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pipe being of a double length, and continued in | ness; and let this be distinctly inquired, not only one; Jet two together play the same tune at either whether they hear any sound at all from above. end, and let it be noted whether the sound be con- which is made in the air, but also, whether they fused, or amplified, or dulled.

hear the percussion of the body of the water Let there be two hollow trunks taken, and within the water, where no air is. I have made joined together crosswise, so as they shall open this trial in a bath ; a pail of a good size with the the one into the other, in the place where they are mouth turned over was, in such wise, pressed joined; and let two speak into the direct and evenly down, as it carried the air fairly down transverse trunk, and let the ears of two be in with it, in its hollow, below the water, to the like manner applied to the opposite ends, and depth of a hand-breath; and in this manner the observe whether the voices confuse one another. pail was held down with the hands, that it should

not overturn nor rise: then a diver put his head Of the accessary lids and Impediments of Sound; within the pail, and did speak : his voice was

of the Stay of Sound ; and the Diversity of heard, speaking; and even his speech was artiMediums.

culately distinguished, but wonderfully shrill, I remember in a chamber in Cambridge that and almost like a whistling, as the voice useth was something ruinous, that a pillar of iron was

to be heard in a play of puppets. erected for a prop, of the thickness perhaps of a

Let it be exactly inquired, so as it be clearly thumb's breadth and a half; and that this pillar, rendered positive whether sound can be generated, being struck with a stick or otherwise, made a except there be air betwixt the percussing and little flat noise in the chamber wherein the pillar the percussed body. As, if two pebbles hanging stood, but in the chamber beneath a resounding by a string be let down into a basin of water

, or boom.

a river, and shaken, so as they shall strike toTo inquire, which bodies, and of what solidity gether in the midst of the water; or let an open and thickness, altogether debar and shut out pair of tongs be thrust down into the water, and sound; as, also, which more or less dull, although there knapped; and let it be noted whether they they intercept it not wholly. For as yet is it not give a sound, and what. I do suppose that divers, known which mediums interposed be more propi- unless there may perchance be some, by the suc

in swimming, make no noise under the water ; tious, which more adverse. Therefore, let there be trial made in gold, stone, glass, cloth, water, cession of motion under the surface of the water, oil, and of the thickness of each. Hereof is all and the water thence striking the air. need to inquire further.

There is no doubt but in bladders tied, and not Air is the aptest, and, as it were, the sole me

quite full, and shaken, there is a sound given, dium of sound. Again, the moister air (I judge) namely, of the liqror contained in them, and no better conveyeth sound than the drier; but in a less a sound is given on letting down a stone fog what happeneth I remember not. Also, the

into water, when it strikes the bottom of the ves. night air better than by day; but this can be sel. But in the former trial air is intermingled; ascribed to the silence.

in the second, the percussion of the bottom of Inquire touching the medium of flame, what its the vessel by the stone communicates with the operation shall be in respect of sound; whether, air without the vessel. But, after the first perto wit, a flame of some thickness altogether stop diate through the whole area of the sphere dese

cussion, it needeth not that there be air intermeand intercept sound, or at least deaden it more than the air. This can be seen in bonfires.

rent; for that is shown by the trial of one speaking Also, to inquire concerning the medium of air in a pail under the water, where part of the defevehemently agitated. For, although wind

rent from the water is not air, but the wood of

carry sound, yet I deem that any vehement wind doth the pail, and the water; whence the sound is somewhat trouble sound, so as it shall be heard sharpened, and minished, and lost. less far, even with the wind, than in still weather,

But, because it is manifest that sound passes of which let there be more inquiry made.

through and penetrates hard bodies, (as potters' To see what sound brass or iron, red-hot, yields, earth and glass ;) and it is also most certain struck with a hammer, compared to that which (although hitherto concealed from men's obseril gives cold.

vation) that there is, in every tangible body, some pneumatical part, besides the gross parts inter

mixed, it is to be considered whether penetration of the Penetration of Sounds.

