Part 9

3d. Above and behind, the cerebral texture is continued with that of the corresponding parts of the head, by the numerous but small openings in the sutures; it accompanies the vessels that go from the dura-mater to the pericranium, and it becomes probably sometimes the means of communication, that is so frequently observed between these two membranes, when one is inflamed; hence the sudden affection that frequently takes place of the dura mater, tunica arachnoides, &c. from a stroke of the sun upon the integuments of the cranium, &c.

The cellular texture, though more abundant on the outside of the cranium, is not found in great quantity there, no doubt because the muscles are so few and thin. Its communications with the face are evident, especially upon the forehead; as a consequence of erisypelas of the cranium, nothing is more common than to see the eye-lids receive the pus that is formed, and which often accumulates in these moveable veils, so as to occasion considerable deposits. It is by these communications also that serum is deposited there, and blood extravasated. Behind and upon the sides, the communications of the cellular texture of the cranium are also very evident.

_Cellular texture of the face._

It is very abundant in every part. The orbits are filled with it; the excavation of the cheeks, that is bounded by the buccinator and masseter muscles, the zygomatic and malar bones, contain much of it: all the neighbouring parts of the tongue are furnished with it. The nasal cavities only and their sinuses, which a mucous surface covers, that is almost immediately attached to the bone, have but a small quantity of it.

The facial cellular texture contributes to the beauty and harmony of the countenance, the features of which, examined closely, show that the muscles draw in an unpleasant manner across the skin, when there is no fat, and consequently that there is too great a depression. In an opposite state, there is a kind of bloating that is disagreeable; a middle state is the most favourable to the beauty of the face. This texture is almost wholly disconnected with expression, which is effected by the muscles. Thus the different passions are delineated with nearly the same features upon a fat and a lean face. Only these features are less marked in the first than the second, because in the last more wrinkles are formed than in the other, by the contraction of the same muscles.

The cellular texture is in greater or less quantity in the face in different people. Every one knows that some are always thin in this part, who are fat in the rest of the body. From the dissection of the bodies of such persons, I have found that it arises from the small quantity of cellular texture it contains in proportion to the other parts. In other individuals, there is an opposite state, a fulness of the face with a lean body, a striking contrast, and which arises without doubt from a cause opposite to the first.

It is to the greater proportion of cellular texture, much more than to the development of the muscles, that must be attributed the evident thickness of certain parts of the face, in different species of the human race, that, for example, of the lips and the alæ of the nose in negroes, &c. From the same cause arises the variety in thickness in the great and small labia pudendi.

The principal communications of the facial cellular texture are made with the neck by the sub-cutaneous portion of this texture, by that which accompanies the vessels, and particularly in the triangular space at the superior part of which is situated the parotid gland. Thus, from deposits made upon the lateral parts of the face, effusions of pus take place that often extend to the neck. In emphysema, the air of which comes from the chest, after the neck is swelled, the air passes to the face principally by the sides. There are still great communications of cellular texture between the neck and the face, by the spaces between the muscles that are attached to the base of the tongue.

II. _Cellular system of the trunk._

It varies in its proportions, as we examine the regions of the spine, the neck, the chest, the abdomen, and pelvis.

_Vertebral cellular texture._

I so call the cellular texture which is found in the neighbourhood of the spine, and in the vertebral canal.

In the cavity of this canal, there is but very little of it. Between the tunica arachnoides and the medulla oblongata, between the nervous elongations that go from the last, and the sheaths of the arachnoides that accompany them, we see some filaments that follow the course of the vessels, and contribute to the formation of the pia mater. There is none of this texture between the arachnoides and dura mater. Below this, between it and the vertebral canal, in the places where it does not adhere, there is more of it, especially below, where it is very loose, and always covered with a fluid that is often reddish.

On the outside of the spine, we see, behind, many muscles and but little cellular texture in proportion; thus, depositions in this part are much more rare and much less liable to spread than elsewhere, a circumstance which arises also from this, that the muscles being very compact in the vertebral canals, keep in a state of depression the cellular texture that separates them.

This texture is on the contrary very abundant along the whole course of the anterior part of the spine, in the neck, where it accompanies the carotids, in the thorax and abdomen, where it follows the course of the aorta, the great trunks which go from it, the vena cava, azygos, &c. There is no part of the animal economy, more frequently exposed to different collections of pus, than this. Nothing is more common than to see depositions that are formed at the anterior part of the thorax and abdomen, projecting at the groin by a channel which we discover by the examination of bodies. It is principally by these cellular communications, and by those which are beneath the integuments, that the superior parts correspond with the inferior, and vice versa.

