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. XXI. Of Nerues in Generall.

AS the Naturall Faculty together with the Bloud and the thicker Spirit is deriued through the Veines; the Vitall with Bloud and a thinner Spirite through the Arteries as through Canales and Water-courses into all the partes of the body: so the Animall Faculties, that is, of Sense and Motion are conuayed into those parts which are capable thereof with a subtle and fine Spirite a∣long by the Nerues as it were by the strings of an Instrument.

The Natures, Vses and Diuisions of the Veines and Arteries wee haue vnfoulded in the two former parts of this Booke, and are come in this place to the structure, differences and diuarications of the Nerues.

The Grecians call Nerues 〈 in non-Latin alphabet 〉〈 in non-Latin alphabet 〉, the acception of which words among the Phi∣sitians * 1.1 is manifould. Erotianus thinketh that Hippocrates vsed the word 〈 in non-Latin alphabet 〉〈 in non-Latin alphabet 〉 for all sortes of vessels, Veines, Arteries and Nerues. Galen in his first Booke de motu musculorum, in the beginning of his Booke de ossibus and in many other places, maketh three kindes of Nerues which appeare without bloud and without any hollownes.

Of these Nerues some proceede out of Bones, others out of Muscles, others are de∣riued from the Brayne and the spinall Marrow. Those which yssue out of the Bones & their protuberations are called 〈 in non-Latin alphabet 〉〈 in non-Latin alphabet 〉, Vincula, Tyes, Bands or Ligaments. Of these we shall heare particularly in the next Booke. Those Nerues that yssue out of Muscles are parts of the Muscles, and are called 〈 in non-Latin alphabet 〉〈 in non-Latin alphabet 〉, that is, neruous propagations and Tendons.

Now a Tendon is nothing else but an excressence or out-growing of the Fibres of a Ligament and a Nerue, which being sprinkled through the flesh doe meete together as it were in one Chord, by which chord the loynts are ledde according to the good plea∣sure

of our will. The third kinde of Nerues are those which the Phisitians doe properly call 〈 in non-Latin alphabet 〉〈 in non-Latin alphabet 〉, and that from their office; 〈 in non-Latin alphabet 〉〈 in non-Latin alphabet 〉 because they doe nutare siue flectere, that is incline or bend, and 〈 in non-Latin alphabet 〉〈 in non-Latin alphabet 〉 because they doe Tendere, that is, stretch. These Nerues do arise from the Brayne and the spinall Marrow, and are called by Galen organa 〈 in non-Latin alphabet 〉〈 in non-Latin alphabet 〉, In∣struments of Sense and voluntary Motion, because by them the animal Faculty and those that mooue within, that is, the impetuous spirites, are conuayed as it were by strings or chords into the particular parts. Auicen cals them Latores, cadgers in our language. Of these Hippocrates wrote in his Booke de locis in homine, The whole body is full of Nerues, that is, throughout the whole body the Nerues doe run from the Braine and the Spinall Mar∣row, and in his Book de arte he calleth them meteors in the flesh, because they are sprink∣led through the flesh, that is, through the Muscles.

Galen in his first Book de motu musculorum, compareth these three kinde of Nerues among themselues on this manner, A Ligament is insensible, a voluntary nerue of most * 1.2 exquisite Sense, and a Tendon of a middle nature, not altogether insensible, because it hath some filaments or strings of Nerues therein, neyther yet of so quicke a Sense as is a Nerue.

There are also many other parts in the body, which because of the similitude betwixt them and Nerues are called neruous, although they cannot bee referred to any of these three kinds: so we say the wombe, the bladder and the guts are neruous, as also the vre∣ters, the passages of the choller, and the eiaculatory vesselles. In this place we take the * 1.3 name of a Nerue properly for an organ by which the animall spirit and the faculty flow∣eth into the whole body. The nature of this organ may thus be described.

It is a common Instrument of the body like a Chord, white, round and long with∣out any cauity which our sense can discerne (vnlesse it bee the Optickes) but porous, in some vnited, in the greater nerue made vp of many small strings, & carrying as a Canale and motion which are conducted by the animall spirit from the Braine and the Marrow thereof vnto those parts of the body which are capeable of sense and motion.

