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. XII. What a Membrane is, their Vses and Differences.

BY the common consent of Hippocrates, Galen and almost all Physi∣tians 〈 in non-Latin alphabet 〉〈 in non-Latin alphabet 〉, a Membrane and a Coate doe signifie one and the same thing. I knowe there is sometimes some nice diffe∣rence amongst the Grecians, but it is of no great consequence, & therefore I would haue you to vnderstand me to meane the same thing, when I speake of a Coate and of a Membrane. The defini∣tion of a Membrane is much more necessary, which Laurentius hath on this manner: It is a similar part, cold and dry, engendred of * 1.1 the slimy part of the seede, and therefore broad, thin and fast, the organe of the sense of Touch∣ing, keeping, knitting and separating the parts vnder it.

That it is similar it is manifest, because it is vniforme, and though it be wouen with fi∣bres yet are they not conspicuous. I speake here of true Membranes not of membranous bodies, such as are the wombe, the bladder, the stomacke, the guts and such like, which make a part of themselues, and wherein all the three sorts of fibres do appeare. That it is cold and dry, Galen teacheth in his Booke de temperamentis, but yet it is lesse cold and dry then a Tendon, a Ligament, a Gristle, or a Bone: but more cold and dry then Arteries, Veines and Sinewes. The matter of Membranes is the slimie part of the seede, which by the power of heate is stretched or distended; whence it is that a Membrane may easi∣ly be dilated or compressed without danger: onely the Membrane, saith Galen, may bee safely distended and contracted, and therefore all parts which were to bee distended and contracted are made membranous. A membrane is broad and extensible to inuest & pre∣serue the part: thight and fast for strength, and beside that it may not so easily receiue an influxion of humors, yet thin, least the waight of it should be offensiue. Notwithstanding though it be thin and appeare simple, yet euery Membrane is double; thorough which duplicature there runne Veines for nourishment, Arteries to conuey life and Nerues to conuey Sense, which vessels being slender and fine, it was fit it should be conueighed be∣twixt two coats.

The common office of a membrane is to be the organ of the Sense of Touching as the * 1.2 eye is the organ of Seeing, and therefore the sense of a membrane is most exquisite. A Nerue is indeede the conueyer of the spirits and carrieth downe the commandments of the Soule; but as in a muscle it is not the primary organ of motion, as in the eye it recei∣ueth not visible obiects, so it doth not receiue the first tactiue qualities, onely the Mem∣brane is it which we must esteeme the organ of Touching; and if you despoile the partes

of their membranes, you make them also insensible. Hence it is that the flesh of the lungs, of the liuer, of the spleene, and of the rest of the bowels is insensible. As therefore the sense of Touching is diffused throughout the whole body of the creature because it is euery where necessary: so likewise are there membranes sprinckled through the whole body almost internally and externally. On the outside the body is inuested with the skinne and the fleshy membrane. On the inside the peculiar membranes are almost infinite.

If it be obiected out of Galen in arte medicinali, that membranes haue onely inbred * 1.3 not influent faculties such as is sense. We answere with the Reconciler; that Galen then speaketh of membranous and broade ligaments which issue from the bones.

The three last particles of the definition do elegantly expresse the three principall v∣ses of membranes. They inuest the parts vnder them like a couering, whence they haue * 1.4 the name of coates. They conserue the fibres to make the flesh more firme and stable, they containe the substance of the parts and enclose it round about least it should dis∣solue and separate part from part.

Moreouer, they fasten one part to another, from whence proceedeth the admira∣ble * 1.5 simpathy or society of the parts. So by the periostia the bones are all continuated one to another; by their common membrane all the muscles are vnited: by the skin the whole body hath his connexion though it be diuers in respect of the structure of parts which are of diuers kindes.

Finally, by the helpe of membranes parts are separated from parts, as wee may per∣ceiue in our sections of muscles. There are other peculiar vses of membranes, to sustaine parts as appeareth in the Mediastinum: to hinder the refluence of humor as the values that are in the heart, in the great veynes and such like places, and to leade along and esta∣blish the vessels that are to be distributed into other parts, as into the mesentery, the kel, & the fleshy membrane.

The differences of membranes are manifold and are taken from their substance, mag∣nitude, * 1.6 site, figure, conformation or texture, and from the nature of the parts which they inuest or containe. If you regard the substance which is the Mansion-house and Ancient seate of the determinate and particular faculty, then wee say that membranes are either lawfull and true or illegitimate. Those are true membranes to which the definition be∣fore giuen wil agree, such are the membranes or Meninges of the braine, the Peritonaeum, the Pleura, the Periostium and such like; Illegitimate membranes may more truely be cal∣led membranous bodies. Of these there are three kindes, some arise from the bones, are broade and insensible, and fasten the ioynts together. Such are called Ligamentall mem∣branes or membranous ligaments. Others are made of the tendons of muscles dilated and so become more like a membrane then a tendon, such are the thin ends of the oblique and transuerse muscles of the Abdomen, also the tendon of the muscle that leadeth the leg backward, which they commonly call fasciam latam the broade swath. To the third kinde. I refer those membranous bod••es which make parts by themselues, which although they be inuested with coates, yet are altogether made of membranous bodies. Such are the bladders of vrine and gall the stomacke, the guts, and the wombe,

Againe, those membranes which I called legittimate, are eyther of a thin or slender substance like vnto broade cob-webbes, such as appeareth in that membrane or coate of the eie that compasseth the Cristaline humor called Arachnoides or the cob-webbe coate; likewise in the Pia mater of the braine, and in the coates of the Lungs and the Liuer; or they are thicke as the Dura mater and the membrane of the bladder; or they are fleshy as in the face, or altogether neruous.

From the magnitude some membranes are broade and some are long. The figure * 1.7 of membranes is manifolde according to the variety of the parts which they doe inuest. From the situation some are internall some are externall, some supernall some infernall. From the context or conformatiō some haue fibres of all three kindes, some of two kinds, some of one kind onely: others are without fibres and may be torne euery way as paper may.

And so much of membranes in generall, of their Nature, vses, and differences. Now we come vnto their history.

Notes

• * 1.1

  Definition of a Membrane.
• * 1.2

  The organe of Touching.
• * 1.3

  Obiection.
• * 1.4

  Galen ex∣pounded.
• * 1.5

  The vses of membranes.
• * 1.6

  The differen∣ces of mem∣branes. The first.
• * 1.7

  the second &c