The Politics of Aristotle

by Aristotle

  In all viviparous animals furnished with feet the following properties are observed in the testicles themselves. From the aorta there extend vein-like ducts to [15] the head of each of the testicles, and another two from the kidneys; these two are supplied with blood, while the two from the aorta are devoid of it. From the head of the testicle alongside of the testicle itself is a duct, thicker and more sinewy that the others, that bends back again at the end of the testicle to its head; and from the head [20] of each of the two testicles the two ducts extend until they coalesce in front at the penis. The duct that bends back again and that which is in contact with the testicle are enveloped in one and the same membrane, so that, until you draw aside the membrane, they seem to be a single duct. Further, the duct in contact with the [25] testicle has its moist content qualified by blood, but to a comparatively lesser extent than in the case of the ducts higher up which are connected with the aorta;2 in the ducts that bend back towards the tube of the penis, the liquid is white-coloured. There also runs a duct from the bladder, opening into the upper part of the tube, around which lies, sheath-wise, what is called the penis.

  [30] All this may be studied by the light of the accompanying diagram; wherein the letter A marks the starting-point of the ducts that extend from the aorta; the letters KK mark the heads of the testicles and the ducts descending to them; the ducts extending from these along the testicles are marked ΩΩ the ducts turning back, in which is the white fluid, are marked BB; the penis Δ; the bladder E; and the testicles ΨΨ.

  If the testicles themselves are cut off or removed, the ducts draw upwards by [510b1] contraction. Moreover, when male animals are young, people sometimes destroy the testicles by rubbing; sometimes they castrate them at a later period. And I may here add, that a bull has been known to serve a cow immediately after castration, and actually to impregnate her.

  So much then for the properties of testicles in animals. [5]

  In animals furnished with a womb, the womb is not in all cases the same in form or endowed with the same properties, but both in the vivipara and the ovipara great diversities present themselves. In all creatures that have the womb close to the genitals, the womb is forked and one fork lies to the right-hand side and the other to [10] the left; its commencement, however, is single, and so is the orifice, resembling in the case of the most numerous and largest animals a tube composed of much flesh and gristle. Of these parts one is termed the hystera or delphys, whence is derived ἀδελφός, and the other part, the tube or orifice, is termed metra. In all biped or [15] quadruped vivipara the womb is in all cases below the midriff, as in man, the dog, the pig, the horse, and the ox; the same is the case also in all horned animals. At the extremity of the so-called horns, the wombs of most animals have a convolution.

  In the case of those ovipara that lay eggs externally, the wombs are not in all [20] cases similarly situated. Thus the wombs of birds are close to the midriff, and the wombs of fishes down below, just like the wombs of biped and quadruped vivipara, only that, in the case of the fish, the wombs are delicately formed, membranous, and elongated; so much so that in extremely small fish, each of the two bifurcated parts [25] looks like a single egg, and those fishes whose egg is described as crumbling would appear to have inside them a pair of eggs, whereas in reality each of the two sides consists not of one but of many eggs, and this accounts for their breaking up into so many particles.

  The womb of birds has the lower and tubular portion fleshy and firm, and the part close to the midriff membranous and exceedingly fine: so fine that the eggs might seem to be outside the womb altogether. In the larger birds the membrane is [30] more distinctly visible, and, if inflated through the tube, lifts and swells out; in the smaller birds all these parts are more indistinct.

  The properties of the womb are similar in oviparous quadrupeds, as the tortoise, the lizard, the frog and the like; for the tube below is single and fleshy, and [511a1] the cleft portion with the eggs is at the top close to the midriff. With animals devoid of feet that are internally oviparous and viviparous externally, as is the case with the dogfish and the other so-called Selachians (and by this title we designate such [5] creatures destitute of feet and furnished with gills as are viviparous), with these animals the womb is bifurcate, and beginning down below3 it extends as far as the midriff, as in the case of birds. There is4 also a narrow part between the two forks running up as far as the midriff,5 and the eggs are engendered here and6 above at the [10] origin of the midriff; afterwards they pass into the wider space and turn from eggs into young animals. However, the differences in respect to the wombs of these fishes as compared with one another and with fishes in general, would be more accurately studied in their various forms in the Anatomies.

