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. XIX. Of the Muscles of the inward Eare

THE Hammer beeing articulated to the Anuill with that kinde of articulation which we call Ginglymos, it followeth that their motion must be very obscure, now they are moued together with the membrane at which the Hammer han∣geth, vpward and downeward hauing one muscle appointed for this motion within the membrane, another seated without it.

The internall muscle [Table II. figu 2. 1] described first by Eustachius, and scituated in the stony bone, is exceeding small, there being in the whole body none lesser: and yet the frame thereof is so elegant as no muscle in the body may bee compared thereto. It ari∣seth in the Basis of the wedge-bone in that place where there is a hole made with a root of the processe of the stony bone, and an additament of the nowle-bone.

It taketh his originall from a substaunce much like a Ligament. Afterward it becom∣meth fleshy, and groweth a little broader euen to the verie middest. Afterward it is againe angustated or straightned and produceth, Eustachius sayth but one Tendon. Whome Coiter and Aquapendens do follow. But Placentinus & according to him Bauhine say, they are two, very small, [Table II. fig. 5. below i] one of which is inserted into the vpper processe of the Hammer, the other into the necke thereof. But in Dogges a little before the insertion it hath a fleshy and round glandule a little depressed, which is not fixed to the membrane lest if it were drawne by it selfe being very small it should be in danger of breaking.

This muscle when it worketh draweth the head of the Hammer obliquely forward, and inward deduceth or inclineth it from the Anuill, and bending the processe of the Hammer driueth the membrane outward.

That this is the vse of this muscle Arantius proueth by an experiment on this manner. If, sayth he, in a greene head that is well dissected till you come to this part, you drawe this muscle with a sharpe hooke toward his originall you shall finde it hath a double vse: one that the head of the Hammer will manifestly recede or depart from the Anuil and be lifted vp, the other that the membrane will be driuen outward.

Now this motion which is made in the eares although it seeme to bee voluntary, be∣cause it is accomplished by a muscle which is an instrument of voluntary motion; yet it can hardly be perceiued by our selues, yea wee heare whether wee will or no, the reason is be∣cause the muscle is so very smal.

Neither doe we want examples of many muscles which we know assuredly doe worke as well while we sleepe as while we wake, which yet wee cannot obserue in our selues, but their motion seemes to be without our consent, as we may instance in the muscles of Re∣spiration, of the eies, of the eie-lids, the bladder and the fundament. Yet in some men this motion is more euident, which also they can at their pleasure moue or containe. The truth of this Aquapendens proueth on this manner. The motion sayth he is Sensible, and with a kinde of noyse, as if a man should stretch three threds a little distant one from another, and strike them with a Cittern quill as we do strike an instrument; or as if a man should scratch

ouerthwart the graine of a wansecoate, or imagine it to bee like the noise that the Steele makes when you strike fire out of the Flint. This motion is especially perceyued vvhen a man begins to yawne, but in the beginning of it we heare a kinde of obscure or dull sound from the commotion of the aire, much like the noise that a staffe makes when it is beaten against the aire. But this motion or noise in the aire many men do not obserue, neyther doth it seeme to me saith Placentinus, to haue any vse or to conferre at all to the Sense of Hearing; for if there be a noise in the aire and at the same time a man shall striue to stirre vp this motion, he shall heare the outward noise more imperfectly: And therefore this motion seemeth to happen either from the necessity of the matter, the Muscles necessari∣ly following the attrition of the Hammer against the Anuile, or else it was ordained by na∣ture for the auoyding of vapours. For in Agues wherein many vapors do arise vnto the head this noise is frequently heard, which wee conceiue to be when as the vapours which fill the cauity of the eares are by this motion dislodged, and yet we may vnderstande that this motion is not altogether at our owne disposition.

In like manner saith Bauhine when the Eares are purged into the mouth by the passage that way opened, I am woont to perceiue in my selfe a kind of tickling within my mouth neere the roote of the Vuula, at which time if I often swallow my spittle, I doe manifestly perceiue by the noise that that motion is ordinarily stirred vppe in mine eares: and I per∣ceiue likewise the foresaide tickling to bee appeased when the matter by that meanes is sooner purged into my mouth.

But how commeth it to passe that this motion is perceiued in both the ears at once? It may bee answered, that it happeneth in the eare as it dooth in the eye: for vvhen one eye is mooued, the other also instantly accompanieth it, as wee haue shewed before. A man would imagine that in large bodyed creatures this Muscle might be better perceiued then in a man. But we find it farre otherwise; for although beasts haue it, yet for the most part it is in them lesse and harder to finde then in a man.

Hee that is desirous to finde out this Muscle, must lightlie cut the Stonie process•• thoroughout the length, guiding his Knife by a Line which runneth there through but not very high, beginning at that part of the processe which is next vnto the Wedge∣bone, for the muscle runnes length-wise and so determines into the membrane of the Tympane.

