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bottom: you shall hear the sound of the tongs | every part of the air, not the whole in the whole knapped in the vessel of silver much more re- air, unless where the opening or passage is ex sounding than in the wooden one. Whereas, if ceedingly strait. For if one stand in any place the two vessels were empty, and you knapped utterly closed, so as the sound may not penetrate the tongs at the same distance, there should be at all, and that in any part soever of a sphere of little difference, or none. Whence it appears, sound, and there be a small opening made, the first, that where is no air that can be elided, but articulate voice shall enter through that opening, only water, sound is given; next, that the sound and in fine through as many openings as you given by the percussion communicates better shall choose to make through the whole round of with the vessel through water than through air. the sphere of sound so as it is manifest that that The mouth being close shut, there is made a whole articulation of sound is conveyed entire in murmur (such as dumb persons use to make) by these minutest parts of the air, not less than if the throat; if the nostrils likewise be fast closed, the air were at large on every side. no murmur can be made. Whence it appears, that that sound by the throat is not effected unless through the opening which lies between the throat and the nostrils.

Of the Carriage of Sounds, and their Direction or Spreading; and of the Area which Sound fills, together and severally.

All sound is diffused in a sphere from the place of the percussion, and fills the whole area of this sphere to a certain limit, upwards, downwards, sideways, and every way.

Throughout this orb the sound is loudest close to the stroke; thence, in the proportion of the distance, it grows more faint, until it vanishes. The limits of this sphere are extended some little by reason of the quickness of hearing; yet is there something uttermost, whither, to the most delicate sense, sound reaches not.

There is something, I think, in the direction of the first impulsion; for, if a man should stand in an open pulpit in the fields, and shout, the voice, I judge, should be further heard forwards from the speaker than behind. So, if ordnance, or a harquebuss be discharged, I judge that the sound shall be further heard before the ordnance or harquebuss than behind it.

Whether there be any thing in the ascension of sound upwards, or in the descension of sound downwards, which may further sound, or make it cease nearer, doth not appear. The sound is indeed well heard, if one speak from a high window or turret, by those who stand upon the ground; and, contrariwise, being uttered by those that stand upon the ground from the window or turret, but by whether more easily, or further off, let better inquiry be made.

It is, however, to be observed whether sounds proceeding from the greater pulsations of the air (such as are made by the discharge of ordnance) become not more exile when they enter by those small apertures; for it may be that the subtilties of sound shall enter unconfused, but the whole crash, or roar, not so well.

The rays of visible bodies do not strike the sense, unless they be conveyed through the medium in straight lines, and the interposition of any opaque, in a right line, intercepts the sight, although every thing else be on all sides wholly open. But sound, if there be a dilatation or passage, whether by arching over, or by inverted arching downwards, or laterally, or even by winding, perishes not, but arrives. Nevertheless, I judge that sound is more strongly carried in straight lines, betwixt the pulsations and the ear, and that by its archings and windings it is somewhat broken; as, if there be a wall betwixt the speaker and the hearer, I think that the voice shall not be so well heard as if the wall were away. I judge, too, that if the speaker or the hearer be placed at a little distance from the wall, the voice shall be better heard than nigh unto the wall, because the arching so much the less departs from a right line. But this also would be further in quired.

If the ear be laid to the one end of any tube or long hollow trunk, and a voice speak softly at the other opening of the tube, such a voice shall be heard, which, being as softly spoken in the air at large, should not arrive, nor be heard. Whence it is clear, that that confining of the air helps to the conveying of the voice, without confusion.

It is also a common opinion, that, other things being equal, the voice is better heard within doors than abroad; but whether the voice be better heard when the ear is out of doors, and the voice within the house; or contrariwise, when the voice is out of doors, and the ear within the house, may be further inquired; albeit herein also the opinion is received, that what is abroad is better heard within doors, than what is within, abroad.

Pulpits are used for speaking in assemblies, and generals did usually speak standing upon mounds of sods; yet is it is no wise hence confirmed that sound easilier descends than it rises, since the cause hereof may be the liberty of the air in the higher place, not thronged or hindered, as below amongst the crowd, but not the readier motion downwards. Therefore, let not the con- It is common to hearing and sight, and, indeed, templation stay in this instance, but let a trial be in a certain measure, to the other senses, that the made where other things are equal. attention of the perceiving mind, and express di The power of the sound is received whole in rection to perceiving, help somewhat to perceiv

ing, as when one looks steadfastly, or (as they of the Variety of the Bodies which yield Sound; say) pricks his ears.

