( >.<55 ) 
If we confider the State of the Blood at its Return 
to the Heart, and how careful Nature has been, not to 
ufe this Blood for the Nourifhment of the Lungs be* 
fore it has palTed through the pulmonary Vein and Ar- 
tery (though it would in that Cafe have been as effedu- 
allycooled in the Bronchial Arteries as in the pulmona- 
ry VefTels).we are naturally led to believe, that it is 
fome other Quality which has rendred it improper for 
Nourifhment, and which is to be deftroyed by the 
Adion of the Lungs. 
I have before allowed, that it feems almofl evident 
that the Blood is cooled, and of Confequence condenf- 
. ed in the Adion of Infpiration ; but for the Reafon 
mentioned, and from confidering the Strudure of the 
Parts fubfervient to breathing, it feems equally true, 
that the Blood is mixed, attenuated, and confequently 
re-expanded in the Adion of Expiration. I fhall now 
confider whether the Adion of Infpiration fo far over- 
balances the Adion of Exfpiration, as to condenfe the 
Blood into a lefs Bulk than it had before its Paffage 
through the Lungs. 
The Santorini of Fenice^ in the 8th Chap- 
ter and 3d Sedion of his Obfervations, has carefully 
examined the Fad as dated by Monf. Helvetius ; 
. and finding it true in that one Subjed, as to the Au- 
] rides and pulmonary Veffels, but falfe as to the Ven- 
I tricks, he proceeds to prove that this Difference in 
I the Capacity of the pulmonary Veffels, could not be 
defigned on Account of the Blood’s being condenfed 
i in its Paffage through the Lungs , becaufe, if fo, the 
1 right Ventricle ought to have been larger than the left 
Ventricle ^ and the pulmonary Artery ouglix, not on- 
lly to have been larger than the pulmonary Veins, 
but 