The other Muscle [Table 11. figure 1 and whose insertion is at^b] is situated with∣out the membrane of the Tympane in the vpper part of the hole of Hearing about the middest thereof. Concerning the inuention thereof two excellent Anatomists of Pa∣dua in Italy doe contend. For Hieronymus Fabritius ab Aquapendente, whome therefore we call Aquapendens affirmeth, that he found it in the yeare 1599. But Iulius Casserius Pla∣centinus auoucheth, that he obserued it the seauenth day of March, in the yeare one thou∣sand fiue hundred ninety three. But out of question they both haue deserued wonde∣rous well of this Art which of them soeuer was the first inuenter thereof.

And because, sayth Bauhine, I would haue the world know how much I esteem them both, I will set downe both their descriptions thereof beginning with Aquapendens, bee∣cause he is the Ancienter, not to derogate from the other, seeing I loue and honor them both. The one was my maister in the yeares one thousand fiue hundred seuenty seuen, one thousand fiue hundred seuenty eight, and one thousand fiue hundred seauentie nine: the other in the yeare one thousand fiue hundred seuenty nine was my friend and fellow-Studient, and this friendship to this day we maintaine by entercourse of Letters, and shall do I doubt not so long as we liue. Aquapendens therefore hath it thus.

Furthermore, this yeare 1599. I found a muscle in the hole of hearing, cald 〈 in non-Latin alphabet 〉〈 in non-Latin alphabet 〉 [Tab. 10. fig. 9] which is without the membrane very small, fleshy and not without a tendon which proceedeth directly from the midst of that hole or passage, till it be inserted into the very center almost of the membrane on the outside iust against the place where the Ham∣mer on the inside is fastened to the membrane, which together with the Hammer it draw∣eth outward. You shall finde this newe muscle if in a greene head you cut the vtter Shell of the Bone which maketh the Hole of Hearing on both sides, which you may best do with a Chizell and a Mallet and so remooue the bone carefully to the sides, for so the Muscle will appeare, and yet I haue not bene able to finde it in all my latter dissections, although I esteeme the necessity of it to be so great that I thinke it was rather the fault of my dilli∣gence then a defect in Nature. Thus farre Aquapendens.

Placentinus describeth it on this manner.

In a man there is another Muscle situated in the vpper part of the hole of Hearing, [Tab. 11. fig. 1, ^{a b}] about the middest whereof the skinne and the Membrane which be∣ing implicated or folded together do inuest the saide hole, do euidently degenerate for the forming of this Muscle into a fleshy body: but almost membranous, distinguished or lined through with Fibres, hauing also a Tendon. The Figure of the muscle is round and in the progresse groweth slenderer by degrees, and so passeth directly on vnto the Tympane. It is inserted not into the outside of the Membrane nere the center; but the Tendon (which it transmitteth with a double extremity or termination into the cauitie of the stony-bone betwixt the Tympane and that part of the temple-bone from vvhich the bonie ring proceedeth) is fastened on the inside into the heade of the Hammer, be∣twixt the vpper and the lower processes thereof. The inuention of this Muscle if I attri∣bute to my selfe I shall not defraud any man of his due commendation, for I obserued it the seuenth of March in the yeare 1593. in the presence, &c. Thus far Placentinus.

The vse as well of the Internall as of this externall Muscle Aquapendens thus expres∣seth.

The vse of these Muscles is for the securitie of the Membrane, for because it might haue bene broken or torne either on the inside or the out, Nature prouided a strength

[illustration]

Table 11. Sheweth the Muscles placed in the cauity of the eares, with some other cauities and bones of the eares.

[illustration]

TABVLA. XI.

[illustration]

FIG. I.

[illustration]

FIG. II.

[illustration]

III

[illustration]

IV

[illustration]

V

[illustration]

VI

[illustration]

VII.

[illustration]

IIX

[illustration]

IX

• a, b. The externall Muscle whose insertion is at b.
• c. The Hammer of the Tympane couered with the Membrane.
• d. The membrane of the Tympane.
• e. The bony Circle.
• f. The bone called Mastoides.
• g. The Temple bone.
• h. The circle of the first cauitie.
• i. The internal muscle whose bifurcated ten∣don is shewne in the fift figure.
• KK. A portion of the Pericranium or scul-skin going vnder the bony Circle, making the membrane of the Tympane or Drumme.
• l. The Hammer lying vnder the membrane.
• m. The Anuile.
• n. The breach of the bonye circle at e vvhere the beginning and termination of it is.
• o. A part of the yoake bone.
• p. A part of the bone called Basillare.
• q, r. The first cauity.
• s. The Stirrop.
• tt. The Circumference of the Shell called Concha.
• u. A protuberation or swelling in the middle of the Cauity.

