The Natural Faculties

All the arteries possess a power which derives from the heart, and by virtue of which they dilate and contract.

Put together, therefore, the two facts—that the arteries have this motion, and that everything, when it dilates, draws neighbouring matter into itself—and you will find nothing strange in the fact that those arteries which reach the skin draw in the outer air when they dilate, while those which anastomose at any point with the veins attract the thinnest and most vaporous part of the blood which these contain, and as for those arteries which are near the heart, it is on the heart itself that they exert their traction.

For, by virtue of the tendency by which a vacuum becomes refilled, the lightest and thinnest part obeys the tendency before that which is heavier and thicker. Now the lightest and thinnest of anything in the body is firstly pneuma, secondly vapour, and in the third place that part of the blood which has been accurately elaborated and refined.

These, then, are what the arteries draw into themselves on every side; those arteries which reach the skin draw in the outer air390 (this being near them and one of the lightest of things); as to the other arteries, those which pass up from the heart into the neck, and that which lies along the spine, as also such arteries as are near these—draw mostly from the heart itself; and those which are further from the heart and skin necessarily draw the lightest part of the blood out of the veins. So also the traction exercised by the diastole of the arteries which go to the stomach and intestines takes place at the expense of the heart itself and the numerous veins in its neighbourhood; for these arteries cannot get anything worth speaking of from the thick heavy nutriment contained in the intestines and stomach,391 since they first become filled with lighter elements. For if you let down a tube into a vessel full of water and sand, and suck the air out of the tube with your mouth, the sand cannot come up to you before the water, for in accordance with the principle of the refilling of a vacuum the lighter matter is always the first to succeed to the evacuation.

Chapter 15

Only a very little nutrient matter gets from the stomach into the arteries.

This is because these first become filled with lighter matter.

There are 2 kinds of attraction, that by which a vacuum becomes refilled and that caused by appropriateness of quality;392 air is drawn into bellows in one way, and iron by the lodestone in another.

The traction which results from evacuation acts primarily on what is light, whilst that from appropriateness of quality acts frequently, it may be, on what is heavier (if this should be naturally more nearly related393).

Therefore, in the case of the heart and the arteries, it is in so far as they are hollow organs, capable of diastole, that they always attract the lighter matter first, while, in so far as they require nourishment, it is actually into their coats (which are the real bodies of these organs) that the appropriate matter is drawn.394

Of the blood, then, which is taken into their cavities when they dilate, that part which is most proper to them and most able to afford nourishment is attracted by their actual coats.

Now, apart from what has been said,395 the following is sufficient proof that something is taken over from the veins into the arteries. If you will kill an animal by cutting through a number of its large arteries, you will find the veins becoming empty along with the arteries: now, this could never occur if there were not anastomoses between them.

Similarly, also, in the heart itself, the thinnest portion of the blood is drawn from the right ventricle into the left, owing to there being perforations in the septum between them: these can be seen for a great part [of their length]; they are like a kind of fossae [pits] with wide mouths, and they get constantly narrower; it is not possible, however, actually to observe their extreme terminations, owing both to the smallness of these and to the fact that when the animal is dead all the parts are chilled and shrunken.396

Here, too, however, our argument,397 starting from the principle that nothing is done by Nature in vain, discovers these anastomoses between the ventricles of the heart; for it could not be at random and by chance that there occurred fossae ending thus in narrow terminations.

And secondly [the presence of these anastomoses has been assumed] from the fact that, of the two orifices in the right ventricle, the one conducting blood in and the other out, the former398 is much the larger. For, the fact that the insertion of the vena cava into the heart399 is larger than the vein which is inserted into the lungs400 suggests that not all the blood which the vena cava gives to the heart is driven away again from the heart to the lungs.