Sounds are not carried so far, articulate and distinct, as their species, and a confused coil of them; for the hum of voices can be heard where the articulate words themselves are not heard; and a confused tinkling of music, when the harmony itself or tune is not heard.

and the Instruments; and of the Species of Sounds which occur.

The kinds of sounds appear to receive such a division: loud, soft, sharp or treble, base; musical, unmusical; interior or whispering, exterior or sounding; simple, compounded, original, reflected; so as they are divisions six.

The stronger the first pulsation shall be, and the dilatation the more free, and without let, the greater is the sound given the weaker the percussion, and more disturbed the dilatation, the less. Treble sounds are carried as far, and perchance farther than base. Let this be better inquired. Accordingly as the concave of a bell shall be greater, it giveth a baser sound; the less, the more treble.

The bigger a string, the baser sound it shall yield; the less, the more treble.

A string, the more tightly strained, the more treble sound shall it yield; the looser, the baser: so as a little bigger string more tightly strained, and a less more slackly, shall give the same note. In trumpets, in like wise, in flutes, horns, and recorders, pipes, also in the mouth of a man whistling, the more narrow and straight they are, they give the more treble sound; the wider, or more open, the baser.

Sound is preserved, at the best, in a hollow trunk. Therefore let there be taken a hollow trunk of a good length, and let it be put out from the window of a lower chamber; let one speak by thrusting of his head out of the window, at one end of the trunk, as softly as ever he may : let another lay his ear to the other end of the trunk, standing below upon the ground: let this be done in like wise reversely, by speaking from below, and laying to of the ear above, and from this trial let a judgment be made, whether the voice ascend or descend more easily, or even alike. They deliver for certain, that there be some places and buildings so vaulted, that if one stand in a certain part of the chamber, and speak, he can be better heard at some distance than near. All harmony appeareth to sound somewhat fuller and deeper at a little remoteness from the place of the sound than near; so as something should seem to happen to hearing about sound, like as happeneth to sight about visible species, that some removal from the organ of the sense furthereth the perception of the sense. But in that opinion may be twofold error. First, because in the act of sight there be, perhaps, beams required from the object to the pupil, which there cannot be where the object toucheth the pupil, In some stringed instruments (as in the viol, which between the hearing and the sound is not citterns, and the like) men have found a skill for required. But much rather, because to seeing is the straining of the strings, beyond the first light needed. But an object touching the pupil straining, so as compressing them with the finintercepts the light; whereas nothing of this kindgers lower down or higher up, they strain them befalls to hearing. And, in the second place, be- to the alteration of the note. cause to sight there needeth not always a medium; forasmuch as, in the removing of cataracts of the eyes, the little silver needle wherewith the cataracts are removed, even when it moveth upon the pupil within the coat of the eye, is excellently


In objects of sight, if the eye be placed in the dark, and the object in the light, it shall do well; but if the object be placed in the dark, and the eye in the light, you shall not see. So, if a thin veil or net-work be cast over the eyes, the object is well seen; if upon the object, it confounds sight. And albeit, that perhaps neither of these agreeth to sound and hearing, yet may they advertise us that trials be made, whether the ear set against the hollow trunk, if the sound be made at a distance in the air at large, or conversely, the sound be produced at the hollow trunk, the ear being placed at a distance in the air at large, favour more the perception of the


In flutes, the air, issuing by a hole nearer the breath, yields a more treble sound; by one more distant, a baser: so a little bigger flute by the nearer hole, and a smaller by the more removed, may give the same note.

If a drinking-cup of glass or silver be taken and fillipped, if the water stand higher in the cup, and the cup be fuller, it will give a more treble sound; if lower, and the cup be more empty, a baser.

In a hollow pipe, such as they use for shooting of birds, if one whistle with the mouth, setting the mouth to one end of the tube, the sound is dulled, truly, to the bystander; but if the ear be laid to the other end, it gives a most sharp sound, so as it shall hardly be borne.

Let there be a trial made with a trunk, in the part where the ear is laid, narrow, in the part where the mouth is set, wider, and conversely; whether the sound be rendered more treble or baser, after the manner of mirrors, which contract or enlarge the objects of sight.

of the Multiplication, Majoration, Diminution, and Fraction of Sound.