of sound of this kind come not thence, for that The aëtites, or eagle stone, hath like a kernel the pneumatical or aerial parts of the tangible or yolk of the stone, which being shaken makes body communicate with the outer air. a fat sound; so a hawk's bell, [stopped,] but Take a vessel of silver, and another of wood, a much clearer if there be a chink.

full of water ; take a pair of iron tongs, and knap Let inquiry be made of divers, if they hear at them in the water in the vessels, at the distance all under water, especially that is of any deep- of a thumb's breadth, perhaps, or more. from the



boltom: 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 : 80 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, It is, however, to be observed whether sounds that that sound by the throat is not effected unless proceeding from the greater pulsations of the air through the opening which lies between the (such as are made by the discharge of ordnance) throat and the nostrils.

become not more exile when they enter by those

small apertures; for it may be that the subtilties of the Carriage of Sounds, and their Direction or of sound shall enter unconfused, but the whole

Spreading; and of the Area which Sound fills, crash, or roar, not so well. together and severally.

The rays of visible bodies do not strike the All sound is diffused in a sphere from the place sense, unless they be conveyed through the meof the percussion, and fills the whole area of this dium in straight lines, and the interposition of sphere to a certain limit, upwards, downwards, any opaque, in a right line, intercepts the sight, sideways, and every way.

although every thing else be on all sides wholly Throughout this orb the sound is loudest close open. But sound, if there be a dilatation or pasto the stroke; thence, in the proportion of the sage, whether by arching over, or hy inverted distance, it grows more faint, until it vanishes. arching downwards, or laterally, or even by windThe limits of this sphere are extended some little ing, perishes not, but arrives. Nevertheless, I by reason of the quickness of hearing; yet is judge that sound is more strongly carried in there something uttermost, whither, to the most straight lines, betwixt the pulsations and the ear, delicate sense, sound reaches not.

and that by its archings and windings it is someThere is something, I think, in the direction of what broken; as, if there be a wall betwixt the the first impulsion; for, if a man should stand in speaker and the hearer, I think that the voice shall an open pulpit in the fields, and shout, the voice, not be so well heard as if the wall were away. I judge, should be further heard forwards from the I judge, too, that if the speaker or the hearer be speaker than behind. So, if ordnance, or a placed at a little distance from the wall, the voice harquebuss be discharged, I judge that the sound shall be better heard than nigh unto the wall, beshall be further heard before the ordnance or har- cause the arching so much the less departs from quebuss than behind it.

a right line. But this also would be further inWhether there be any thing in the ascension quired. of sound upwards, or in the descension of sound If the ear be laid to the one end of any tube or downwards, which may further sound, or make long hollow trunk, and a voice speak softly at the it cease nearer, doth not appear. The sound is other opening of the tube, such a voice shall be indeed well heard, if one speak from a high win- heard, which, being as softly spoken in the air at dow or turret, by those who stand upon the large, should not arrive, nor be heard. Whence ground; and, contrariwise, being uttered by those it is clear, that that confining of the air helps to that stand upon the ground from the window or the conveying of the voice, without confusion. turret, but by whether more easily, or further off, It is also a common opinion, that, other things let better inquiry be made.

being equal, the voice is better heard within doors Pulpits are used for speaking in assemblies, than abroad; but whether the voice be better and generals did usually speak standing upon heard when the ear is out of doors, and the voice mounds of sods; yet is it is no wise hence con- within the house; or contrariwise, when the voice firmed that sound easilier descends than it rises, is out of doors, and the ear within the house, may since the cause hereof may be the liberty of the be further inquired ; albeit herein also the opinion air in the higher place, not thronged or hindered, is received, that what is abroad is better heard as below amongst the crowd, but not the readier within doors, than what is within, abroad. motion downwards. Therefore, let, not the con- It is common to hearing and sight, and, indeed, templation stay in this instance, but lei 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 diTlic 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.

and the Instruments ; and of the Species of Sounds are not carried so far, articulate and

Sounds which occur. distinct, as their species, and a confused coil of them; for the hum of voices can be heard where The kinds of sounds appear to receive such a the articulate words themselves are not heard ; division: loud, soft, sharp or treble, base; musiand a confused tinkling of music, when the har- cal, unmusical; interior or whispering, exterior mony itself or tune is not heard.