Their substance is white and marrowy, much like the marrow of the braine, from which * 1.4 they take their originall (for I account the marrow of the Braine and the backe to bee of one and the same substance) but more compact and faster, for it was necessary the braine should be very soft because it was to receiue the species or formes of sensible things. So that by how much the nerue descendeth lower or is more separated from the brain, by so much doth it become the harder, that it might be better able to endure outward iniuries.

They are inuested with a double membrane, produced from the two Meninges or * 1.5 Membranes of the braine, the vtter whereof is the thicker produced from the dura mater whose office is to safegard and defend the marrow of the Nerue, and if it consist of many small chords or threds it ioyneth them altogether, and when it hath encompassed them about it receiueth into it branches from the neighbour-veines.

The inner membrane is thinner by much, and lyeth next vnto the marrowe or sub∣stance of the Nerue. It ariseth from the pia Mater and hath the exquisite sense of touch∣ing, which saith Fernelius it communicateth to the parts whereinto the nerue is inserted; * 1.6 for as the Braine is couered with these two membranes, so also are the nerues through∣out the whole body, a nerue being nothing else indeede but a production of the Braine. But this threefold substance of a nerue, as Falopius hath it in his obseruations and out of him Bauhine, may better be distinguished by reason then by sense, for Anatomy is not a∣ble to shew the difference betwixt the harde and soft membranes of any nerue except it be the optickes.

The substaunce which is in the middest or in the center of the nerue is the principall part thereof and performeth the action, for the sensatiue and motiue faculty is conuayed from the Braine vnto the parts, not by the coates but by the marrow. Hence it is saith * 1.7 Galen that if you cut asunder the marrow of a nerue, presently the part into which that nerue is inserted is depriued of sense and motion; as for the membranes they do the same office vnto the nerue which they did to the Braine, for the nerues are not properlie the instruments of sense and motion (for the immediate organ of motion is a Muscle) but they are like pipes by which the whole sensatiue soule and the faculties thereof both of sense and motion are led by the guidance of the Animall spirit from the Brayne vnto the parts of the body as they stand in neede either of sense and motion, or therefore the Physitians do vse to call them the organs of sense and motion. For they communicate

vnto those parts into which they are inserted either sense alone, or onely motion, or both together, for no part hath sense or voluntary motion without a nerue; & if the nerue that belongeth to any part be compressed, or intercepted, or cut asunder, or corrupted, the sense and motion of that part doth sodainly perish.

Hence it is as Aristotle also remembreth in his third Booke de Historia Animalium, that * 1.8 no part of the body hath any stupor or dulnesse, any palsie or resolution, any spasme or convulsion that hath not a Nerue in it. Now stupor is a diminution of sense, the palsie a priuation of sense and motion, and a Convulsion is a motion involuntary or against our willes.

Galen in the third and fift chapters of his sixteenth Booke de vsu partium sayeth, that * 1.9 those nerues which were made for voluntary motion are hard, and those that were made for sense are soft: and that the softe nerues do make for sensation and the hard for moti∣on, nay he goeth further in the eight chapter of his 7 booke de Administrationib. Anatom. and affirmeth that the soft Nerues are onely fit for sense but vnfit for motion. Some again conceiue and not without great reason that the softnesse or hardnes of a Nerue is diuersly occasioned, first from the substance whereout they yssue, and so the first nerues which are saide to arise out of the Braine are the softest, those harder that arise from the spinall mar∣row, and those hardest of all which arise from the marrow contained in the racke-bones of the Loines and the Holy-bone: Secondly in respect of their production, so those Nerues are soft which run but a little way, as if their iourney be not out of the scul, wher∣as those that are led further off as vnto the muscles are harder then they were at their Ori∣ginall.

In like manner those that run anfractuously, that is, with turnings and windings are very hard, as a branch of the third paire of the Braine. Againe, those are hard which p••sse tho∣rough a hard body; as that surcle of the fift coniugation which creepeth through the hole * 1.10 of the Temple-bone which the Ancients called Coecum or the blinde-hole is made harder by the contaction of the bone then his beginning was. Galen attributeth the cause of hard¦nesse and softnesse to the counsell of Nature, because, saith he, the instrument of Sense needed a soft nerue; A nerue as a Canale to leade along the Animall and sensatiue spi∣rit, and a soft nerue because it was to be affected and to suffer somwhat from the sensible obiect applying vnto it from without.

