The whole lower venter—for thence it is necessary to begin the dissection of the human body because that part putrefies very readily—from the outer skin to the peritoneum is called EPIGASTRION by the Greeks and mirach[1] by the Barbarians, of which the following are the parts.
The superficial skin which covers the whole body is completely insensitive. The skin lying and stretched under the very thin and superficial skin is sensitive.[2] The Greeks call it HYPODERMA. A kind of fat occupies the whole venter and is spread under the sensitive skin except for the middle.
A sinewy and thin membrane immediately follows this. A membrane taking origin from the muscles is subjoined firmly to this where a straight line appears in the middle.[3]
Two oblique descending muscles[4] lie under these toward the lowest venter. The oblique ascending muscles[5] are placed under these. Two rectus muscles have a close relationship. And lowest of all are the transverse muscles.[6] Therefore there are these eight for which there are nearly individual sinewy coverings by which they are distinguished from one another.
An aponeurosis, or rather a thick and firm membrane, is stretched under them which some falsely call the peritoneum. So much for the epigastrium and its parts.
Certainly the peritoneum is a sinewy part, soft to the touch, of ordinary firmness, occupying the whole venter, and resting under the aponeurosis or membrane which I mentioned. The Greeks gave that name to it. The Barbarians call it siphac.
The zirbus or omentum is extended under the peritoneum. The zirbus is a kind of fat derived from sinewy threads and the slender adipose substance of the nerves; it is less thick than the fat previously mentioned. It covers much of the intestines and the lowest part of the stomach and assists the coction of aliment.
The intestines take origin from the stomach; of them, that which is called rectum and longanon[7] is the lowest of all the intestines and contains the dry burden of the bowel, and its head extends outward between the nates so that it may dispose of its burden. The colon is continuous with it and in its ascent goes around the left kidney, and at the sides of the stomach it falls away to the right.[8] What the Greeks call TYPHLON and MONOPHTHALMON, the Romans the blind intestine and one-eyed,[9] is attached to the colon, of which it is the only passage; for the other end is closed so that it may assist coction more suitably in the manner of the stomach. Hence the name for the thing. And such is the number of the thicker intestines.
The caecum is continuous with the ileon,[10] an intestine twisted into numerous sinuses; from its shape the Greeks gave it the name PARA TOU EILEISTHAI, that is, from its involvement; and its disease is called iliacus. The jejunum follows it. Dissectors of bodies gave this name jejunum to the latter intestine because of the fact that it is always found empty and contains nothing. For the liver first snatches away whatever the jejunum might contain. Above all these intestines arises the duodenum which is continuous below with the jejunum and above with the pylorus. It is called DODEKA DAKTYLOM by the Greeks from the measure of twelve fingers. These three [intestines] by reason of their substance are called the slender intestines.
The stomach is located under the diaphragm, of which the upper mouth ends in the oesophagus, properly called stomachus; the lower opening through which aliment is sent into the intestines is called PYLOROS.
The spleen is an organ of rare substance and lies at the left side of the stomach; the liver being in the right hypochondrium. The latter is rounded and to some degree lunate, the former longish and somewhat quadrate. The gibbous part[11] of each of these extends toward the lower ribs, because there is a concavity in each of them which is very close to the stomach. The liver gives rise to the blood.[12] The spleen purges it of black bile. The spleen increases with loss to the rest of the body. The size of the liver is useful to the whole bodily structure, because it provides copious blood and natural spirit. The liver has lobes which the Greeks call LOBOUS, sometimes three, sometimes more,[13] and in its hollow extends the gall bladder by which the blood is freed of bile and issues forth pure. It is especially by exhalation and transpiration of this bladder that the duodenum and jejunum are sometimes stained;[14] sometimes they are irritated if there is a very large transpiration of particularly corrosive bile.
From the hollow of the liver[15] arises the portal vein which is formed from the concurrence of the many slender veins of the liver. On the other hand, it divides again into innumerable parts and gives off an immense multitude of veins which afterward are inserted here and there into almost all the intestines and to the little adipose membranes mixed together, so that they provide nutritional substance for the liver in the generation of blood. For chyle and food are sent down from the stomach directly to the intestines; the pylorus yields an exit as soon as the stomach has received as much as suffices for its uses and has accomplished its coction. Unless it be transmuted into the nature of blood [this food] contributes very little toward the nourishment of the rest of the body. Therefore these numerous venules serve to draw out from the intestines the best juice of the nutriment as yet not sufficiently concocted, and deliver it to the hollow of the liver where the blood is made. Doubtless those venules can be called meseraics, or by the Greek word mesenterics. The Latins call them milk veins.[16] For their protection, lest in their numerous ramifications some of them be torn apart or rent by a more vigorous motion of the body, the PANKREAS, that is, glandular flesh which is sometimes called KALLIKREAS by the Greeks, attaches to the duodenum so that the venules may individually be more firmly supported.
The blood passes from the hollow of the liver, in which it was formed a little earlier, to the gibbosity[17] of the liver; however, it is not the same kind as was made in the hollow but more pure and simple, since both biles have been strained from it and transmitted to their receptacles so that the blood may be more unsullied for nourishing the body wholesomely and for producing spirits. From the gibbosity the blood is extended throughout the whole body through the vena cava—called KOILE by the Greeks—and by the many branches of that vein. This vein surpasses all the rest of the veins of the body in size and arises from the gibbosity of the liver. Descending from this through the middle of the spine, one [branch] on each side seeks the kidneys, each branch extending a palm’s length.
