Part 24

Also thou wilt see in the heart certain membranous parts like auricles, or rather like small ears, able to dilate or contract: these are contrived by nature in order that when overmuch blood or spirit is generated the heart can dilate so as to contain it; and also that the heart may contract when there is no such abundance.

And it is here that Galen asks, Why did not nature make the heart so large that it could contain every increase of blood or spirit without the addition of these membranes? Galen replies that this was first because the heart would have been too large and therefore too heavy; secondly, because as it is not always generating a great quantity of blood and spirit, if the heart had been too large, its cavity would usually have been empty: but these auricles dilate with the accumulation of blood or spirit, and contract with its decrease.

The heart is surrounded by a firm and nervous membrane, like a little house in which it is placed as in a tabernacle to defend it from accidents. This capsule is very dilated, that the heart in its dilations and movement may not be impeded thereby, and therefore nature made this capsule so that it should contain a certain dewy moisture with which the heart is bathed and moistened so that in its continual movement it should not become dry. For when this water be dried up, then the heart itself is desiccated, and emaciates and dries up all the body.

* * * * *

The description of the heart follows Mondino closely. Occasionally a phrase or two is reminiscent of Mondeville. The trite conception of the heart as a king in its necessarily central position was very frequently repeated by writers in the Middle Ages. To Harvey, who had a certain mediaeval element in his mentality, it seems to have appealed, and he used it in his Prelectiones Anatomiae, and chose it to introduce his great work on the circulation of the blood. The heart was similarly described as ‘flame-shaped’, because it was regarded as the source of animal heat. The idea that it is the first to live and the last to die comes from Aristotle. The bone in the heart also comes from Aristotle. The idea was quite familiar to mediaeval anatomists, who frequently endeavoured to identify the bone with the firm tissue around the orifices of the aorta and pulmonary artery. The reader may be reminded that a true ‘os cordis’ is in fact to be found in some mammalia.

Mondino, followed by Manfredi, describes the action of the heart and blood-vessels mainly according to the views of Galen, but without any very clear or connected statement. The ‘third ventricle’ especially has its origin in a misunderstanding.

This mythical structure is an attempt to combine the views of Aristotle and of Galen. Aristotle, who probably never dissected a human body, derived his anatomical conceptions largely from cold-blooded animals, in some of which the heart is provided with three cavities. He considered that the heart had three chambers, the largest being on the right, the smallest on the left, and one of intermediate size between the two. As far as they can be identified, the largest was the right ventricle plus the right auricle, the smallest or left chamber was the left auricle, while the intermediate cavity appears to have been the left ventricle.

Galen’s description differed altogether from that of Aristotle. He tells us expressly and somewhat contemptuously that ‘it is no marvel if Aristotle erred in many anatomical matters, a man who thought forsooth that the heart in the larger animals had three chambers’. Galen always describes the heart as having but two chambers, the right and left ventricles, a wholly subordinate part being assigned to the auricles. These latter were regarded as safety-valves, expanding to hold superfluous blood when the chambers of the heart to which they correspond become overfilled.

From the Roncioni MS. (Pisa 99) after Sudhoff.]

No third ventricle is described by Rhazes or Haly Abbas, but Avicenna, in his Canon, makes an effort to combine the views of Aristotle and Galen. Speaking of the anatomy of the heart (lib. iii, fen. xi, chap. 1) he describes the ventricular portion as follows: ‘In the heart are three cavities, two large, and a third as it were central in position. So that the heart has [a] a receptacle [the right ventricle] for the nutriment with which it nourishes itself--this nutriment is thick and firm like the substance of the heart; [b] a place where the pneuma is formed [the left ventricle], being engendered of the subtil blood; and [c], thirdly, a canal between the two.’ A somewhat similar account is given in Constantine’s translation of Isaac. The idea soon crept into European medicine, for in a Pisan MS. dating from the first half of the thirteenth century a crude figure of a three-chambered heart is to be found (Fig. 21).

