BEFORE AND AFTER BIRTH. 403 



allows a great increase to the capacity of the chest ; not only 

 is full inspiration allowed, and consequently a free passage to the 

 blood of the pulmonary vessels during inspiration, as Haller re- 

 marks,* but a certain degree of permanent dilatation of the 

 lungs is allowed (for much air remains in the lungs after every 

 expiration), and as the liver contains, immediately after birth, so 

 much smaller a portion of the blood of the system than before, 

 the greatly increased supply required by the lungs is thus afforded, f 

 See Note B. Sect. VIII. 



* Elementa Physiologies. T. 8. 



t See Mr. Bryce's ingenious paper on this subject in the Edinburgh Med. 

 and Surg. Journal. 1815. Jan. 



2d2 