Nor can it be said that any of the blood is expended in the nourishment of the actual body of the heart, since there is another vein401 which breaks up in it and which does not take its origin nor get its share of blood from the heart itself. And even if a certain amount is so expended, still the vein leading to the lungs is not to such a slight extent smaller than that inserted into the heart as to make it likely that the blood is used as nutriment for the heart: the disparity is much too great for such an explanation. It is, therefore, clear that something is taken over into the left ventricle.402

Moreover, of the two vessels connected with it, that which brings pneuma into it from the lungs403 is much smaller than the great outgrowing artery404 from which the arteries all over the body originate; this would suggest that it not merely gets pneuma from the lungs, but that it also gets blood from the right ventricle through the anastomoses mentioned.

Now it belongs to the treatise “On the Use of Parts” to show that it was best that some parts of the body should be nourished by pure, thin, and vaporous blood, and others by thick, turbid blood, and that in this matter also Nature has overlooked nothing. Thus it is not desirable that these matters should be further discussed.

Having mentioned, however, that there are two kinds of attraction, certain bodies exerting attraction along wide channels during diastole (by virtue of the principle by which a vacuum becomes refilled) and others exerting it by virtue of their appropriateness of quality, we must next remark that the former bodies can attract even from a distance, while the latter can only do so from among things which are quite close to them; the very longest tube let down into water can easily draw up the liquid into the mouth, but if you withdraw iron to a distance from the lodestone or corn from the jar (an instance of this kind has in fact been already given405) no further attraction can take place.

This you can observe most clearly in connection with garden conduits. For a certain amount of moisture is distributed from these into every part lying close at hand but it cannot reach those lying further off: therefore one has to arrange the flow of water into all parts of the garden by cutting a number of small channels leading from the large one.

The intervening spaces between these small channels are made of such a size as will, presumably, best allow them [the spaces] to satisfy their needs by drawing from the liquid which flows to them from every side. So also is it in the bodies of animals. Numerous conduits distributed through the various limbs bring them pure blood, much like the garden water-supply, and, further, the intervals between these conduits have been wonderfully arranged by Nature from the outset so that the intervening parts should be plentifully provided for when absorbing blood, and that they should never be deluged by a quantity of superfluous fluid running in at unsuitable times.

For the way in which they obtain nourishment is somewhat as follows. In the body406 which is continuous throughout, such as Erasistratus supposes his simple vessel to be, it is the superficial parts which are the first to make use of the nutriment with which they are brought into contact; then the parts coming next draw their share from these by virtue of their contiguity; and again others from these; and this does not stop until the quality of the nutrient substance has been distributed among all parts of the corpuscle in question. And for such parts as need the humour which is destined to nourish them to be altered still further, Nature has provided a kind of storehouse, either in the form of a central cavity or else as separate caverns,407 or something analogous to caverns. Thus the flesh of the viscera and of the muscles is nourished from the blood directly, this having undergone merely a slight alteration; the bones, however, in order to be nourished, require very great change, and what blood is to flesh marrow is to bone; in the case of the small bones, which do not possess central cavities, this marrow is distributed in their caverns, whereas in the larger bones which do contain central cavities the marrow is all concentrated in these.

For, as was pointed out in the first book,408 things having a similar substance can easily change into one another, whereas it is impossible for those which are very different to be assimilated to one another without intermediate stages. Such a one in respect to cartilage is the myxoid substance which surrounds it, and in respect to ligaments, membranes, and nerves the viscous liquid dispersed inside them; for each of these consists of numerous fibres, which are homogeneous409—in fact, actual sensible elements; and in the intervals between these fibres is dispersed the humour most suited for nutrition; this they have drawn from the blood in the veins, choosing the most appropriate possible, and now they are assimilating it step by step and changing it into their own substance.

All these considerations, then, agree with one another, and bear sufficient witness to the truth of what has been already demonstrated; there is thus no need to prolong the discussion further. For, from what has been said, anyone can readily discover in what way all the particular [vital activities] come about. For instance, we could in this way ascertain why it is that in the case of many people who are partaking freely of wine, the fluid which they have drunk is rapidly absorbed410 through the body and almost the whole of it is passed by the kidneys within a very short time. For here, too, the rapidity with which the fluid is absorbed depends on appropriateness of quality, on the thinness of the fluid, on the width of the vessels and their mouths, and on the efficiency of the attractive faculty.