It would be seen in what, how, way, manner, sound can be artificially magnified and multiplied.

Mirrors do effect both in sight. Now, the sudden reflection of sound seems to turn to augmentation; for if the voice and echo be yielded together, need is that the sound be not distinguished, but magnified. Therefore, sounds upon rivers are greater, the water resounding and blending itself with the original sound.

I have also noted that when a round-house is made in water-conduits, then a long vault, and then a greater chamber, (such as is to be seen in the fields by Charing Cross near London,) if you cry at the window or slit of the round-house, and one stand by the window of the greater chamber, a far more fearful roaring is heard than by one standing where the cry is made.

I bethink me that in the play of puppets, the speaking is such as it is heard distinctly, but far sharper and more exile than in the air at large; as happens in mirrors that render letters far smaller than they are in the ordinary medium so as sound appears plainly possible by art to be both amplified and rendered more exile.

Children hold the horn of a bent bow betwixt their teeth, and with an arrow strike the string, whence is produced a more resounding sound, and a far greater boom, than if the bow were not held in the teeth; which they ascribe to the consent which the bones of the teeth have with the bone of hearing; since, conversely also, by a certain harsh sound in the hearing, the teeth too be set on edge.

In like manner, let a lance touch the wood of the belly of an harp, especially of the hole in it at the hollow end, and be held with the teeth at the other end, and the harp struck; the sound is made greater by taking hold with the teeth, that is to say, to him that so taketh hold.

Of the Repercussion of Sounds and Echo. The repercussion of sounds (which we call echo) can be taken for an argument that sound is not a local motion of the air; for if it were, the repercussion should be made in manner conformable to the original, as happens in all corporeal repercussions. But in sound, wherein such an exact generation is required, as in the voice, which hath so many organs, and in musical inwhich yield the repercussed sound have nothing struments, which be curiously framed, the things such, but are merely rude, having almost nothing save this, that sound passes not through them.

Of the Consents and Dissents of Audibles and Visibles, and of other so called Spiritual Species.

They agree in these :

Both are diffused in a spherical compass or orb, and fill the whole area of that sphere, and are carried to very distant spaces, and wax faint by degrees, according to the distance of the object, then vanish. Both carry their figurations and differences into minute portions of their orb, entire and unconfused, so as they are perceived through small crannies no otherwise than in an open place.

Both are of exceedingly sudden and swift generation and dilatation, and conversely they are extinguished, and perish suddenly and quickly.

Both take and convey minute and exquisite differences, as of colours, figures, motions, distances, in visibles; of articulate voices, of musical tones, and of their swift changes and trepidation, in audibles.

Both, in their virtue and force, appear neither to emit any corporeal substance into their mediums or their orb, nor even to give forth or provoke a local perceptible motion in their mediums, but to convey certain spiritual species, of which the nature and manner is unknown.

Both appear to be not generative of any other virtue or quality besides their proper virtue, and so far to work, being else barren.

Both in their proper action appear, as if corporeally, to work three things. The first, that the stronger object drowns and confounds the weaker; as the light of the sun, the light of a candle, the report of ordnance, the voice. The second, that the more excellent object destroys the weaker sense; as the light of the sun, the eye, a violent

It is most assured (however unnoted) that the force, which after the first percussion carries on balls, or arrows, or darts, and the like, is situated in the minute parts of the body discharged, and not in the air continually carrying it, like a boat in the water. This being premised, it may be considered whether sound might not be lessened in ordnance or a harquebuss, without much weakening of the percussion, in this manner. Let there be a harquebuss made with a barrel of a pretty strength, so as it break not easily; in the barrel let there be four or five holes made, not like chinks, but round, about the middle of the barrel. The percussion hath already gotten its force, excepting so far as by reason of the length of the barrel it may be increased; but the percus-sound close at the ear, the hearing. The third, that sion of the air at the mouth of the harquebuss, which generates the sound, will be much attenuated by the emission of sound through those holes in the middle of the barrel, before that the air enclosed arrive at the mouth of the harquebuss. Therefore it is probable that the sound and boom shall by many parts be diminished.

both are repercussed, as in mirrors and the echo.

Neither doth the object of the one confound or hinder the object of the other; as light or colour, sound, or contrariwise.

