VIII. ] ERRORS ATTRIBUTED TO ARISTOTLE. 183 



the head and the lower parts it becomes narrow and altogether 

 tendinous. 



(P) "In the first place, a part of the great vein extends 

 upwards from the heart towards the lung and the attachment of 

 the aorta, the vein being large and undivided. It divides into 

 two parts, the one to the lung, the other to the spine and the 

 lowest vertebra of the neck. 



(Q) " The vein which extends to the lung first divides into 

 two parts for the two halves of it and then extends alongside 

 each tube (a-vpiyya) and each passage (rp^a), the larger beside 

 the larger and the smaller beside the smaller, so that no part 

 [of the lung] can be found from which a passage (lywj/Aa) and a 

 vein are absent. The terminations are invisible on account of 

 their minuteness, but the whole lung appears full of blood. The 

 canals from the vein lie above the tubes given off from the 

 windpipe." 



The key to the whole of the foregoing description 

 of the heart lies in the passages (G) and (L). They 

 prove that Aristotle, like Galen, five hundred years 

 afterwards, and like the great majority of the old 

 Greek anatomists, did not reckon what we call the 

 right auricle as a constituent of the heart at all, but 

 as a hollow part, or dilatation, of the " great vein." 

 Aristotle is careful to state that his observations were 

 conducted on suffocated animals ; and if any one will 

 lay open the thorax of a dog or a rabbit, which has 

 been killed with chloroform, in such a manner as to 

 avoid wounding any important vessel, he will at once 

 see why Aristotle adopted this view. 



For, as the subjoined figure (p. 185) shows, the 

 vena cava inferior (6), the right auricle (R.a.), and 

 the vena cava superior and innominate vein (F.7.) 

 distended with blood seem to form one continuous 

 column, to which the heart is attached as a sort 



