158 Sylvius and his Pupils. [lect. 



it passed into the venous system and whence mixed with the 

 blood it was carried by the vena cava to the heart. This 

 erroneous view (a retrograde step from the position taken up 

 by Vesalius) was disproved by Glisson, and later on, as we 

 have seen, more distinctly by Malpighi ; but Sylvius long clung 

 to it. It fitted into his general theory. " Chyle," he says, 

 "assumes the form of blood (a superficial initial change) 

 " owing to the bilious blood ascending to the heart meeting 

 " in the right auricle and especially in the right ventricle 

 " with the lymphatic blood (of the superior vena cava) with 

 " which the chyle is mixed, and so on account of the different 

 " or rather opposite disposition of each (kind of blood) in certain 

 " of their parts provoking an effervescence of great moment." 

 This is the initial change on the right side of the heart; 

 but " the chyle reaches (not the superficial form only, but) 

 " the ultimate perfection of blood through the continued and 

 " tempered effervescence, presently to be described, which by 

 " reason of the breathing of air takes place in the lungs, in the 

 " left auricle and ventricle of the heart, and in the large trunks 

 " of the aorta. By the energy and help of this effervescence we 

 " think that there bursts out and springs forth the vital fire 

 " (ignis vitalis), which by rarefying the more fatty and oily parts, 

 " not only of the chyle added to the blood, but of the blood 

 " itself, and by loosely uniting together at the same time all 

 " other parts, reduces the whole into a heterogeneous, homo- 

 "geneous mass, and so converts the chyle into true blood." 



All this is wordy and vague enough ; nor is he at all more 

 distinct when he dwells on that breathing of air which, as he 

 has just said, brings about the above changes. After giving a 

 fair description of the mechanics of respiration he goes on to 

 say, 



" By what power, however, or in what manner and way the 

 " inspired air so alters the blood is not equally clear. /, for my 

 " part, think that it is brought about by reason of there being 

 "dispersed in the air nitrous and subacid particles able to 

 "condense the rarefied and boiling blood and so to gently 

 "restrain its ebullition." 



Wordy and vague as his exposition is, we cannot however 



