Mikrokosmographia a description of the body of man. Together vvith the controuersies thereto belonging. Collected and translated out of all the best authors of anatomy, especially out of Gasper Bauhinus and Andreas Laurentius. By Helkiah Crooke Doctor of Physicke, physitian to His Maiestie, and his Highnesse professor in anatomy and chyrurgerie. Published by the Kings Maiesties especiall direction and warrant according to the first integrity, as it was originally written by the author.

CHAP. XXV. Of the manner of Hearing and of the Nature of Soundes.

COnsidering that to intreate of the manner of Hearing belongeth rather to a Phylosopher then to Anatomists, wee will be but briefe herein, yet somthing we thinke good to say because the structure of the eare was for the most part vnknowne to the Ancients.

The Eare is the instrument of Hearing, and the action of the Eare is the * 1.1 Sense of Hearing; vnto this Sense there are three thinges required: an Obiect, a Medium and an Instrument. The Obiect is that which is audible, that is, all Sounds. A Sound is a quality yssuing out of the Aire (Coiter addeth, or the Water) beaten by sudden and forcible collision or concurrence of hard and solid bodies, and those smooth, concauous and large. This definition we will labot to explaine in this following discourse. The Medium is ey∣ther Externall or Internall. The Externall Medium according to Aristotle is Ayre or Wa∣ter, but in water the Sound is but dull, as a man may perceiue when his head is vnder wa∣ter: yet they say that Fishes can heare in the water very well, as they can assure vs that vse in the night time to fish for Mullets. And although the water going into the water doe make a Sound; yet this Sound is made in the Aire and by the interposition therof, though it be made by the water.

The Internall Medium is the implanted Ayre concluded within the dennes or cauities of the Eares. The Instrument although we may say it is the whole inward eare furnished 3 1.2 with his cauities and other particles aboue expressed, and although that generally the Phi∣losophers and Physitians doe determine that the inbred Ayre is the especiall and proper Organ of Hearing; because as in the Eie the Chrystaline receiueth the Obiect, that is, the Light: so this in-bred ayre receiueth the Sound. Yet we are of opinion that not this ayre but the auditorie nerue is the principall instrument. For wee thinke with Galen, that not onely the alteration or Reception which is made by the in-bred ayre is the Sense of Hea∣ring, but also the dignotion or iudgement of that alteration. VVherefore Soundes and Voyces are transferred by this ayre to the Auditory nerue as vnto the substance that is ap∣prehensiue, and from thence to the common Sense where they are exquisitly iudged off. For if they must bee knowne and perceiued, then must they touch some substance indued with Sense, because all action is by contaction. Now the Sensatiue faculty is not trans∣ported out of the bodie, and therefore it was necessary that the Sound should apply it selfe to the Eare.

The Sound is generated of hard bodies mutually striking one another, as of the Effici∣ent cause, (for soft bodies doe easily yeeld, not resisting the force that is offered vnto them) * 1.3

and is receiued in the ayre as in his matter this Aire accompanieth the Sound, and carry∣eth it as it were on his wings; for as the ayre is mooued so also is the Sound carried as wee may perceiue by a ring of Belles farre off from vs: for when the winde bloweth towards vs we shall heare them very lowd again when the ayre is whiffed another way, the sound also of the bels wil be taken from vs. So also when two hard bodyes are smitten the one against the other, we see the purcussion before we heare the sound, for we do not heare the sound before the ayre that was moued do bring the sound with it to our eares, neither is that mo∣tion made in a moment but in time, and is carryed swifter or slower as the percussion of of the resisting bodyes was more or lesse vehement and quicke; (for this the Phylosopher requireth in sounds) and consequently the repercussion or repulse of the ayre. So wee see in a Drumme if the skin or Vellam be moist and laxe, either they will not sound at all, or they make but a dull noyse.