Nowe, because that which is soft is fitter for passion, that which is hard for action, therefore, saith he, it was necessary that the instruments of the senses should haue softe nerues communicated vnto them, and the parts which were to be mooued by voluntary motion should haue harder nerues. And this hee prooueth because vnto those Instru∣ments of sense which haue not only sensation but motion there is a double kind of nerue communicated, one for Sense, anotehr for Motion; as wee see in the eye vnto which the first coniugation is allowed for Sense and the second for Motion, so in the tongue which receiueth the third and fourth coniugations (so Anatomists do vsually distinguish them) for Tasting and the seuenth for Motion.

By the way hence it appeareth, that Nerues beside their vse haue also an animall ac∣tion * 1.11 because they are affected by the obiect, and therefore the softer nerues are fitter for Sense and the harder for Motion. Notwithstanding all this saith Bauhine yet wee con∣ceiue that the nerues of their owne nature are indifferently disposed both to sense and to motion, so that they may be called Sentientes or Motores, perceiuers or mouers from the instruments or parts vnto which they are conducted and in which they are disseminated, for if they be inserted into the instruments of motion, that is, into the muscles, then are they called Motorij or moouing nerues. If into the instruments of Sense then are they called Sensorij or perceyuing nerues; yea we see that one and the same nerue doth conuey * 1.12 motion and sense according to the diuersity of the instruments, for example; the seuenth Coniugation of the Braine conueyeth vnto the Membranes of the bowels which are in the middle and lower belly the Sense of Touching, and yet the same paire being on ey∣ther side reflected makes the recurrent nerue which distributeth surcles into euerie mus∣cle of the Larynx or Throttle to mooue the same. And if the same nerues shoulde meete with the instruments of Seeing, of Hearing and of Tasting, the same perceiuing & moo∣uing nerues would also become seeing, hearing and tasting nerues.

In like manner the nerues which are conueyed to the muscles to affoorde vnto them voluntary motion, do together with that power affoord vnto the membranes of the mus∣cles,

into which their fibres do determine, the sense of Touching, and so it commeth to passe that by the mediation of the nerues, the braine is to bee found in euery part of the body, because the animall faculty which is seated onely in the braine, doth notwithstan∣ding transfuse it selfe through the nerues.

Although out of that which hath been said we may easily collect the vse of the nerues, yet it shall not be amisse to remember that Galen in the ninth chapter of his fift booke de vsu partium, and out of him Vesalius in the first chapter of his fourth book makes a three∣fold * 1.13 vse of them.

The first to conuay sense vnto the instruments of sensation, to the eyes, to the tongue, to the eares, and beside these to the palmes of the hands and the in∣sides of the fingers yea to the vppermost mouth of the stomack also, for these after a sence are organs of sensation. For the best iudge by touching is the hand, and the mouth of the stomacke hath an exquisite sense of the want of aliment which wee commonly call Hunger.

The second vse is to affoord motion to the moueable parts, so the muscles which are the instruments of voluntary motion haue nerues conuayed vnto them, and because they were made to moue the whole members therefore their nerues are great and large, and because the same muscles stood in need of the faculty of discerning Tactile qualities for the security and preseruation of our liues, therefore also they had nerues by which nerues they haue this faculty of sensation.

The third vse is that for which all other parts haue nerues, to wit, that they might per∣ceiue those things which would be grecuous vnto them: (although this vse may wel be re∣ferred to the former) for so wise, so iust, so skilfull is Nature saith Hippocrates (wee say the great God of Nature) and so prouident for the behoofe of the creatures, that she hath di∣stributed nerues to all the parts although not in the same measure, but to some more libe∣rally to other with a strayter hand, and that according to the proportion of their mag∣nitude, of the dignity of their actions, of the intention or remission of their motions, of the assiduity or intermission of their vses. So making an exquisite estimate of the neede of the dignity and of the vse of euery part, to some she hath allowed greater nerues, to some lesser, but to euery one that is fittest for it.