The first translator of the Canon of Avicenna, Gerard of Cremona, whose work appeared towards the end of the twelfth century, improved on his original. ‘In it [the heart] are three ventricles; two are large, and the third as it were between, which Galen called the fovea or non-ventricular meatus, so that there may be a receptaculum for the thick and strong nourishment, like to the substance of the heart, with which it is nourished, and also a storehouse for the pneuma (spiritus) generated in it from the subtil blood. And between the two are channels or meatuses.’ Henri de Mondeville (died about 1320), by going direct to Galen, avoided some of the errors of Avicenna, with whom, however, he still describes three ventricles. Mondino does little but copy the Arabian, whom Manfredi also follows.

We may terminate our description of the mythical third ventricle by quoting from Bartholomew the Englishman. His encyclopaedia written about 1260 was translated into English in 1397, and printed by Thomas Berthelet in the 27th year of the reign of Henry VIII (1535), when Bartholomew’s work was still extremely popular. Berthelet’s rendering runs as follows:

‘And the hert hath ij holownesses, one in the left syde, that cometh sharpe: and one in the ryght side, that is within: And these two holownesses ben called the wombes of the hart. And betwene these two wombes is one hole, that some men call a veyne, other an holowe way. And this hole is brode afore the ryghte syde, and streyte afore the left syde. And that is nedefulle to make the bloode subtyll, that commeth from the ryght wombe to the lefte, and so the spirite of lyfe may be bredde the easelyer in the lefte wombe.’

In order to understand why all these authors invoked the existence of the third ventricle, regarded by some of them as a passage between the other two, we must turn to the physiological beliefs of the age. It must be recalled that before the demonstration of the circulatory movement of the blood a certain amount of communication was believed to exist between right and left ventricles. The complicated nature of the ventricular cavities and the intricacy of the columnae carneae promoted the idea of the presence of minute passages in the interventricular septum. Even so astute an observer as Leonardo da Vinci considered that ‘the ventricles are separated by a porous wall, through which the blood of the right ventricle penetrates into the left ventricle, and when the right ventricle shuts, the left opens and draws in the blood which the right one gives forth’ (Plate XXXVIIIb).

Although the third ventricle is described in all the twenty-five editions of Mondino, many of which are illustrated, they present no drawing of it except the wretched little diagram of J. A. Muelich (Johannes Adelphus) in 1513, which we here reproduce (Fig. 22). The confusion, however, to which the idea of a third ventricle gave rise influenced anatomy almost as late as the seventeenth century, and is illustrated in the anatomical figures of a late edition of Hans von Gersdorff (1556), where the trachea is actually shown opening into the left ventricle (Fig. 23). It was Vesalius who took the first great step towards the discovery of the circulation of the blood, by firmly maintaining that the interventricular septum was solid and contained neither passages nor intermediate ventricle.

VI. ITALIAN TEXT

MS. Canonici Ital. 237

Hyeronimi manfredi ad Magnificum & potentem dominum ac militem Iohannem Bentiuolum insequens opus de corporis humani anothomia exordium.

Omnis igitur qui in operum dei gloriosi intuitu delectatur, hic prudens et non inscipiens est: hic dignus homo: hic intellectu non caret. Cum igitur tua illustris Dominatio Iohannes bentiuole magnanimis praesenti anno ex sui qua solet humanitate ad cuiusdam hominis defuncti anothomiam uno semel uidere non fuerit dedignata ob sui intellectus dignitatem qui semper alta intelligere concupiscit, cumque tu opera tam naturae miranda in anothomizato incaepisti uidere corpore tunc haec intelligendi creuit animus tua digna [folio 2 verso] creuit uoluntas: Et me hyeronimum Manfredum ad hoc opus de anothomia intitulatum materno sermone tuo dignissimo nomini inscribere concitasti: (ut omnino sicut debeor) rem gratam tuae faciam dominationi: In hoc enim tui agnoui dignitatem intellectus, tui ingenii solertiam quod in rebus naturae mirandis tuum peruoluas intellectum. Hoc enim opusculum quantum melius potui ex uariis antiquorum uoluminibus exserpsi ac id abreuiaui: nec eumdem forte tenui ordinem ut illi: et ipsum materno composui sermone ut opus hoc delectabilius tuae sit magnificentie.

