VIII.] ERRORS ATTRIBUTED TO ARISTOTLE. 185 



A dog having been killed by chloroform, enough of the right wall of 

 the thorax was removed, without any notable bleeding, to expose the 

 thoracic viscera. A carefully measured outline sketch of the parts in situ 

 was then made, and on dissection, twenty-four hours afterwards, the 

 necessary anatomical details were added. The woodcut is a faithfully 

 reduced copy of the drawing thus constructed ; and it represents the 

 relations of the heart and great vessels as Aristotle saw them in a suffocated 

 animal. 



All but the inner lobe of the right lung has been removed ; as well as the right 

 half of the pericardium and the right walls of the right auricle and ventricle. 

 It must be remembered that the thin transparent pericardial membrane 

 appears nothing like so distinct in nature. 



.&., Aristotle's "great vein"; F.7., right vena innominata and vena cava 

 superior ; b, the inferior vena cava ; R.a., the "hollow middle" part of the 

 great vein or the right auricle ; E.v', the prolongation of the cavity of the 

 right ventricle R.v towards the pulmonary artery ; tr, one of the tricuspid 

 valves ; PC, the pericardium ; I.sv, superior intercostal vein ; Az, vena 

 azygos ; P. A. , right pulmonary artery ; Br, right bronchus ; L, inner 

 lobe of the right lung ; (E, oesophagus ; Ao, descending aorta ; H, liver, in 

 section, with hepatic vein, vena portse, and gall-bladder, gb, separated by 

 the diaphragm, also seen in section, from the thoracic cavity. 