The Aer being affected with the quality of the sound driueth & altereth that ayre that is next it, and so by succession till the alterations come to the Ayre that is next to the * 1.4 outward Eare: euen as when a stone is cast into the water it stirreth vp circles which driue one the other till the water moueagainst the brinke, or if the water bee broade doe of it owne accord determine. In like manner by the percussion of the Ayre there are generated certaine circles which mooue one another till by succession they come to the Organ of hearing: which continuation of the Ayre thus beaten Auicen and the antient Anatomists call vndam vocalem, the vocall waue.

* 1.5 But if the stone be great and violently throwne into the water, so that it driueth the circles vehemently to the brimme of the pond, then will those circles be repelled againe and so runne doubled and hudling to the first circles. In like manner if we hallow or speake alowde against any arched place, or against a wood or a mountaine, the voyce will bee doubled and an eccho will answer vs.

But all ayre doth not alike receiue a sound. For a pure thin and cleere ayre, which is * 1.6 vehemently and suddainly strucken by two hard bodyes whose superficies is broad, will sooner receiue the sound, and represent it more smartly then if the Ayre or the bodyes bee not so prepared. A Needle strucke against a Needle will not make a sound though they bee hard bodyes, because their superficies is narrow and not broad, and so in the rest. But aboue all that Ayre which is contained in a concauous or hollow place, doth best receiue the species of soundes; because in the reflexion there are many percussions besides the first; for the reuerberation of the Ayre maketh much for the increasing of the sound, which we may see in dens, caues, woods, hollow mountaines, wels, and such like; which will not on∣ly returne againe the sounds that they receiue, but sometimes also the very articulated words. And thus much concerning the nature and generation of sounds, which is a meere Phylosophicall disquisition, and therefore we passe it ouer more briefly. Now let vs come to shew how the outward Ayre that is beaten, is communicated with the implanted Ayre and the internall parts.

But before we descend to this it shall not be amisse to let you take a view of the diuers opinions as well of the Antients as of the Moderne writers, concerning the manner how 1 1.7 hearing is made, for vpon that very point we now are.

The first is that of Empedocles, who thought that this sense of hearing is made because the Ayre offereth a kind of violence to the inward part of the Eare, for because the inward Eare is intorted like a winkle-shell, and hangeth as a bell in thee steeple of the body, it easi∣ly perceiueth all appulsions of the Ayre.

The second is that of Alcmeon, who thought that wee therefore heare because our 2 1.8 Eares are within empty, for all emptie things doe resound if the sound get into them.

The third is that of Diogenes, who saith, that in the head there is an Ayre which is 3 1.9 smitten by the voyce and so mooued: against whom Hippocrates writeth in his booke de car∣nibus, where he saith, that there are some Authours of Naturall Phylosophy, who affirme that the Braine yeeldeth a sound, which cannot be. For the braine it selfe is moist, now no moist thing will resound, but that onely which is drie.

The fourth is the opinion of Hippocrates in his booke de locis in homine. First of all 4 1.10 saith he the care is perforated, and in that part we heare, yet the emptie places about the eares doe heare nothing but a confused noyse, but that which entereth through the mem∣branes into the braine, that is distinctly heard; where there is a perforation through the

membrane which inuesteth the Braine. And in his booke de carnibus, we heare because the holes of our Eares reach vnto the dry and stony bone to which is added a canale or fistu∣lous cauity, against which hard bone the sounds do beate, and the hollow bone because of his hardnesse yeelds a reasonance. Now in the hole of Hearing neere that hard bone, there is a thin Filme like a Cobweb the driest of all the Membranes of the body: but that which is the driest is fittest to conceiue or receiue a sound as may be prooued by manie arguments. When this Membrane therefore yeeldes the greatest resonance then wee heare best.

The fift is Platoes opinion. The aire that is implanted in the eare is beaten, that pulsa∣tion is transmitted into the principall seate of the soule and so we heare. 5 1.11

The sixt is Aristotles. We heare (saith he) when the aire is mooued by two solid bo∣dies, 6 1.12 that which is beaten hath a plaine superficies that from thence the aire might re∣sult; the concussion of these two bodyes must be vehement, that the aire between them may not diffuse it selfe, but bee apprehended and smitten before his dissipation, for so onely the sound resulteth and filleth the aire by continuation euen to the eare. Now in the organ of Hearing there is a certaine implanted Aire. Hence it commeth that when the externall aire is mooued the internall receyueth therefrom a motion and agitation (which otherwise of it selfe is immoouable) so as it exactly perceyueth al the differences of the motion of the externall aire. Thus is the Hearing begunne and perfected in the Ayre.