The parts situated near the alimentary canal, by virtue of their appropriateness of quality, draw in the imbibed food for their own purposes, then the parts next to them in their turn snatch it away, then those next again take it from these, until it reaches the vena cava, whence finally the kidneys attract that part of it which is proper to them. Thus it is in no way surprising that wine is taken up more rapidly than water, owing to its appropriateness of quality, and, further, that the white clear kind of wine is absorbed more rapidly owing to its thinness, while black turbid wine, is checked on the way and retarded because of its thickness.

These facts, also, will afford abundant proof of what has already been said about the arteries; everywhere, in fact, such blood as is both specifically appropriate and at the same time thin in consistency answers more readily to their traction than does blood which is not so; this is why the arteries which, in their diastole, absorb vapour, pneuma, and thin blood attract either none at all or very little of the juices contained in the stomach and intestines.

299 “Of food to feeder,” i.e. of the environment to the organism. cf. p. 39, chap. xi.

300 “Drawing”; cf. p. 116, note 2.

301 For these terms (prosthesis and prosphysis in Greek) cf. p. 39, notes 5 and 6.

302 Lit. “through the energizing (or functioning) of the attractive faculty”; the faculty (δύναμις) in operation is an activity (ἐνέργεια). cf. p. 3, note 2.

303 This chapter is an excellent example of Galen’s method of reasoning a priori. The complementary inductive method, however, is employed in the next chapter. cf. p. 209, note 1.

304 The deductive.

305 The logos is the argument or “theory” arrived at by the process of λογικὴ θεωρία or “theorizing”; cf. p. 151, note 3; p. 205, note 1.

306 The Greek words for the uterus (mêtrae and hysterae) probably owe their plural form to the belief that the organ was bicornuate in the human, as it is in some of the lower species.

307 Note this expression. For Galen’s views on the origin of species, cf. Introduction, p. xxxi., footnote.

308 Herophilus of Chalcedon (circa 300 B.C.) was, like Erasistratus, a representative of the anatomical school of Alexandria. His book on Midwifery was known for centuries. cf. Introduction, p. xii.

309 Relaxation of utero-sacral ligaments as an important predisposing cause of prolapsus uteri.

310 That is, at the end of the first stage of labour.

311 The pylorus.

312 “Chylosis,” chylification. cf. p. 240, note 1.

313 Lit. barley-“chyle,” i.e. barley-water.

314 i.e. not the mere mechanical breaking down of food, but a distinctively vital action of “alteration.”

315 Pepsis.

316 Book I., chaps. x., xi.

317 cf. p. 222, note 1.

318 Choledochous.

319 More exactly peristolé; cf. p. 97, note 1.

320 Neuburger says of Erasistratus that “dissection had taught him to think in terms of anatomy.” It was chiefly the gross movements or structure of organs with which he concerned himself. Where an organ had no obvious function, he dubbed it “useless”; e.g. the spleen (cf. p. 143).

321 i.e. contracting and dilating; no longitudinal movements involved; cf. p. 263, note 2.

322 cf. p. 282, note 1.

323 Book II., chaps. ii. and viii.

324 Note use of psychological terms in biology. cf. also p. 133, note 3.

325 “In everything.” cf. p. 66, note 3.

326 Galen confuses the nutrition of organs with that of the ultimate living elements or cells; the stomach does not, of course, feed itself in the way a cell does. cf. Introduction, p. xxxii.

327 cf. Asclepiades’s theory regarding the urine, p. 51.

328 The process of application or prosthesis. cf. p. 223, note 3.

329 Mutual influence of organism and environment.

330 Qualitative change. cf. Book I., chap. ii.

331 Apparently skin-diseases in which a superficial crust (resembling the lichen on a tree-trunk) forms—e.g. psoriasis.

332 Note especially pneuma and innate heat, which practically stand for oxygen and the heat generated in oxidation. cf. p. 41, note 3.