  The members of the serpent genus also present divergencies either when [15] compared with the above-mentioned creatures or with one another. Serpents as a rule are oviparous, the viper being the only viviparous member of the genus though it is first internally oviparous; and owing to this peculiarity the properties of the womb in the viper are similar to those of the womb in the selachians. The womb of the serpent is long, in keeping with the body, and starting below from a single duct [20] extends continuously on both sides of the spine, so as to give the impression of thus being a separate duct on each side of the spine, until it reaches the midriff, where the eggs are engendered in a row; and these eggs are laid not one by one, but all strung together. [And all animals that are viviparous both internally and externally have the womb situated above the stomach, and all the ovipara underneath, near to [25] the loin. Animals that are viviparous externally and internally oviparous present an intermediate arrangement; for the underneath portion of the womb, in which the eggs are, is placed near to the loin, but the part about the orifice is above the gut.]7

  Further, there is the following diversity observable in wombs as compared with one another: namely that the females of horned animals which do not have teeth in [30] both jaws are furnished with cotyledons in the womb when they are pregnant, and such is the case, among animals with teeth in both jaws, with the hare, the mouse, and the bat; whereas all other animals that have teeth in both jaws, and are viviparous and furnished with feet, have the womb quite smooth, and in their case the attachment of the embryo is to the womb itself and not to any cotyledon.

  The parts, then, in animals that are not uniform, both parts external and parts internal, have the properties above assigned to them.

  [511b1] 2 · In sanguineous animals the uniform part most universally found is the blood, and its habitat the vein; next in degree of universality, their analogues, lymph [5] and fibre, and, that which chiefly constitutes the body of animals, flesh and whatsoever in the several parts is analogous to flesh; then bone, and parts that are analogous to bone, as fish-bone and gristle; and then, again, skin, membrane, sinew, hair, nails, and whatever corresponds to these; and, furthermore, fat, suet, and the [10] excretions—dung, phlegm, yellow bile, and black bile.

  Now, as the nature of blood and the nature of the veins have all the appearance of being fundamental, we must discuss their properties first of all, and all the more as some previous writers have treated them very unsatisfactorily. And the cause of the ignorance is the extreme difficulty experienced in the way of observation. For in [15] the dead bodies of animals the nature of the chief veins is undiscoverable, owing to the fact that they in particular collapse at once when the blood leaves them; for the blood pours out of them in a stream, like liquid out of a vessel, since there is no blood separately situated by itself, except a little in the heart, but it is all lodged in the veins. In living animals it is impossible to inspect these parts, for of their very nature [20] they are internal. For this reason those who have carried on their investigations on dead and dissected bodies have failed to discover the chief sources of the veins, while those who have narrowly inspected bodies of living men reduced to extreme attenuation have arrived at conclusions regarding the origin of the veins from the manifestations t
hen visible externally. Syennesis, the physician of Cyprus, writes as follows:— [25]

  ‘The big veins run thus:—from the eye, across the eyebrow, along the back, past the lung, in under the breasts; one from right to left, and the other from left to right; that from the left, through the liver to the kidney and the testicle, that from the right, to the spleen and kidney and testicle, and thence to the penis’.