or sounding; simple, compounded, original, reSound is preserved, at the best, in a hollow flected; so as they are divisions six. trunk. Therefore let there be taken a hollow The stronger the first pulsation shall be, and trunk of a good length, and let it be put out from the dilatation the more free, and without let, the the window of a lower chamber; let one speak greater is the sound given : the weaker the perby thrusting of his head out of the window, at cussion, and more disturbed the dilatation, the less. one end of the trunk, as softly as ever he may: Treble sounds are carried as far, and perchance let another lay his ear to the other end of the farther than base. Let this be better inquired. trunk, standing below upon the ground : let this Accordingly as the concave of a bell shall be be done in like wise reversely, by speaking from greater, it giveth a baser sound; the less, the below, and laying to of the ear above, and from more treble. this trial let a judgment be made, whether the The bigger a string, the baser sound it shall voice ascend or descend more easily, or even yield ; the less, the more treble. alike. They deliver for certain, that there be A string, the niore tightly strained, the more some places and buildings so vaulted, that if one treble sound shall it yield; the looser, the baser: stand in a certain part of the chamber, and speak, so as a little bigger string more tightly strained, he can be better heard at some distance than near. and a less more slackly, shall give the same note.

All harmony appeareth to sound somewhat In trumpets, in like wise, in flutes, horns, and fuller and deeper at a little remoteness from the recorders, pipes, also in the mouth of a man place of the sound than near; so as something whistling, the more narrow and straight they should seem to happen to hearing about sound, are, they give the more treble sound; the wider, like as happeneth to sight about visible species, or more open, the baser. that some removal from the organ of the sense In flutes, the air, issuing by a hole nearer the furthereth the perception of the sense. But in breath, yields a more treble sound; by one more that opinion may be twofold error. First, because distant, a baser: so a little bigger flute by the in the act of sight there be, perhaps, beams re- nearer hole, and a smaller by the more removed, quired from the object to the pupil, which there may give the same note. 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 kind gers 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; If a drinking-cup of glass or silver he taken and forasmuch as, in the removing of cataracts of the fillipped, if the water stand higher in the cup, and eyes, the little silver needle wherewith the cata- the cup be fuller, it will give a more treble sound; racts are removed, even when it moveth upon the if lower, and the cup be more empty, a baser. pupil within the coat of the eye, is excellently In a hollow pipe, such as they use for shoot

ing of birds, if one whistle with the mouth, In objects of sight, if the eye be placed in the setting the mouth to one end of the tube, the dark, and the object in the light, it shall do well; sound is dulled, truly, to the bystander; but if but if the object be placed in the dark, and the the ear be laid to the other end, it gives a most eye in the light, you shall not see. So, if a thin sharp sound, so as it shall hardly be borne. veil or net-work be cast over the eyes, the object Let there be a trial made with a trunk, in the is well seen ; if upon the object, it confounds part where the ear is laid, narrow, in the part sight. And albeit, that perhaps neither of these where the mouth is set, wider, and conversely; agreeth to sound and hearing, yet ray they ad- whether the sound be rendered more treble or vertise us that trials be made, whether the ear baser, after the manner of mirrors, which contract ret against the hollow trunk, if the sound be or enlarge the objects of sight. inade at a distance in the air at large, or conversely, the sound be produced at the hollow of the Mulliprication, Majoration, Diminution, trunk, the ear being placed at a distance in the

and Fraclion of Sound. air at large, favour more the perception of the It would be seen in what, how, way, manner, sense.

sound can be artificially magnified and multiplied.