Both affect the sense in animals, and that by objects in greater or less degrees grateful or odious but they affect also after their own man

ner inanimates proportionate, and having (as cured of cataracts of the eyes, when the little silseemeth) a conformity with the organs of the senses; as colours, a mirror, that is crystalline like the eye; sounds, the places of reverberation, which seem, likewise, to resemble the bone and cavern of the ear.

ver needle moved over the very pupil of his eye, and did touch it, he, without any medium, (that silver needle being far narrower than the pupil itself of the eye,) saw perfectly the needle. The second, that the cave of the ear is distinctly inter

Both work diversely, accordingly as they have posed before the organ of hearing, so as, being their mediums well or ill disposed.

To both the medium the most conducible and propitious is the air. In both the stretching of the sense, and, as it were, its erection to perceiving, availeth somewhat in more nice objects.

They differ in these:

The species of visibles appear to be as if emissions of beams from the visible body, almost like odours. But the species of audibles appear more to partake of a local motion, like the percussions which are made in the air: that whereas bodies for the most part work in two manners, by communication of their nature, or by an impression or signature of their motion, that diffusion in visibles appeareth more to partake of the former manner; in audibles, of the latter.

The dilatation of sounds appears to be more evidently carried by the air than of visibles. For I judge that a vehement wind shall not so much hinder any visible afar off, as a sound; I understand the wind blowing contrary.

It is a notable difference, whence also many less differences flow, that visibles (original light excepted) are not carried but by right lines, whilst sounds are carried by arcuate lines.

Hence it happens, that visibles confound not one another, that are represented together: sounds contrarily. Hence it happens, that the solidity of the substance seems not greatly to hinder sight, provided only the positions of the parts of the body be after a simple order and with straight passages, as in glass, water, crystal, diamond; but a little silk or linen cloth breaks the sight, though they be bodies very thin and porous; but cloths of this kind little or nothing hinder hearing, which those solids do exceedingly. Hence it happens, that unto the reverberation of visibles a small mirror suffices, or like transpicuous body, let it be only placed in a right line, where the visibles pass; but unto making of the reverberation of echo, it needeth also to confine the sound from the side, because it is carried to all sides. The visible object is further carried, in proportion, than sound.

Visibles, too nearly approached to the eye, are not so well seen as at some little distance, so as the beams may meet in a more acute angle; but in hearing, the nearer the better. But herein there may be twofold error. The first, because to seeing there is required light; but if the object be brought very near to the eye, this is shut out. For I have heard of one trustworthy, which was

without, the sound is altogether unable to touch the bone and membrane of hearing.

The species of sight are more swiftly conveyed than sounds, as appeareth in the flash and report of guns; also in lightning and thunder, where the thunder is heard after a while.

I conceive also that the species of sound do hang longer in the air than visibles. For, although neither do these perish on the instant, as we see in a ring spinning, and lute-strings fillipped, and in twilight and the like; yet I deem that sounds, for that they are carried by the wind, stay longer.

The beams of light being gathered, induce heat also, which is an action diverse from the visible quality. In like manner, if it be true that shouts have cast down birds flying over, that is also an action exceedingly diverse from the audible quality.

There seemeth not in visibles to be found an object as odious, and noisome to the sense, as in audibles; but they affect it more evenly; for things foul to sight rather offend by moving of the fancy concerning foul things than of themselves; but in audibles the grating of a saw that is sharpened, and other like sounds, cause a horror; and a discordant note in music is straightways refused and loathed.

It is not assured, that there is refraction in sounds, as in beams. But, doubtless, sounds do rebound; but that is to be ascribed to reflection. For, I do not think, if sounds pass through diverse mediums, as air, cloth, wood, that there be one place of the sound, where it is carried, another where it is heard, which is the property of refraction; but refraction seems to depend upon action, in right lines, which pertains not to sound.

But contraction of sound, and its dilatation, according to the disposition of the medium, happens, undoubtedly, as in the speaking of puppets, and under water: the sound is contracted within that cell, which abroad is dispersed; as by mirrors visibles are dilated and contracted.

A tremulous medium (as smoke in visibles) makes the visible objects also to tremble; but in sounds nothing such is yet found, unless, perchance, the rise and fall by winds. For the trembling in the nightingale-pipe is trembling of the percussion, not of the medium.

Going from great light into the dark, or out of the dark into the light, the sight is some little confused; but whether the like be after very loud noises, or a great silence, would be inquired.