_Cervical cellular texture._

The neck, which is very muscular, has much cellular texture, besides that which belongs to the vertebral column. It is especially in the lateral parts, where the lymphatic glands are situated, that this texture is remarkable. In the space between the sterno-cleido-mastoideus and trapezius muscles, where the brachial nerves arise, and where the vessels pass that go from the thorax, there is a great quantity of it. It communicates with that of the thorax, by the large opening that is found at the superior part of this cavity; hence it happens, that when the cells of the lungs are ruptured, the escaped air occupies first the chest and then the neck, and hence also the facility with which we produce the same phenomenon by forcing air beneath the pleura of a dead body, &c.

The cellular texture of the neck communicates also with that of the superior extremities above and below the clavicle. Hence why the neck and consequently the chest, are filled with air, water, and other fluids that are forced into the sub-cutaneous and intermuscular texture of these extremities.

_Pectoral cellular texture._

In the pectoral cavity, it is upon the median line that the cellular texture is especially found; it is abundant in the space formed by the duplicature of the mediastinum; the neighbourhood of the pericardium is supplied with it, particularly around the great vessels, which it accompanies a short distance; the rest of the thorax, occupied by the lungs, contains much less of it.

The pectoral texture communicates with the abdominal, 1st. by the different openings of the diaphragm, by that of the aorta, and particularly of the œsophagus; that of the vena cava being too closely united to that vessel, to permit these communications easily; 2d. by the opening of the diaphragmatic fibres, especially by the triangular space, through which those pass that are attached to the ensiform cartilage; hence the passage of the deposits from the thorax to the abdomen. Desault mentions a purulent collection, first formed in the neck, and which by the anterior mediastinum, became prominent just above the abdomen. Hence the facility with which the pleura particularly on the right side receives the influence of diseases of the peritoneum, when this is diseased on the convex surface of the liver which always keeps its place, whilst by the motions of the stomach and the spleen, that which covers those two viscera, which are constantly changing their situation, has a much less decided influence upon the left pleura.

The cellular communications of the chest take place also from the interior to the exterior, by the interstices between the intercostal muscles, but they are not very evident, as these interstices are very small; thus the diseases of the breast have rarely any influence out of this cavity; this happens however when in dropsies and chronic inflammations of the pleura, the pectoral integuments have an adhesion to the diseased side.

The exterior cellular texture of the chest, is very abundant above; it there surrounds the breasts and contributes in part to those rounded forms that delight us in women, and those prominent ones which we admire in a well formed man. We see it in great quantities under the pectoral muscles; below it diminishes in a very evident manner.

_Abdominal cellular texture._

The abdomen contains, in proportion a little more cellular texture than the thorax. In the interior of this cavity, this texture is found collected in the places where the great arteries and veins enter the gastric organs, as in the fissure of the liver, the mesentery, &c. It is not abundant between the peritoneum and the anterior and lateral parietes of the abdomen, but it is so on the posterior part of this membrane, particularly about the kidnies. This interior texture communicates at first with that of the pelvis, all around the peritoneum, then with that of the lower extremities, by different openings, by the inguinal ring and especially by the crural arch. The first of these openings establishes also a cellular correspondence between the abdomen and genital organs, particularly in man. We can easily prove these communications by injecting a fluid into the abdominal cellular texture of a dead body. This fluid goes spontaneously to the inferior extremities, whilst it requires a long continued force to drive it to the superior. All practitioners know, that there is hardly any case of ascites, in which the lower extremities are not swelled, while the superior are unaltered. It is then with the abdominal cellular texture, that that of the inferior extremities has a particular relation, as it is with the pectoral that that of the superior corresponds, as has been observed by Bordeu and Portal. It is to be remarked however, that the first are affected much more easily in the diseases of the abdomen, than the second are in those of the chest.

_Cellular texture of the pelvis._

There are but few parts in which the cellular texture is more abundant than in the pelvis. Around the bladder, rectum and womb there is a great quantity of it, it is found no where more abundantly. This appears to me to be the cause of it; that, as these three organs are subject to great dilatation, and as the osseous parietes of the pelvis cannot yield to these dilatations, like the abdominal parietes, it is necessary that something should so act, that in whatever state the preceding organs may be, the cavity of the pelvis should be always filled. If the motions of the brain alternately increased and diminished the size of this organ, the bony cavity of the cranium would have been lined without doubt with cellular texture.