  Diogenes of Apollonia writes thus:— [30]

  ‘The veins in man are as follows:—There are two veins pre-eminent in magnitude. These extend through the belly along the backbone, one to right, one to left; either one to the leg on its own side, and upwards to the head, past the collar bones, through the throat. From these, veins extend all over the body, from that on [512a1] the right hand to the right side and from that on the left hand to the left side; the most important ones, two in number, to the heart in the region of the backbone; others a little higher up through the chest in underneath the armpit, each to the hand on its own side, one being termed the splenetic, and the other the hepatitic. [5] Each of the pair splits at its extremity; the one branches in the direction of the thumb and the other in the direction of the palm; and from these run off a number of minute veins branching off to the fingers and to all parts of the hand. Other veins, more minute, extend from the main veins; from that on the right towards the liver, [10] from that on the left towards the spleen and the kidneys. The veins that run to the legs split at the juncture of the legs with the trunk and extend right down the thigh. The largest of these goes down the thigh at the back of it, and can be discerned as a big one; the second one runs inside the thigh, not quite as big as the one just [15] mentioned. After this they pass on along the knee to the shin and the foot, like those which lead towards the hands8 and arrive at the sole of the foot, and from thence continue to the toes. Moreover, many delicate veins separate off from the great veins towards the stomach and the ribs. [20]

  ‘The veins that run through the throat to the head can be discerned in the neck as large ones; and from each one of the two, where it terminates, there branch off a number of veins to the head those from the right side towards the left, and those from the left side towards the right; and the two veins terminate near to the ears. There is another vein in the neck running along the big vein on either side, slightly [25] less in size than it, and with these the greater part of the veins in the head are connected. They run through the throat inside; and from either one of the two there extend veins in underneath the shoulder blade and towards the hands; and these appear alongside the splenetic and hepatitic veins as another pair of veins smaller in [30] size. When there is a pain near the surface of the body, the physician lances these two latter veins; but when the pain is in the region of the stomach he lances the splenetic and hepatitic veins. And from these, other veins depart to run below the breasts.

  [512b1] ‘There is also another pair running on each side through the spinal marrow to the testicles, thin and delicate. There is, further, a pair running beneath the skin through the flesh to the kidneys, and these with men terminate at the testicle, and with women at the womb. These are termed the spermatic veins.9 The veins that [5] leave the stomach are comparatively broad just as they leave; but they become thinner, until they change over from right to left and from left to right.

  ‘Blood is thickest when it is imbibed by the fleshy parts; when it is transmitted [10] to the regions above-mentioned, it becomes thin, warm, and frothy’.

  3 · Such are the accounts given by Syennesis and Diogenes. Polybus writes to the following effect:—

  ‘There are four pairs of veins. The first extends from the back of the head, [15] through the neck on the outside, past the backbone on either side, until it reaches the loins and passes on to the legs, after which it goes on through the shins to the outer side of the ankles and on to the feet. And it is on this account that surgeons, for pains in the back and loin, bleed in the ham and in the outer side of the ankle. [20] Another pair of veins runs from the head, past the ears, through the neck: they are termed the jugular veins. This pair goes on inside along the backbone, past the muscles of the loins, on to the testicles, and onwards to the thighs, and through the inside of the hams and through the shins down to the inside of the ankles and to the [25] feet; and for this reason, surgeons, for pains in the muscles of the loins and in the testicles, bleed on the hams and the inner side of the ankles. The third pair extends from the temples, through the neck, in underneath the shoulder-blades, into the lung; the one running from right to left in underneath the breast and on to the spleen [30] and the kidney; the other from left to right from the lung in underneath the breast and into the liver and the kidney; and both terminate in the rectum. The fourth pair [513a1] extend from the front part of the head and the eyes in underneath the neck and the collar-bones; from thence they stretch on through the upper part of the upper arms to the elbows and then through the fore-arms on to the wrists and the jointings of [5] the fingers, and also through the lower part of the upper-arms to the armpits, and so on, keeping above the ribs, until one of the pair reaches the spleen and the other reaches the liver; and after this they both pass over the stomach and terminate at the penis’.

  That, pretty well, is what others have said. There are also some writers on [10] nature who have not dealt in such precise terms with the veins, but who all alike agree in assigning the head and the brain as the starting-point of the veins. And in this opinion they are mistaken.