Mirrors do effect both in sight. Now, the sud

of the Repercussion of Sounds and Echo. den reflection of sound seems to turn to augmentation; for if the voice and echo be yielded

The repercussion of sounds (which we call ingether, need is that the sound be not distin- echo) can be taken for an argument that sound

is not a local motion of the air; for if it were, the guished, but magnified. Therefore, sounds upon repercussion should be made in manner conformarivers are greater, the water resounding and blending itself with the original sound.

ble to the original, as happens in all corporeal I have also noted that when a round-house is repercussions. But in sound, wherein such an made in water-conduits, then a long vault, and exact generation is required, as in the voice, then a greater chamber, (such as is to be seen in which hath so many organs, and in musical inthe fields by Charing Cross near London,) if you which yield the repercussed sound have nothing

struments, which be curiously framed, the things cry at the window or slit of the round-house, and one stand by the window of the greater chamber, such, but are merely rude, having almost nothing a far more fearful roaring is heard than by one

save this, that sound passes not through them. standing where the cry is made. I bethink ine that in the play of puppets, the

of the Consents and Dissents of Audibles and speaking is such as it is heard distinctly, but far Visibles, and of other so called Spiritual Species. sharper and more exile than in the air at large; as happens in mirrors that render letters far smaller

They agree in these : than they are in the ordinary medium : 80 as

Both are diffused in a spherical compass or orb, sound appears plainly possible by art to be both and fill the whole area of that sphere, and are amplified and rendered more exile.

carried to very distant spaces, and wax faint by Children hold the horn of a bent bow betwixt degrees, according to the distance of the object, their teeth, and with an arrow strike the string, then vanish. Both carry their figurations and whence is produced a more resounding sound, and differences into minute portions of their orb, ena far greater boom, than if the bow were not held tire and unconfused, so as they are perceived in the teeth ; which they ascribe to the consent through small crannies no otherwise than in an which the bones of the teeth have with the bone open place. of hearing; since, conversely also, by a certain Both are of exceedingly sudden and swift harsh sound in the hearing, the teeth too be set generation and dilatation, and conversely they are on edge.

extinguished, and perish suddenly and quickly. In like manner, let a lance touch the wood of Both take and convey minute and exquisite the belly of an harp, especially of the hole in it differences, as of colours, figures, motions, disat the hollow end, and be held with the teeth at tances, in visibles; of articulate voices, of musical the other end, and the harp struck; the sound is tones, and of their swift changes and trepidation, made greater by taking hold with the teeth, that in audibles. is to say, to him that so taketh hold.

Both, in their virtue and force, appear neither It is most assured (however unnoted) that the to emit any corporeal substance into their meforce, which after the first percussion carries on diums or their orb, nor even to give forth or proballs, or arrows, or darts, and the like, is situated voke a local perceptible motion in their mediums, in the minute parts of the body discharged, and but to convey certain spiritual species, of which not in the air continually carrying it, like a boat the nature and manner is unknown. in the water. This being premised, it may be Both appear to be not generative of any uther considered whether sound might not be lessened virtue or quality besides their proper virtue, and so in ordnance or a harquebuss, without much far to work, being else barren. weakening of the percussion, in this manner. Both in their proper action appear, as if corpoLet there be a harquebuss made with a barrel of really, to work three things. The first, that the a pretty strength, so as it break not easily; in stronger object drowns and confounds the weaker; the barrel let there be four or five holes made, not as the light of the sun, the light of a candle, the like chinks, but round, about the middle of the report of ordnance, the voice. The second, that barrel. The percussion hath already gotten its the more excellent object destroys the weaker force, excepting so far as by reason of the length sense; as the light of the sun, the eye, a violent of the barrel it may be increased; but the percus- sound close at the ear, the hearing. The third, thai sion of the air at the mouth of the harquebuss, both are repercussed, as in mirrors and the echo. which generates the sound, will be much at- Neither doth the object of the one confound or tenuated by the emission of sound through those hinder the object of the other; as light or colonr, holes in the middle of the barrel, before that the sound, or contrariwise. air enclosed arrive at the mouth of the harque- Both affect the sense in animals, and that by buss. Therefore it is probable that the sound and objects in greater or less degrees grateful on boom shall by many parts be diminished. odious: but they affect also after their own mar




ner inanimates proportionate, and having (as | cured of cataracts of the eyes, when the little si!seemeth) a conformity with the organs of the ver needle moved over the very pupil of his eye, senses; as colours, a mirror, that is crystalline and did touch it, he, without any medium, (that like the eye; sounds, the places of reverberation, silver needle being far narrower than the pupil which seem, likewise, to resemble the bone and itself of the eye,) saw perfectly the needle. The cavern of the ear.

