SECT. XVI. PHYSIOLOGY. 125 
cexcv. The expansibility of the pulmonary air- 
cells, is known to depend on the vital force, 
by dividing the nerves distributed upon them. 
When the par vagum of a dog is divided in both 
sides of the neck, the lungs are paralyzed; or, in 
other words, their expansibility is impaired; the 
muscles of inspiration dilate the thorax with vio- 
lence; but the air which enters the lungs, is 
inconsiderable in quantity; the expirations are 
hurried, and the animal dies of asphixia. 
cexcvi. The division of the par vagum does 
not cause complete paralysis of the lungs, as they 
derive part of their nervous influence from the 
first thoracic ganglion of the great sympathetic ; 
but it always impairs their expansibility suffi- 
ciently to cause death. 
cexcvul. The asthma of medical authors, ap- 
pears to be simply impaired expansibility of the 
air-cells, which may, according to Dr. Philips, be 
restored for a while, by sending a current of 
galvanic electricity through the thorax; opium, 
ether, and asafeetida, have often a similar tem- 
porary effect. 
ccxcvul. Some years ago, I had occasion to 
treat a gentleman severely afflicted with asthma; 
I exhausted his patience by a tedious administra- 
tion of antispasmodics, but with no permanent 
advantage, and the disease at last threatened 