  The investigation of such a subject, as has been remarked, is one fraught with difficulties; but, if any one is keenly interested in the matter, he will get an adequate grasp of it only if he studies strangled animals which have been previously emaciated. [15]

  The nature of the veins is as follows. There are two veins in the thorax by the backbone, and lying to its inner side; and of these two the larger one is situated to the front, and the lesser one is to the rear of it; and the larger is situated rather to the right-hand side of the body, and the lesser one to the left; and by some this vein is termed the aorta, from the fact that even in dead bodies they have observed the [20] sinewy part of it. These have their origins in the heart, for they traverse the other viscera, in whatever direction they happen to run, without in any way losing their distinctive characteristic as veins, whereas the heart is as it were a part of them (and that too more in respect to the frontward and larger one of the two), owing to the [25] fact that these two veins are above and below, with the heart lying midway.

  The heart in all animals has cavities inside it. In the case of the very small animals the largest of the chambers is scarcely discernible; the second larger is scarcely discernible in animals of medium size; but in the largest animals all three [30] chambers are distinctly seen. In the heart then (with its pointed end directed frontwards, as has been observed) the largest of the three chambers is on the right-hand side and highest up; the least one is on the left-hand side; and the medium-sized one lies between the other two; and the largest one of the three chambers is a great deal larger than either of the two others. All three, however, are [35] connected with passages leading in the direction of the lung, but all these communications are indistinctly discernible by reason of their minuteness, except [513b1] one.

  The great vein, then, is attached to the biggest of the three chambers, the one that lies uppermost and on the right-hand side; it then extends right through the chamber, coming out as a vein again; just as though the cavity were a part of the vessel, in which the blood forms a lake. The aorta is attached to the middle [5] chamber; but the arrangement is dissimilar, and it is connected with it by a much narrower pipe.

  The vein then passes through the heart and a passage runs from the heart into the aorta. The great vein looks as though made of membrane or skin, while the aorta is narrower than it, and is very sinewy; and as it stretches away to the head and to [10] the lower parts it becomes exceedingly narrow and sinewy.

  First of all, then, upwards from the heart there stretches a part of t
he great vein towards the lung and the attachment of the aorta, a large undivided vessel. But there split off from it two parts; one towards the lung and the other towards the [15] backbone and the last vertebra of the neck.

  The vein that extends to the lung, as the lung itself is duplicate, divides at first into two; and then extends along by every pipe and every perforation, greater along the greater ones, lesser along the less, so that it is impossible to discern a single part [20] wherein there is not both perforation and vein; for the extremities are indistinguishable from their minuteness, and the whole lung appears to be filled with blood. The passages from the vein lie above the tubes that extend from the windpipe. And the vein which extends to the vertebra of the neck and the backbone, stretches back [25] again along the backbone; as Homer represents in the lines:—

  He cut through all that vein

  which runs along the back right to the neck.10

  [30] From this vessel there extend small veins past each rib and each vertebra; and at the vertebra above the kidneys the vessel bifurcates. And in the above way the parts branch off from the great blood-vessel.

  But up above all these, from that part which is connected with the heart, the entire vein branches off in two directions. The one set extend to the sides and to the collar-bones, and then pass on through the armpits, in men to the arms, in [514a1] quadrupeds to the forelegs, in birds to the wings, and in fishes to the upper fins. The origins of these veins, where they first branch off, are called the jugular veins; and [5] where they branch off to the neck they run alongside the windpipe; and, occasionally, if these veins are pressed externally, men, though not actually choked, become insensible, shut their eyes, and fall to the ground. Extending in the way described and keeping the windpipe in between them, they pass on until they reach the ears at [10] the junction of the lower jaw with the skull. Hence again they branch off into four veins, of which one bends back and descends through the neck and the shoulder, and meets the previous branching off of the vein at the bend of the arm, while the rest of it terminates at the hand and fingers.