Of the Quickness of the Generation and Extinction | is, at King's College, in Cambridge, a certain of Sound, and the time in which they are effected. wooden building, in which there hang bells, and that when the bells ring, it is shaken. But whatsoever that hidden motion be, which is sound, it appears that neither is it engendered without perceptible motion in the first pulsation, and that again by the perceptible motion of the air it is carried or hindered.

All sound is exceeding quickly generated, and quickly perishes. But the swiftness of its motion and of its differences, appears a thing not so wonderful. For the motion of the fingers upon a lute, or of the breath in the pipe or flute, are found to be exceedingly swift: and the tongue itself (no very exquisite organ) goes through as many motions as letters; but that sounds should not only be so speedily generated but that they should also, by their momentary force and impression, as it were, suddenly fill so great space, is matter worthy of the highest admiration. For instance, a man in the middle of a field, speaking aloud, is heard for a quarter of a mile, in a round, and that in articulate words, and these hanging in every little portion of the air, and all in a space of time far less, perhaps, than a minute.

To inquire of the space of time in which sound is conveyed. It can be found thus. Let a man stand in a steeple by night; let another stand in the field, a mile off, perhaps, or as far as the bell can be heard, and let him have ready a torch lighted, but covered. Then let him in the steeple strike the bell then let the other, who stands in the plain, as soon as he hears it, lift the torch: in this way, by the space of time between the striking of the bell and the seeing of the torch, shall he that stands in the steeple discover the time of the motion of the sound.

In guns, the flame is seen sooner than the report is heard, although the flame follow the discharging of the ball; so as the flash issues later, but sooner strikes the sense. Whence it is rightly gathered, that the beams visible are more speedily diffused, and arrive, than the species or impres

sions of sound.

Of the Affinity, or Non-affinity, which Sound hath with the Motion, local and perceptible, of the

Air in which it is carried.

Sound doth not appear manifestly and actually to shake and trouble the air, as doth wind; but the motions of sound appear to be effected by spiritual species; for thus we must speak, until something more assured shall be found.

So as I conceive that a very loud sound of one shouting, at a little distance from the very motion of the breath, shall scarcely stir any trembling aspen leaf, or straw, or flame.

But in greater pulsations there is found a very bodily and actual motion of the air; but whether that proceed from the motion itself which generates sound, or from a collateral cause, or some concomitants, appeareth not. Thunder-claps sometimes make glass windows to tremble, and even walls: I think, also, that ordnance let off, or explosions of mines, do the same.

A word quietly uttered, which at a distance perhaps of thirty feet can be heard, will yet hardly stir the flame of a candle, that is held within a foot of the mouth; whilst blowing a little strongly with the mouth, shall make the flame to waver, at a much greater distance.

The sound of bells, and the like, comes louder, and goes off more dully, as the wind blows towards the ear, or against the sound. The same happens in a shout, which being uttered against the wind, is not heard so far.

It is delivered, that through vast shouts of numbers applauding and cries of rejoicing, the air has been so broken or rarefied, that birds flying over have fallen down. There runs an opinion that the noise of many bells ringing in populous cities is good against thunder and pestilence.

Some places and buildings are certainly reported to be so vaulted, that if one speak in them, and (as the report hath it) against the wall, in one part of the building, his words shall be better heard at some distance from the voice than close at hand.

I have observed, sitting in a coach with one side of the boot down, and the other up, that a beggar crying on the closed side of the coach hath seemed to cry on the open side; so as the voice was plainly repercussed, and went round, or at the least, whilst it sounded on all sides, it seemed to be heard on that side, on which it did best reach the sense.

If a candle be held to the wind-hole of a drum, and the drum be beat, the flame is shaken and extinguished. The same happens in winding of a hunter's horn, if the candle be brought near the mouth of the horn, &c.

Even the exquisite differences which sound takes, and carries them with it, show that these delicate affections are not continued local motions. For seals, in a matter fitly prepared, make exquisite impressions; so as in the generation of sound this same, perhaps, might happen. But the dilatation and continuance sort not, especially in liquids: but those exquisite differences we understand of articulate voices and musical tones.

But of this matter altogether (videlicet, what relation and correspondency sound has to the local motion of the air) let inquiry be more diligently made; not by the way, whether? (which sort of question in matters of this kind has ruined all,) but by the way, how far? and that not by arguments discursive, but by opposite experiments

And I remember, if I mistake not, that there and crucial instances.

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