exhibit, therefore, the principal
kinds of motions or active powers, in order that their compara-


tive strength, and thence a demonstration and definition of the
instances in question, may be rendered more clear.

Let the first motion be that of the resistance of matter, which
exists in every particle, and completely prevents its annihila-
tion ; so that no conflagration, weight, pressure, violence, or
length of time can reduce even the smallest portion of matter
to nothing, or prevent it from being something, and occupying
some space, and delivering itself (whatever straits it be put to),
by changing its form or place, or, if that be impossible, remaining
as it is ; nor can it ever happen that it should either be nothing
or nowhere. This motion is designated by the schools (which
generally name and define everything by its effects and incon-
veniences rather than by its inherent cause) by the axiom, that
two bodies cannot exist in the same place, or they call it a motion
to prevent the penetration of dimensions. It is useless to give
examples of this motion, since it exists in every body.

Let the second motion be that which we term the motion of
connection, by which bodies do not allow themselves to be sepa-
rated at any point from the contact of another body, delighting,
as it were, in the mutual connection and contact. This is called
by the schools a motion to prevent a vacuum. It takes place
when water is drawn up by suction or a syringe, the flesh by
cupping, or when the water remains without escaping from per-
forated jars, unless the mouth be opened to admit the air, and
innumerable instances of a like nature.

Let the third be that which we term the motion of liberty, by
which bodies strive to deliver themselves from any unnatural
pressure or tension, and to restore themselves to the dimensions
suited to their mass ; and of which, also, there are innumerable
examples. Thus, we have examples of their escaping from
pressure, in the water in swimming, in the air in flying, in the
water again in rowing, and in the air in the undulation of the
winds, and in springs of watches. An exact instance of the
motion of compressed air is seen in children's popguns, which
they make by scooping out elder-branches or some such matter,
and forcing in a piece of some pulpy root or the like, at each
end ; then they force the root or other pellet with a ramrod
to the opposite end, from which the lower pellet is emitted and
projected with a report, and that before it is touched by the
other piece of root or pellet, or by the ramrod. We have ex-
amples of their escape from tension, in the motion of the air
that remains in glass eggs after suction, in strings, leather, and
cloth, which recoil after tension, unless it be long continued.
The schools define this by the term of motion from the form
of the element ; injudiciously enough, since this motion is to be
found not only in air, water, or fire, but in every species of
solid, as wood, iron, lead, cloth, parchment, etc., each of which


has its own proper size, and is with difficulty stretched to any
other. Since, however, this motion of liberty is the most obvi-
ous of all, and to be seen in an infinite number of cases, it will
be as well to distinguish it correctly and clearly ; for some most
carelessly confound this with the two others of resistance and
connection ; namely, the freedom from pressure with the for-
mer, and that from tension with the latter, as if bodies when
compressed yielded or expanded to prevent a penetration of
dimensions, and when stretched rebounded and contracted them-
selves to prevent a vacuum. But if the air, when compressed,
could be brought to the density of water, or wood to that of
stone, there would be no need of any penetration of dimensions,
and yet the compression would be much greater than they actu-
ally admit of. So if water could be expanded till it became
as rare as air, or stone as rare as wood, there would be no need
of a vacuum, and yet the expansion would be much greater than
they actually admit of. We do not, therefore, arrive at a pene-
tration of dimensions or a vacuum before the extremes of con-
densation and rarefaction, whilst the motion we speak of stops
and exerts itself much within them, and is nothing more than
a desire of bodies to preserve their specific density (or, if it be
preferred, their form), and not to desert them suddenly, but
only to change by degrees, and of their own accord. It is, how-
ever, much more necessary to intimate to mankind (because
many other points depend upon this), that the violent motion
which we call mechanical, and Democritus (who, in explaining
his primary motions, is to be ranked even below the middling
class of philosophers) termed the motion of a blow, is nothing
else than this motion of liberty, namely, a tendency to relaxation
from compression. For in all simple impulsion or flight through
the air, the body is not displaced or moved in space, until its
parts are placed in an unnatural state, and compressed by the
impelling force. When that takes place, the different parts
urging the other in succession, the whole is moved, and that
with a rotatory as well as progressive motion, in order that the
parts may, by this means also, set themselves at liberty, or more
readily submit. Let this suffice for the motion in question.

Let the fourth be that which we term the motion of matter,
and which is opposed to the last; for in the motion of liberty,

Online LibraryFrancis BaconAdvancement of learning and novum organum → online text (page 47 of 51)