333 Book I., chap. x.

334 That is to say, faeces are obviously altered food. This alteration cannot have taken place entirely in the small intestine: therefore alteration of food must take place in the stomach.

335 cf. p. 39.

336 Asclepiades held that there was no such thing as real qualitative change; the food was merely broken up into its constituent molecules, and absorbed unaltered. cf. p. 49, note 5.

337 i.e. denial of forethought in the Physis.

338 v. p. 9, et passim.

339 cf. p. 97.

340 It appears to me, from comparison between this and other passages in Galen’s writings (notably Use of Parts, iv., 8), that he means by the “two coats” simply the mucous and the muscular coats. In this case the “straight” or “longitudinal” fibres of the inner coat would be the rugae; the “circular” fibres of the inner intestinal coat would be the valvulae conniventes.

341 The term here rendered peristalsis is peristolé in Greek; it is applied only to the intermittent movements of muscles placed circularly round a lumen or cavity, and comprehends systolé or contraction and diastolé or dilatation. In its modern significance, peristalsis, however, also includes the movements of longitudinal fibres. cf. p. 97, note 1.

342 i.e. those containing non-striped or “involuntary” muscle fibres; organs governed by the “natural” pneuma; cf. p. 186, note 3.

343 By this term is meant only what we should call the “voluntary” muscles.

344 cf. p. 97.

345 For “symptom,” cf. p. 13, and p. 12, note 3. “Transitum namque materiae per angustum corpus id accidens consequitur” (Linacre). Less a “result” or “consequence” than an “accompaniment.”

346 i.e. this is a purely mechanical process.

347 i.e.. this phenomenon is a proof neither of peristolé nor of attraction. cf. p. 97, note 2.

348 Contraction and dilatation of course being reversed.

349 The channa is a kind of sea-perch; “a species of Serranus, either S. scriba or S. cabrilla” (D’Arcy W. Thompson). cf. Aristotle’s Nat. Hist. (D’Arcy Thompson’s edition, Oxford, 1910), IV., xi., 538 A, 20. The synodont “is not to be identified with certainty, but is supposed to be Dentex vulgaris,” that is, an edible Mediterranean perch. “It is not the stomach,” adds Prof. Thompson, “but the air-bladder that gets everted and hangs out of the mouth in fishes, especially when they are hauled in from a considerable depth.” cf. H. A., VIII., ii., 591 B, 5.

350 Under the term “neura,” tendons were often included as well as nerves. Similarly in modern Dutch the word zenuw (“sinew”) means both a tendon and a nerve; zenuwachtig = “nervous.”

351 Rather than the alternative reading, τὸν ἔσωθεν χιτῶνα. Galen apparently supposes that the outer coat will not be damaged, as the cuts will pass between its fibres. These cuts would be, presumably, short ones, at various levels, no single one of them involving the whole circumference of the gullet.

352 cf. p. 205.

353 Thus Galen elsewhere calls the spleen a mere emunctory (ἐκμαγεῖον) of the liver. cf. p. 214, note 1.

354 cf. p. 269.

355 The urinary bladders of pigs (such as Galen dissected) are thin, and appear to have only one coat.

356 cf. p. 243.

357 My suggestion is that Galen refers to (1) the mucous coat, with its valvulae conniventes, and (2) the muscular coat, of which the chief layer is made up of circular fibres. cf. p. 262, note 1.

358 Or utility.

359 Relationship between physiology and pathology again emphasized. cf. p. 188, note 2.

360 Or physicist—the investigator of the Physis or Nature. cf. p. 196, note 2. Note here the use of analogical reasoning. cf. p. 113, note 2.

361 cf. p. 95.