Seauenthly, Galen in the sixt chapter of his eight Booke De vsu partium. It was neces∣sarie 7 1.13 (saith he) that from the Braine a certaine surcle should be propagated downwarde to the eares, which might receiue the sensible obiect comming from without, whether it were a voice or a sound made by the percussion of the aire; for the motion that is cau∣sed by such a percussion diffuseth it selfe like a storme of winde or raine, or like a waue of the Sea till it ascend vnto the Braine.

Thus far the Ancients, who most of them, if not all, were ignorant or at least much to seeke in the exact Anatomy of the Eye. Among the later writers Vesalius and his ad∣herents haue it thus. 8 1.14

A Nerue of the fift coniugation proceedeth through a torted and writhen passage, and extendeth it selfe into a Membrane where-with, the hoale of the eare is stopped, which Membrane being thin, dry, and well stretched & beaten by the outward aire ma∣keth a sound, being assisted by the hardnes of the bone and his turning gyrations much like the shell of a Snaile or Periwinkle.

Columbus. So also we heare by the help of a Nerue of the fift coniugation, which at the middle of the Labyrinth becommeth thicker, but yet maketh not the Membrane.

Messa saith, that the sound is made by the motion of the small bones, and thence we heare. 9 1.15

Volcherus Coiter. The outwarde Aire affected with the quality of the sounde run∣neth 10 1.16 vpon the Membrane or Head of the Drumme, which when it is beaten mooueth the small bones that are tyed to it. The bones strike the Nerue that runnes ouerthwart the Membrane. The same Nerue makes a repercussion vpon the Membrane, whence it is that the ayre included receyueth the alteration and the sound. The Sounds without any disturbance are carried through the contorted Meanders of the Eares to the Audi∣tory Nerue, which receyueth the Image of the noise, and presenteth it to the principall Sensator.

Laurentius hath almost the very same in substance. The outward aer (sayth he) being stri∣ken 11 1.17 by hard and solid bodies and affected with the quality of the sound, altreth the aire that is next vnto it, till by a continuation it come to the eares, where it first encountreth with the Membrane: the Membrane being strucken mooueth the three little bones and transmitteth in a moment the liuely Charracter of the sound, which Character is recey∣ued by the implanted aire, and through the windows it sendeth it through these croo∣ked and winding Labyrinths into the Snaile shel, from whence it arriueth at the audito∣ry Nerue, and from thence is conueyghed to the common Sense as vnto an equal iudge or Censor.

Archangelus hath it on this manner as neere as I can vnderstande him. The thing that 11 1.18 maketh the sound sealeth or stampeth in the ayre the species or forme of the sound, and withall driueth it on vnto the Instrument of hearing which is also aiery that it might bet∣ter

receiue those species, and must likewise be mooued; wherefore the hole of the Eare standing alwayes open (and in his inside supporting the stretched membrane of the Tympane, behinde which the aiery instrument of Hearing is concluded or shut vp, and to which the Anuile cleaueth) when the outwarde aire attaineth to that membrane the Hammer beateth vppon the Anuile, and so it commeth to passe necessarily that the In∣strument of Hearing (by which he vnderstandeth the implanted Ayre) it mooued vvith the same motion that the outward Aire is moued, whence it is that altogether the same species or similitude of sound mooueth the Faculty of hearing, which is brought thither by the outward aire. Nowe the Nerues of Hearing do determine into the same place where this aerie instrument of Hearing is concluded, and a membrane made of the am∣plification of these Nerues encompasseth that aery bodie, as the Opticke Nerues doe a∣riue at the Cristalline humour. And as the Opticke Nerues do conuay vpon the wings as it were of the Animall spirit from the place of the Common sense the Visiue Facultie to the Cristalline humor: so these Nerues from the same Common sense doe transport the Faculty of Hearing to the principal organ of Hearing, that there might be a percep∣tion made of audible things. And so the Hearing when it hath apprehended the sounde of an audible thing carrieth it to the Soule, and then the Reason or the intellectuall or sensatiue Soule comprehendeth and taketh knowledge of that which maketh the sound to be a Bell or a Drum, or any other thing.

