NATURE 



[Nov. 6, 1879 



" 'S.vvrjpreTai de Kai r) KapSia rij apTt)piq iript\i>heai Ka\ )(ov- 

 8/«iSf(Tt Kai Ivw&hti Beo-po'if y 8e o-vvrjpriTat, ko'CKuv etmv. 

 <j>vo-o>pevr)t be Trjs aprripias ev evlois piv nv KarddrjXov noui, tv 

 8e rots pcii^otn twv (aScov Sr/Xov on elo-ep\(ral to irvevpa (h 

 ain)v" (i. cap. 16). 



" The heart and the windpipe are connected by fatty and 

 cartilaginous and fibrous bands ; where they are connected 

 it is hollow. Blowing into the windpipe does not show 

 clearly in some animals, but in the larger animals it is 

 clear that the air goes into it." 



Aubert and Wimmer give a somewhat different render- 

 ing of this passage : — 



" Auch das Herz hiingt mit der Luftiohre dutch fett- 

 reiche, knorpelige und faserige Bander zusammen ; und 

 da, wo sie zusammenhangen, ist eine Hdhlung. Beim 

 Autblasen der Lunge wird es bei manchen Thieren nicht 

 wahrnehmbar, bei den grosseren aber ist es offenbar, dass 

 die Luft in das Herz gelangt." 



The sense here turns upon the signification which is to 

 be ascribed to us ceMjv. But if these words refer to the 

 heart, then Aristotle has distinctly pointed out the road 

 which the air, in his opinion, takes, namely, through the 

 " synapses " ; and there is no reason that I can discover 

 to believe that he "postulated " any other and more direct 

 communication. 



With respect to the meaning of koXKov io-nv, Aubert and 

 Wimmer observe : — 



" Dies scheint wohl die kurze Lungenvene zu sein. 

 Schneider bezieht dies auf die Vorkammern, allein diese 

 werden unten als Hohlen des Herzens beschrieben." 



I am disposed to think, on the contrary, that the 

 words refer simply to the cavity of the pericardium. For 

 a part of this cavity {sinus transversus pericardii) lies 

 between the aorta, on the one hand, and the pulmonary 

 vessels with the bifurcation of the trachea, on the other 

 hand, and is much more conspicuous in some animals 

 than in man. It is strictly correct, therefore, in Aristotle's 

 words, to say that where the heart and the windpipe are 

 connected " it is hollow." If he had meant to speak of 

 one of the pulmonary veins, or of any of the cavities 

 of the heart, he would have used the terms n&poi or koiKIcis 

 which he always employs for these parts. 



According to Aristotle, then, the air taken into the lungs 

 passes from the final ramifications of the bronchial tube s 

 into the corresponding branches of the pulmonary blood 

 vessels, not through openings, but by transudation, or, as 

 we should nowadays say, diffusion, through the thin 

 partitions formed by the applied coats of the two sets of 

 canals. But the "pneuma" which thus reached the 

 interior of the bloodvessels was not, in Aristotle's opinion, 

 exactly the same thing as the air. It was "m)p 7ro\is 

 ptav k«i adpios" (" De Mundo," iv., 9) — subtilized and 

 condensed air ; and it is hard to make out whether 

 Aristotle considered it to possess the physical properties 

 of a gas or those of a liquid. As he affirms that all the 

 cavities of the heart contain blood (/), it is clear that he 

 did not hold the erroneous view propounded in the next 

 generation by Erasistratus. On the other hand, the fact 

 that he supposes that the spermatic arteries do not contain 

 blood but only an m/jaraoV vypov (" Hist. Animalium," 

 iii., 1), shows that his notions respecting the contents of 

 the arteries were vague. Nor does he seem to have 

 known that the pulse is characteristic only of the arteries; 

 and as he thought that the arteries end in solid fibrous 

 bands, he naturally could not have entertained the faintest 



conception of the true motion of the blood. But without 

 attempting to read into Aristotle modern conceptions 

 which never entered his mind, it is only just to observe 

 that his view of what becomes of the air taken into the 

 lungs is by no means worthy of contempt as a gross 

 error. On the contrary, here, as in the case of his 

 anatomy, what Aristotle asserts is true as far as it goes. 

 Something does actually pass from the air contained in 

 the lungs through the coats of the vessels into the blood, 

 and thence to the heart ; to wit, oxygen. And I think 

 that it speaks very well for ancient Greek science that the 

 investigator of so difficult a physiological problem as that 

 of respiration, should have arrived at a conclusion, the 

 statement of which, after the lapse of more than two 

 thousand years, can be accepted as a thoroughly estab- 

 lished scientific truth. 



I trust that the case in favour of removing the statements 

 about the heart, from the list of the " errors of Aristotle " 

 is now clear ; and that the evidence proves, on the 

 contrary, that they justify us in forming a very favourable 

 estimate of the oldest anatomical investigations among 

 the Greeks of which any sufficient record remains. 



But is Aristotle to be credited with the merit of having 

 ascertained so much of the truth ? This question will not 

 appear superfluous to those who are acquainted with the 

 extraordinary history of Aristotle's works, or who adopt 

 the conclusion of Aubert and Wimmer, that, of the ten 

 books of the " Historia Animalium" which have come 

 down to us, three are largely or entirely spurious and 

 that the others contain many interpolations by later 

 writers . 



It so happens, however, that, apart from other reasons, 

 there are satisfactory internal grounds for ascribing the 

 account of the heart to a writer of the time at which 

 Aristotle lived. For, within thirty years of his death, the 

 anatomists of the Alexandrian school had thoroughly 

 investigated the structure and the functions of the valves 

 of the heart. During this time, the manuscripts of 

 Aristotle were in the possession of Theophrastus ; and no 

 interpolator of later date would have shown that he was 

 ignorant of the nature and significance of these important 

 structures, by the brief and obscure allusion — " in its 

 cavities there are tendons (a)." On the other hand, 

 Polybus, whose account of the vascular system is quoted 

 in the " Historia Animalium " was an elder contemporary 

 of Aristotle. Hence, if any part of the work faithfully 

 represents that which Aristotle taught, we may safely 

 conclude that the description of the heart does so. 

 Having granted this much, however, it is another question, 

 whether Aristotle is to be regarded as the first discoverer 

 of the facts which he has so well stated, or whether he, 

 like other men, was the intellectual child of his time and 

 simply carried on a step or two the work which had been 

 commenced by others. 



On the subject of Aristotle's significance as an original 

 worker in biology extraordinarily divergent views have 

 been put forward. If we are to adopt Cuvier's estimate, 

 Aristotle was simply a miracle : — 



" Avant Aristote la philosophic, entierement speculative, 

 se perdait dans les abstractions depourvues de fondement ; ■ 

 la science n'existait pas. II semble quelle soit sortie 

 toute faite du cerveau d' Aristote comme Minerve, toute 

 armee, du cerveau de Jupiter. Seul, en effet, sans ante- 

 cedents, sans rien emprunteraux siecles qui l'avaient pr£ 