Accipe igitur magnifice et potens domine hoc opus de corporis humani anothomia tuo dignisimo nomini intitulatum, ea benignitate et humanitate, qua soles: et animo illari ac gratioso id accepta: qui satis tibi erit delectabile et perplacebit quia dignum est opus: Vale miles magnanimis, et solito ama.

Finis prohemii.

Li ligamenti sono etiam simili a nerui facti a ligare le iuncture de le osse e non li dette la natura sentimento como fece a li nerui & a le corde acio che per el molto mouimento e fricatione de le iuncture non doleseno.

Le Artarie sono de substantia neruosa & ligamentale in longo extense o concaue: ne le quale se contene el sangue sutilissimo & depurato et el spirito uitale el quale e mandato dal core a dare uita a tuti i membri: et hano origine da esso core: & impero hebeno doe tuniche acio chel sangue sutile & el spirito uitale non usisseno fuora.

Le vene sono simile a lartarie ma sono quiete e non se moueno, ma hano origine dal figato et in esse se contene el sangue grosso cum li altri humuri che non e cusi depurato ne [folio 3 verso] cusi sutile como e el sangue de le artarie: impero non li fece senon una tunicha: per che quelo sangue non era cosi sutile chel potesse penetrare fuora ne anche non bisognandose mouere non era suspitione de rompersi como ne le artarie che era neccessario a mouerse per refrigerare el core atrahendo laiere frigido & expellendo fuora li fumi caldi da esso.

Li panniculi sono composti e texuti de fili neruosi sutilissimi che non se posseno uedere e sono questi paniculi spissi e sutili e sono de molte manerie: Alcuni forno facti a continere o coprire a Alcuni membri e custodirli ne la sua figura e substantia como sono li paniculi che copreno el cerebro e molti altri di li quali poi diremo: Alcuni altri panniculi sono facti a suspendere uno membro a laltro como li rognoni sono aligati a laschina mediante uno certo paniculo: Alcuni altri paniculi sono facti acio che alcuni membri che non hano sentimento recceuano qualche sentimento per el panniculo: nel quale sono inuolti como sono el pulmone el figato la milza & i rognoni li quali sono priuati de sentimento impero la natura aciascuno di loro li fece uno panniculo doue fusseuo inuolti per la casone dicta.

Da poi tuti questi membra hauendo la natura ordito el corpo de lhomo de [folio 4 recto] li predicti bisogno reimpire le uacuita e reimpille de carne: Fece aduncha la natura la carne per reimpire le uacuita che rimangono da lorditura de nerui uene & altri membri dicti.

Praeterea e da sapere che la natura ha dato aciascuno di li predicti membri quatro uirtu. Una e uirtu atratiua per laquale ha ad atrahere el nutrimento suo a se del quale el membro se ha a nutricare: La seconda uirtu e digegtiua per laquale el nutrimento atrato se digerisse & conuertese ne la sustantia del membro: La terza uirtu si e retentiua per laquale el nutrimento atrato se retiene debito tempo acio che la uirtu digestiua possa perficere la sua operatione circha quello: La quarta uirtu e expulsiua laquale ha expellere le superfluita che se generano dal nutrimento ne la digestione.

Anche e da sapere che la natura nel corpo de lhuomo ha facto quatro membri principali como quatro signori et aciascuno di loro li ha dato una casa o uero uno palazo a sua custodia doue habite cum certe camare o uero stantie che hano aseruirli al suo bisogno: El primo membro principale e signore e el cerebro al quale li fece la natura el capo cum le sue circumstantie per suo habitaculo e dette a questo membro che lui fusse principio e radice de tuto el sentimento e moto de tuto el [folio 4 verso] corpo: dal quale tuti li altri membri recceueno el sentire: e el mouere, & a questo membri li dette etiam cinque uirtu cognoscitiue exteriore cio e li cinque sentimenti e cinque altre uirtu cognoscitiue interiore che deserueno a lo intellecto.