These branches of the vena cava are the emulgent veins.[18] In the body of that one whom we dissected very recently the left branch had a higher place of origin.[19] Very often, however, the opposite occurs, so that the right emulgent vein is carried higher in the body. Nature employs these emulgent veins for carrying down the watery part and bile of the blood from the liver to the kidneys. A like number of little branches of arteries in the same site, from the great aorta artery going under the vena cava, run an equal length into the kidneys under the emulgent veins, unburdening the heart of bile and watery blood; these have the name of emulgent arteries.
A vein and artery descend from the left emulgents into the testis of the left side. They are the seminal passages swollen with blood and spirit; the seminal matter contained in them procreates females, because their humour is watery and requires coction. Seminal passages, likewise an artery and vein, are extended downward from the right [emulgents] into the right testis; but having arisen from the trunks of the vena cava and aorta artery, therefore the juice in them is less watery, and properly concocted is more suited for the generation of males. In these passages blood is concocted, and afterward transferred to the glandular flesh of the testes it acquires the form of semen.[20]
The kidneys are solid and hard organs, not sentient, and the attractive force in them is very powerful. They purge the blood of its watery part and bile, but they retain [some of] the blood so that they may be nourished by it and expel the rest of the humour. For the OURETERES are attached to them,[21] that is, the urinary passages, whitish, reed-like and tensile which it may be said extend to the bladder and are similar to its substance.
The diaphragm is a membranous substance, running between the vital and natural members. It is called DIAPHRAGMA by the Greeks. It strengthens the expulsive force in the intestines, it is assigned to the members selected for spirit, and it curbs the smoky vapours lest they blacken the vigorous spirits of the heart and brain. Above, there is affixed to it a sinewy covering[22] which clothes the thorax inwardly and binds the pectoral ribs to the interstitial spaces, which covering the Greeks in good part name PLEURA, but sometimes it is called HYPOZOMA[23] by them. By its inflammation pleurisy occurs, the name taken from the covering.
From the pleura near the spine arises a membrane separating the lungs and lower thorax into equal parts through the middle. It is commonly called the mediastinum, and is so well adapted to the lungs that a defect of one lung is not easily communicated to the other.[24] Certainly the lungs inhabit the middle palace of the chest, invigorate the spirits of the heart and brain, temper the heat and avert the danger of suffocation, and have lobes like the liver. They hold the heart constantly in a kind of embrace in the manner of very caressing nurses and sing a harmony of qualities by which they soothe the individual parts of the body and make them vigorous. From that part of the mediastinum which holds the middle of the lungs, a thick and hard membrane appears which completely covers the heart,[25] called in Greek PERIKARDION. This protects the heart lest it be afflicted by accidental things; and lest it lack the moistening fomentation by which its heat is moderated. It unites the forces of the heart and prevents the exhaled spirits from being dispersed by vehement motion. Here the heart establishes itself, prince of members[26] and an organ sharpened into [the shape of] a top; hollow within; continuously palpitating by its three ventricles,[27] with an auricle on each side in which life remains the longest.[28] The seat of the spirit and a small amount of blood is in the left ventricle of the heart, from which the pulmonary vein advances and enters the lungs to receive better-prepared air from them;[29] this it introduces into the ventricles of the heart lest they become unduly heated. The right ventricle contains more and very hot blood. The vena cava rises into this[30] through the middle of the spine and pours in the tinder of the vital spirit from the liver. From this the pulmonary artery belches much blood into the lungs. In the ventricle between the right and left there is tempered blood of slight quantity. From this ventricle the large artery called the aorta arises, the vehicle of the vital spirits; it is constantly agitated up and down by the contrary motions of dilatation and constriction, and finally it is divided into myriads of branches so that it revivifies the living parts in the whole body by a gentle flatus. This is the end of the account of the vital members.
The membrane covering the bony roundness of the head outwardly is called PERIKRANION by the Greeks, and it is hard, thick and firm, and conforms in substance to the exterior covering of the brain which is commonly called the dura mater. The covering of the dura mater hangs affixed to the pericranium, so it seemed to nature, lest in contact it have an effect on the brain; under this covering a thin and soft membrane, which is called the pia mater, sprinkled with numerous veins, envelops and nourishes the brain. It is continuous to the dura mater and the substance of the brain, and it penetrates the ventricles of the brain. Hence the brain displays itself very clearly to the eyes, both its ventricles and the cerebellum placed at the rear of the head from which the medulla descends into the vertebrae of the spine. Here the reticular plexus (commonly called the rete mirabile), woven together from numerous slender threads of veins and arteries at the summit of the cerebellum, displays its phantasia; in it the vital spirit carried upward from the heart through the arteries, having been fully concocted and rarefied, becomes animal spirit, the cause of sensation and motion in the whole body. For the brain is the source of the nerves, but the nerves are the vessels which distribute animal spirit;[31] from the medulla of the spine (it is called nucha by the Barbarians) they are distributed to all parts of the body. Furthermore, there extend from the brain seven pairs of nerves.[32] Two nerves look forward to the nares,[33] the olfactory organs. Two are carried to the eyes,[34] intersecting in their course, from whence comes the faculty of vision. Another two [carry] motion to the eyes,[35] another two give motion and taste to the tongue.[36] From two the stomach acquires sensation[37] so that appetite may not be lacking to it, and from as many slender nerves the palate distinguishes flavours.[38] Finally, from a single origin one nerve is extended on each side, provided for the right and for the left ear lest they be struck by deafness.[39] These things which have been said by me briefly regarding the animal members, within the proposed limits, end this introduction to anatomy. Other matters which pertain to this subject I shall discuss in another work where we shall adapt the discourse to all aspects of anatomy.
Printed by Rob. Redman in London
M.D.XXXII
With Privilege