Besides we know the effect of this large quantity of cellular texture in the pelvis, in deposits which take place in the neighbourhood of the anus, in infiltrations of urine which accompany ruptures of the urethra and bladder. The facility with which pus and urine spread themselves in this part and the mischief they occasion, are well known.

This texture communicates with that of the inferior extremities by the ischiatic notch, by the arch of the pubis, &c. Different authors mention, that effusions of pus and urinous infiltrations extend downwards by these communications. We can fill the pelvis with air, by blowing this fluid into the inferior extremities, especially in their intermuscular texture.

The exterior of the cavity of the pelvis has also much cellular texture, less however behind than upon the sides, but in front around the genital organs of man as well as woman, there are large masses, particularly upon the great labia and the dartos.

III. _Of the cellular system of the extremities._

In the superior and inferior extremities, the quantity of cellular texture decreases from the superior to the inferior part. Around the two superior articulations, it is very abundant. The hollow of the axilla, in which the head of the humerus is situated, and which is spacious, is almost entirely filled with it. The groin has also considerable, though less than the axilla. The arm and the thigh have between their muscles large interstices that are cellular. At the elbow there is a smaller proportion than at the ham, whose deep cavity has a considerable quantity; an arrangement that is consequently the reverse of that of the axilla compared with that of the groin.

In the fore arm and leg, the muscles approach each other in a sensible manner; their cellular layers are much more compact, the whole cellular system is less abundant.

Towards the inferior part of these two portions of the limbs, where almost every thing on the hand and foot are tendinous and fibrous, the cellular texture diminishes still more, and becomes in proportion to the motions, hardly sensible. However, the foot, especially on the sole, contains much more than the palm of the hand, where we see but little.

This successive decrease of the cellular texture of the limbs is adapted to the uses of their different parts. In fact the extent of motion that exists above, requires in the muscles a laxity which they borrow from the quantity of cellular texture that surrounds them. Below, the multiplicity and at the same time the limited extent of the motions of the hand and the foot, of the hand especially which is destined to adapt itself to the form of external bodies, require in the organs of these two parts a close juxta-position, for which they are indebted to the small quantity of cellular texture that exists there.

ARTICLE THIRD.

OF THE FORMS OF THE CELLULAR SYSTEM, AND THE FLUIDS IT CONTAINS.

I. _Of the cells._

The general conformation of the cellular texture is not the same every where. The interstices or cells between the different layers, are more or less wide; their size is remarkable upon the eyelids and the scrotum, and in general where there is no fat, or where it is in small quantity. Moreover the capacity of the cells is extremely variable; nothing definite can be determined upon this point, as they are capable of contraction and expansion. When fat and serum fill them, they are double, triple or even quadruple what they are when they are empty. It is the variation in the size of the cells of the system of which we speak, which constitutes all the difference of the general size of the body in corpulency or emaciation; in each state the size of every nervous, tendinous fibre, &c. remains nearly the same, and the cellular system only varies. There is the same variety in leucophlegmasia compared with the ordinary state of the body.

The figure of the cells is so variable, that we cannot describe them in a general manner. Round, quadrangular, hexagonal, oval, are found mixed together. The best way to see these, is to freeze an infiltrated limb; numerous little icicles are then formed, and show by their form, that of the cells which they filled. Artificial emphysema is also a good way; I have often determined by it in our slaughter houses where they blow meats, the forms of the cells. The injection of melted gelatine may also be employed; but the results are less certain, because in going from one cell to another, it breaks the texture; and moreover after it is hardened, it is difficult to separate each portion contained in each cell.

All the cells communicate; so that the cellular texture is really permeable throughout the whole extent of the body, from the feet to the head. This permeability is proved, 1st. by emphysema spontaneously produced; 2d. by that which is artificially produced in a living animal, by blowing air under any portion of the cutaneous organ, an operation which affects neither the life or health of the animal, though oftentimes the whole of the body is bloated. We know that some beggars make use of these means without danger, for the purpose of exciting compassion. 3d. If one or two punctures are made in a dropsical limb, it is sometimes wholly emptied in this way. 4th. Oftentimes this happens from ruptures taking place spontaneously in limbs of this kind. 5th. Pressure made upon them, makes the fluid ascend or descend, according to the part upon which it is made. 6th. A rupture of the bladder or the urethra produces an urinous infiltration, which sometimes extends even to the sides of the chest. 7th. The injection of any fluid into the cellular texture of a dead body, produces an artificial leucophlegmasia.