For there is great difference betwixt the magnitude of nerues; the thickest are those which are distributed vnto the remorest places, and into the most parts, such are they that * 1.14 are sent vnto the ioynts, which because they needed greater aboundance of spirits haue a greater proportion of originals of sinewes granted them out of the stocke of the spinall marrow which is in the rack-bones of the necke and of the loines, that from their marrow they might receiue a competency of spirits as it were by many rootes, which yet being ga∣thered together do make one thicke nerue, but are againe though almost insensibly distri∣buted into lesser branches. Those nerues are Meane which are conuayed to the organs of the senses in the head: for being neare vnto the braine and very soft, they could not be very small. Those nerues are small which are distributed into the next parts, as into the muscles of the face. We will also say something concerning the originall of nerues.

The originall of the nerues is not from the heart though Aristotle so conceiued in the fift chapter of his third buoke de historia Animali: and in the fourth of his third de partibus * 1.15 Animalium, for in dissection we meete with no nerue produced therefrom, and those that are led vnto it from the sixt coniugation of the braine are so small, that Vesalius witnes∣seth that he could finde but one, and that with great difficulty.

Neyther haue they their originall as Erasistratus thought in his youth out of the Dura mater or thicke membrane of the braine as their substance already declared doth suffici∣ently witnes. But as Hippocrates, Erasistratus when he was wiser, Herophilus, Galen, and most Anatomists do agree from the braine, from which also the spinall marrow draweth his original. From the brain I say, which is manifested as wel by sense in the dissection ther∣of, where we see many riuers of nerues in the braine, to which those of the body are con∣tinuated: as also because their substances are marrowy alike and cloathed each of them with two membranes.

Moreouer the affects or diseases of the head doe manifestly proue that all Sense and motion doe flow from the Brayne. So in the Apoplexy which is caused by an obstructi∣on of the passages of the Brayne, the Animall Faculty is instantly intercepted, albeit the heart be altogether indempnified. So in the Epilepsie or Falling sicknes where the mar∣row

of the brayne from whence the nerues do yssue is affected, the whole body is drawn into Convulsion, which is nothing so when the heart is affected.

But we sayde before that a beginning is double, one of Generation another of Dis∣pensation. * 1.16 In respect of their Generation their beginning is Seede, of which as of their immediate matter they are framed. In respect of their Dispensation their beginning is in the brayne, together I meane with the After-brayne, which is the originall à quo from which. Those Pipes if so you list to call them, which receiue Sense and Motion are distri∣buted into the body, as the part standeth in need of the one, or the other, or both.

Againe, the Nerues are sayde to be of two sorts, some proceeding from the brayne, * 1.17 some from the spinall marrow, and of these againe some from the beginning of the Spi∣nall marrow, that is, being yet contayned in the scull, others in the Spinall marrow which is in the Rack-bones of the Chine. Againe, of these some belong to the marrow of the Necke, some of the Chest, some of the Loynes and some of the Os sacrum or Holy-bone, to which also we may adioyne the nerues of the Ioynts.

Bauhine in this place interposeth his owne opinion, which is, that all Nerues doe ys∣sue * 1.18 from the marrow of the brayne oblongated or lengthned out, some whilest it remay∣neth yet in the Scull and some after. But withall hee maketh mention of diuers opinions both of the Ancient and late Writers concerning the originall of the Nerues, which dis∣course of his we will here transcribe but contract it as briefly as we can. Hee reckoneth therefore eight opinions, for the ninth we thinke not worthy to be remembred.

The first is of Hippocrates in his booke de natura ossium in the very beginning, where * 1.19 he sayth that the original of the nerues is from the Nowle vnto the Spine, the Hippe, the Share, the Thighes, the Armes, the Legs and the Foote.

The second is Aristotles, who in many places deliuereth that they arise from the heart, because in it there are aboundance of nerues (for which hee mistooke the fibres) and be∣cause * 1.20 from thence motions doe arise, and vnder his Ensigne Alexander, Auicen and the whole schoole of the Peripateticks doe merrit or band themselues. This opinion of A∣ristotle, Auerhoes and Aponensis with some others doe maintayne indeede, but with a di∣stinction, affirming that they issue from the hart, mediante cerebro, by the mediation of the brayne, or that they arise from the heart and are multiplyed and propagated in the brain.

The third is that of Praxagoras, who thought that the Nerues were nothing else but * 1.21 extenuated Arteries.

The fourth of Erasistratus, who thought they yssued from the Dura meninx, but in his * 1.22 age he changed his mind as Galen witnesseth of him.