second, that the cave of the ear is distinctly interBoth work diversely, accordingly as they have posed before the organ of hearing, so as, being their mediums well or ill disposed.

without, the sound is altogether unable to touch To both the medium the most conducible and the bone and membrane of hearing. propitious is the air. In both the stretching of The species of sight are more swiftly conveyed the sense, and, as it were, its erection to perceiv- than sounds, as appeareth in the flash and report ing, availeth somewhat in more nice objects. of guns; also in lightning and thunder, where

the thunder is heard after a while. They differ in these :

I conceive also that the species of sound do The species of visibles appear to be as if emis- hang longer in the air than visibles. For, although sions of beams from the visible body, almost like neither do these perish on the instant, as we see odours. But the species of audibles appear more in a ring spinning, and lute-strings fillipped, and to partake of a local motion, like the percussions in twilight and the like; yet 1 deem that sounds, which are made in the air: that whereas bodies for that they are carried by the wind, stay for the most part work in two manners, by com- longer. munication of their nature, or by an impression or The beams of light being gathered, induce heat signature of their motion, that diffusion in visibles also, which is an action diverse from the visible appeareth more to partake of the former manner; quality. In like manner, if it be true that shouts in audibles, of the latter.

have cast down birds flying over, that is also an The dilatation of sounds appears to be more evi- action exceedingly diverse from the audible dently carried by the air than of visibles. For i quality. judge that a vehement wind shall not so much There seemeth not in visibles to be found an hinder any visible afar off, as a sound; I under- object as odious, and noisome to the sense, as in stand the wind blowing contrary.

audibles; but they affect it more evenly; for It is a notable difference, whence also many things foul to sight rather offend by moving of the less differences flow, that visibles (original light fancy concerning foul things than of themselves; excepted) are not carried but by right lines, but in audibles the grating of a saw that is sharpwhilst sounds are carried by arcuate lines. ened, and other like sounds, cause a horror; and

Hence it happens, that visibles confound not a discordant note in music is straightways reone another, that are represented together : sounds fused and loathed, contrarily. Hence it happens, that the solidity It is not assured, that there is refraction in of the substance seems not greatly to hinder sight, sounds, as in beams. But, donbtless, sounds do provided only the positions of the parts of the rebound: but that is to be ascribed to reflection, body be after a simple order and with straight For, I do not think, if sounds pass through passages, as in glass, water, crystal, diamond; diverse mediums, as air, cloth, wood, that there but a little silk or linen cloth breaks the sight, be one place of the sound, where it is carried, anthough they be bodies very thin and porous; but other where it is heard, which is the property of cloths of this kind little or nothing hinder hearing, refraction; but refraction seems to depend upon which those solids do exceedingly. Hence it action, in right lines, which pertains not to sound. happens, that unto the reverberation of visibles a But contraction of sound, and its dilatation, acsmall mirror suffices, or like transpicuous body, cording to the disposition of the medium, happens, let it be only placed in a right line, where the undoubtedly, as in the speaking of puppets, and visibles pass; but unto making of the reverbera- under water: the sound is contracted within that tion of echo, it needeth also to confine the sound cell, which abroad is dispersed; as by mirrors from the side, because it is earried to all sides. visibles are dilated and contracted. T'he visible object is further carried, in proportion, A tremulous medium (as smoke in vişibles) than sound.

makes the visible objects also to tremble; but in Visibles, too nearly approached to the eye, are sounds nothing such is yet found, unless, pernot so well seen as at some little distance, so as the chance, the rise and fall by winds.

For the beams may meet in a more acute angle; but in trembling in the nightingale-pipe is trembling of hearing, the nearer the better. But herein there the percussion, not of the medium. may be twofold error. The first, because to see- Going from great light into the dark, or out of ing there is required light; but if the object be the dark into the light, the sight is some little brought rery near to the eye, this is shut out. confused; but whether the like be after very loud For I have heard of one trustworthy, which was noises, or a great silence, would be inquired.

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