362 I. xiii.; II. ii.

363 Galen’s idea is that if reversal of the direction of flow can occur in the primae viae (in vomiting), it may also be expected to occur in the secundae viae or absorptive channels.

364 For this “delivery,” “up-yield,” or anadosis, v. p. 13, note 5.

365 The mesenteric veins.

366 Linacre renders: “Una omnium confluxio ac conspiratio”; and he adds the marginal note “Totum corpus nostrum est conspirabile et confluxile per meatus communes.” cf. p. 48.

367 The alimentary canal, as not being edible, is not considered a splanchnon or viscus.

368 Lit. rheums; hence our term rheumatism.

369 Here Galen apparently indicates that vital functions are at least partly explicable in terms of mechanical law. cf. Introduction, p. xxviii.

370 cf. pp. 211, 247.

371 See p. 298, note 1.

372 The ends of the veins in the alimentary canal from which absorption or anadosis had originally taken place.

373 Diathesis.

374 Diathesis.

375 Pathos.

376 He means, not only under the stress of special circumstances, but also normally.

377 Lit. “rough artery.” The air-passages as well as the arteries proper were supposed by the Greeks to carry air (pneuma); diastole of arteries was, like expansion of the chest, a movement for drawing in air. cf. p. 317, note 1.

378 cf. p. 39, chap. xi.

379 Lit. orexis.

380 Lit. a “physical” organ; that is, a mere instrument or organon of the Physis,—not one of the Psyche or conscious personality. cf. semen, p. 132, note 1.

381 cf. p. 317, note 2; p. 319, chap. xv.

382 Note that absorption takes place from the stomach as well as the intestines. cf. p. 118, note 1.

383 That is, among the ultimate tissues or cells.

384 Pp. 205-9.

385 By this term, of course, the air-passages are also meant; cf. p. 305.

386 cf. p. 34, note 1.

387 cf. p. 121, note 4.

388 Pulmonary vein, or rather, left auricle. Galen means a reflux through the mitral orifice; the left auricle was looked on rather as the termination of the pulmonary veins than as a part of the heart. cf. p. 323, note 4. He speaks here of a kind of “physiological” mitral incompetence.

389 Horror vacui.

390 cf. p. 305, note 2.

391 cf. p. 308, note 1.

392 The “mechanical” principle of horror vacui contrasted with the “physical” or semi-physiological principle of specific attraction. Appropriateness here might almost be rendered affinity or kinship. cf. note 2, infra.

393 “Related,” “akin.” cf. p. 36, note 2.

394 The coats exercise the vital traction, the cavities the merely mechanical. cf. p. 165, note 2.

395 Chap. xiv.

396 These fossae were probably the recesses between the columnae carnae.

397 On logos cf. p. 226, note 2.

398 He means the tricuspid orifice. cf. p. 121, note 4.

399 The right auricle was looked on less as a part of the heart than as an expansion or “insertion” of the vena cava.

400 This “vein” (really the pulmonary artery) was supposed to be the channel by which the lungs received nutriment from the right heart. cf. p. 121, note 3.

401 The coronary vein.

402 Galen’s conclusion, of course, is, so far, correct, but he has substituted an imaginary direct communication between the ventricles for the actual and more roundabout pulmonary circulation, of whose existence he apparently had no idea. His views were eventually corrected by the Renascence anatomists. cf. Introduction, pp. xxii.-xxiii.

403 He means the left auricle, considered as the termination of the pulmonary “arteries”; cf. p. 314, note 3.

404 The aorta, its orifice being circular, appears bigger than the slit-like mitral orifice.

405 p. 87.

406 Or we may render it “corpuscle”; Galen practically means the cell. cf. p. 153, note 2.

407 cf. the term “cavernous tissue.”

408 I. x.

409 Lit. homoeomerous, i.e. “the same all through,” of similar structure throughout, the elements of living matter, cf. p. 20, note 3, and cf. also the “cell” of Erasistratus, p. 153.

410 “Delivered,” “dispersed”; cf. p. 13, note 5.