The fift is Galens, who determineth that the Nerues and the Spinal marrow doe pro∣ceede * 1.23 from the brayne.

The sixt is that of Vesalius, who saith that some Nerues issue out of the Scull, others * 1.24 out of the Racks of the Spine; those that proceede out of the Scull doe arise from the ba∣sis of the forepart of the braine or from the beginning of the Spinal Marrow before it en∣ter into the spondelles. The rest from the Spinall marrow remayning within the Racke∣bones.

The seauenth is Falopius his opinion in his obseruations, where hee sayeth, that some * 1.25 Nerues (as those that are soft) doe arise from the brayne or the marrow within the Scul, others from the Spinall marrow.

The eight is Varolius opinion, who sayth that all Nerues doe take their original from the Spinall marrow which proceedeth from the brayne and the After-brayne, and with * 1.26 him doe Platerus, Archangelus and Laurentius vpon the matter consent, as also doeth Bau∣hine as you haue heard before.

The Nerues therefore which yssue from the Marrow of the Brayne contayned yet within the Scull are commonly accounted 7 paires according to Galen, some make nine coniugations which are called Nerui cerebri The Nerues of the Brayne, which may be ex∣pressed in this disticke.

Optica prima, oculos mouit altera, tertia gustat Quartaque, quinta audit, vaga sexta, septima linguae est.

The Opticks first, Eye Mouers next, the third and fourth doe Tast: The fift doth Heare, the sixt doth gad, the Tongue claymes seuenth and last.

To which also we may adde the organs of Smelling.

Other Nerues do arise from the same marrow after it is falne through the great hole of the Nowle-bone and runneth thorough the holes bored in the racke-bones of the spine where it is properly called Spinalis medulla the Spinal Marrow. And these are thirty paires or Coniugations, that is to say; seuen of the Neck, of the Chest or backe twelue, fiue of * 1.27 the Loines and six of the Holy-bone from which the nerues of the ioynts do arise. For the hand receiueth sometimes fiue, some sixe propagations from the fift, sixt and seuenth paires of the necke, and from the first and second paires of the Chest: the foot receiueth foure Nerues from the three lower paires of the Loines and from the foure, sometimes the fiue vppermost of the Holy-bone which are called nerues of the spinall marrow.

These nerues do yssue on either side after the same manner, for no nerue is produ∣ced without his companion, and therefore the Grecians called them 〈 in non-Latin alphabet 〉〈 in non-Latin alphabet 〉, the Latines Neruorum paria, or Coniugia paires or Coniugations of nerues. All these Coniugati∣ons as they do arise alike, one from the right hand, the other from the left; so are they al∣so distributed after one and the same manner, except onely the sixt paire of the Braine, whose right nerue is not diuided as is the left, as we shall heare afterward.

And thus much shall haue bene sufficient to haue said in generall concerning the na∣ture, differences, vse and originall of the nerues. Now we descend vnto their particu∣lar Historie beginning with those of the Braine, because thence all nerues take their Ori∣ginall.

Notes

• * 1.1

  The names of Nerues and their kinds.
• * 1.2

  Compared to∣gether.
• * 1.3

  The descrip∣tion of anerue
• * 1.4

  Their substāce
• * 1.5

  Membranes.
• * 1.6

  Fernelius.
• * 1.7

  Which is their chiefe part.
• * 1.8

  How a Nerue is the Organ of Sense.
• * 1.9

  The reason of the softnes or hardress. of a nerue.
• * 1.10

  Galens opiniō.
• * 1.11

  Bauhines opi∣nion. His reasons.
• * 1.12

  An Instance.
• * 1.13

  The vses of the Nerues.
• * 1.14

  The magni∣tude of nerus.
• * 1.15

  Their origi∣nall.
• * 1.16

  An original double.
• * 1.17

  The differen∣ces of nerues.
• * 1.18

  Bauhines opi∣nion of the o∣riginall of nerues. 8. seueral opi∣nions quoted by him.
• * 1.19

  Hippocrates.
• * 1.20

  Aristotle.
• * 1.21

  Praxagoras.
• * 1.22

  Erasistratus.
• * 1.23

  Galen.
• * 1.24

  Vessalius.
• * 1.25

  Falopius.
• * 1.26

  Varolius.
• * 1.27

  30. pair of the spinall marow