or defence in both places. For on the outside the aire beeing violently mooued might haue broken the membrane by thrusting it inward, and on the inside by beating it out∣ward; in the outside the externall aire which with violence togither with the sound ru∣sheth into the eare; on the inside the aire which thorow the mouth getteth into the eare doth forcibly sometimes driue the membrane from within outwarde; and in this man∣ner is the membrane stretched ordinarily in yawnings, blowings of the nose, retention of the breath, strong contentions, lowd voices, the excretion of excrements, and such like violent constraints. The externall Muscle therefore when the Membrane is driuen inward draweth it backe, and as it were recalleth it into the right place. In like manner, the internall Muscle retracteth it inward when it is turned or driuen outward. And these are the necessities for the satisfaction whereof Nature ordained these two elegant mus∣cles, to wit, for the preseruation of the Membrane.

The reason why the custodie of the Membrane was committed to a Muscle, that is, to an instrument of voluntary motion is rendred on this maner. If any other tie but that of a Muscle had bene made the Custos or Vindex of this Muscle, such a tie must haue held it alwayes stretched or tentred alike, and so the Membrane would rather haue bene more endangred then any whit secured. Besides, it was verie necessarie that as the impulsions of the aire vnto the Membrane are diuers, so there should be a varietie of power in that that was to curbe or limmit those diuers motions or impulsions. Such a varietie of power cannot bee imagined to bee in anie Ligament but onely in Muscles which make their operation with a certaine Analogie or proportion to the finall end which Nature entends, or according to measure; contracting and relaxing themselues more or lesse as neede shall be, accommodating their motion diuersly according to the diuers impulsi∣ons of the aire; for they suffer the Membrane onely so to receiue the offered violence, that neither the violence might be altogethet withstood but that the membrane might yeeld therto, nor yet the Membrane be outraged by such violence. In a word, these mus∣cles partly by yeelding and giuing groūd, partly by obluctation or opposition do secure the Membrane from being torne and rent asunder. Thus far Aquapendens.

Placentinus thus. The Muscles of the inward eare doe one of them assist the Ham∣mer against internall impulsions, the other against externall. The outward muscle which I founde out, that sendeth his Tendon into the cauitie of the Stony bone and ioyneth it selfe with the greater processe of the Hammer, draweth that part of the Hammer out∣ward which inclineth inward, and so moderateth the compression thereof made vppon the Anuile, that it is a defence against the internall Muscle.

The Internall which ariseth from the Wedge-bone and passeth into the cauity of the Stony-bone vnto the Head of the Hammer into which it is inserted, succoureth the same against the former when it is driuen inward, defining and limiting his introcession. For when the Tympane by an irruption of outward ayre, is together with the Hammer driuen inwarde, this muscle resisteth their motion that the Tympane and the Hammer should not be constrained beyond their Tether & so suffer laceration. Thus farre Pla∣centinus.

Varolius concerning this matter (for we account him also among our classicke authors, especially concerning the head) writeth on this manner.

Although, saith he, the sound do mooue the Sense of Hearing whither wee will or no, yet there is in vs a kinde of voluntary Animadversion which wee exercise in all our sen∣ses at our owne pleasure when we would iudge curiously of any sensible thing. Wherefore as by the helpe of the muscles of the eye men do voluntarily direct the center of the Cri∣stalline toward the obiect which they attentiuely behold, so within the organ of Hearing there is placed a small muscle, which arising from the fore-part is inserted into the articu∣lation of the triangle (so he calleth the Stirrop) with the Anuil: when this muscle is contra∣cted, the Triangle or Stirrop is drawne a little forwarde, the ioynt of the Anuile vvith the Hammer yeelding thereto, and approacheth more directly to the Center of the Tympa∣ne, and at that time we heare with more attention and better iudgement, like as wee are able to see the least visible obiect when we stedfastly beholde it by a line concentricall to the Horny Membrane, the Pupilla and the Cristalline humor. Some haue imagined that the small bones of the cares diuersly mooued by this muscle, doe make within the organe of Hearing many and different sorts of sounds, whose opinion we thinke sufficiently confuted by the former assignation which we made of the vse of the muscle. Thus farre Varolius.

Notes

• The internall muscle.
• His originall and progresse
• The vse of it according to Arantius.
• Aquapendens his demonstra¦tion of the motion of the muscle.
• Bauhines de∣monstration thereof out of the experiēce in himselfe.
• It is lesse in great Beastes then in men.
• How to finde this Muscle.
• The other Muscle with∣out the mem∣brane.
• Bauhins hono∣rable remem∣brance of A∣quapendens & Placentinus.
• Aquapendens his descriptiō of this muscle.
• Placentinus de¦scription.
• Aquapendens his opinion of the vse of the Muscles.
• Placentinus opinion of the vse of the muscles.
• Varolius his vse of a mus∣cle in the ear.