The permeability of the cellular texture has been much exaggerated, or rather it has been presented under a point of view different from that in which it is shown by nature. It is thus that many physicians, thinking that it could be pervaded indifferently by all the fluids of the animal economy, have believed that these fluids formed there, currents in different directions more or less irregular. Thus the sweat has been considered as the transmission by the skin of the albuminous fluid of the cellular texture, which, according to some moderns, is drawn out with the caloric that is constantly disengaged. They have thought, also, that the permeability of this texture would explain the rapid passage of drinks to the bladder. They have explained by it too, the promptness with which sweat is produced by warm liquors, &c.

All these theories, that examination never proves, are repugnant to the known laws of our economy, laws which show us the fluids constantly circulating in the vessels, in consequence of the vital forces, of organic sensibility and contractility which they possess, and not as being extravasated to move irregularly in the cellular texture. Moreover, I have never found any portion of drink in the cellular texture of animals immediately after they have taken it. I have tried many of these experiments upon dogs, after having deprived them for some time of drink, that they might drink the more. The cellular texture in the neighbourhood of the stomach and intestines, that especially which, placed behind the mesentery, communicates with the pelvis where the bladder is situated, having been attentively examined, did not appear to me to contain any fluid; it was analogous to that of the other parts of the body. Besides, as we shall see hereafter, these phenomena can be explained in a very natural manner.

The cellular texture is permeable, then, only to fat and lymph; and yet it appears that but little use is made in an ordinary state of this permeability by these two fluids, which remain in their cells, until absorption takes them up. We do not see them pass from one to another; they are stagnant, if we may so say. It is only in serous infiltrations, in effusions of pus, in one word, in a morbid state, that the cellular permeability becomes apparent. We can only consider, then, the cellular texture as the reservoir, in which are formed the serum and the fat. After death the cellular texture is every where penetrated by fluids, which pass not only across the communicating openings of its cells, but also through the pores which it has, like all the solids; hence the infiltration of the integuments of the back, in dead bodies that have been laid upon it for a length of time; hence also the passage of the bile through the texture, which separates the gall bladder from the duodenum, and by which means this intestine is discoloured, &c. &c. But these phenomena have nothing in common with those that take place in the living body.

II. _Of the serum of the cellular membrane._

The first of the two cellular fluids appears to be the same as that which is elsewhere furnished by the exhalants and taken up by the absorbents. The first deposit it in the organs, the second carry it from them. Thus when we expose to the air condensed by cold any part of the cellular texture of an animal recently killed and still preserving its heat, we see a vapour arise which results from the solution of the serum in this air, a vapour perfectly analogous to a cloud that transpiration and respiration produce in winter, or even to that which arises from any aqueous fluid, exposed hot, with a large surface to the action of fresh air. When the atmosphere is warm the solution takes place in the same way, but as the vapour is not condensed, there is no apparent cloud.

The cellular serum varies in quantity in the different regions. Where there is no fat, as in the scrotum, the eye-lids, the prepuce, &c. it appears to be a little more abundant than elsewhere. We see also that these parts are much more disposed to different infiltrations. In this respect, the scrotum holds the first rank; then come the eye-lids, afterwards the prepuce, &c. Observe upon this subject, that the cellular texture exterior to the mucous surfaces, the arteries, the veins, and excretories, a texture which by the absence of fat resembles the ordinary, differs from it, however, in this, that serum is never effused in it.

We cannot judge of the quantity of cellular serum by observations made upon the dead body, in which the laxity of the parts permits a transudation of the fluids from all the vessels that pass through the cellular texture, and which then enter the cells. To estimate accurately the cellular moisture, I made an animal first emphysematous below the skin; I made a large incision into this; little blood only escaped, because the swelling separated the vessels from the course of the knife. By these means, the cellular texture being laid open, I have often been convinced that there was much less serum in this texture than we commonly suppose. I have not observed, that during digestion, after sleep, and whilst much sweat is exhaled by the cutaneous organ, three circumstances under which I have repeated these experiments, that the cellular serum is increased or diminished in a sensible manner. This fact coincides with what I have stated in my Treatise on the Membranes, upon the fluid that lubricates the serous surfaces, and the proportion of which is almost always nearly equal.

We know that in leucophlegmasia, the quantity of cellular serum is much increased; that it disappears in inflammation, &c.