Finally, Bauhine my Authour (I call him so often my authour to stoppe their mouths 13 1.19 who would think that I should arragate too much to my selfe if I shoulde not acknow∣ledge him from whom I haue taken most of this History) expresseth it on this manner. The outward Aire is an external Medium which being driuen and moued by the mutual percussion of two hard bodies and affected with the qualitie of the sound, carryeth the sound which resulteth from that percussion vnto the Eare. The sound passeth through the hole of hearing which is alwayes open vnto the Membrane of the Tympane which it mooueth.

That Membrane being mooued, the implanted or in-bred aire is also moued and re∣ceiueth the sound, or at least his Caracter or impression, and transporteth it out of the first cauity of the stony-bone thorough the hole of the Stirrop and the Ouall window to the other two cauities which we called the Labyrinth and the Snayle-shel. From thence it is conueighed to the auditorie Nerue and to the originall thereof, that is the Afterbrain and so to the common sense as vnto a Iudge that is able to determine of the differences of sounds.

And because the Auditory Nerues are ioyned in the Bridge of the After-brain from whence they proceed, therefore all sounds are apprehended in one comprehension, not in two though there be two eares, that is, two organes of Hearing. But least the Mem∣brane before mentioned should be driuen too much inward by the violence of the out∣ward aire when it is violently beaten, Nature prouided three small bones and Muscles as we haue shewed before to preuent that inconuenience.

The vse of the Sense of Hearing according to Aristotle in his Booke De sensu & sensili is to acquire or get knowledge and wisedome. For speech being an audible thing is the verie Cause of Learning. Againe by the Hearing things are signifyed to our selues, as by * 1.20 our voice and tongues we are able to signify any thing to another, as Aristotle hath well obserued in the end of his third booke De Anima.

And so much shall haue beene sufficient to haue spoken concerning the Sense of Hearing, wherein I finde that I haue great cause to entreate my Reader fauourablie to * 1.21 reade ouer this Discourse, and to pardon me if in some things I haue not so fully satisfi∣ed him; for there are some passages in my Author, wherein I haue bene intangled, part∣ly by the difficultie of the matter, partly by the fault of the Printer, for in such a case as this the least error may prooue a sufficient remora or obstacle to interrupt the course of a Discourse, but as neere as I could I haue followed their words, at least their meaning, if they vnderstood themselues, as of some of them I make much doubt.

Notes

• * 1.1

  Three things required to Sensation. Obiect, Definition of a Sound. Medium.
• 3 1.2

  3. Instrument.
• * 1.3

  How sound is made.
• * 1.4

  How the scūd attainerh to the Eare. A fit compa∣tision.
• * 1.5

  Vnda vocalis.
• * 1.6

  What Ayre is fittest to re∣ceine a sound
• 1 1.7

  Diuets opini∣ons of the manner of hearing. 1. Empedocles.
• 2 1.8

  2. Alcmeon.
• 3 1.9

  3. Diogenes.
• 4 1.10

  4. Hippocrates.
• 5 1.11

  5. Plato.
• 6 1.12

  6. Aristotle.
• 7 1.13

  7. Galen.
• 8 1.14

  8. Vesalius.
• 9 1.15

  9. Messa.
• 10 1.16

  10. Coiter
• 11 1.17

  11. Laurentius.
• 11 1.18

  11. Archangelus
• 13 1.19

  13. Bauhine.
• * 1.20

  The vseof the Hearing Aristotle.
• * 1.21

  A deprecatiō.