and functions of the nerves. 413 
pain ; there was no struggle nor effort made when it was cut 
across. 
The animal being untied and corn and hay given to him, 
he eat without the slightest impediment. 
An ass being tied and thrown, the superior maxillary 
branch of the fifth nerve was exposed Touching this nerve 
gave acute pain. It was divided, but no change took place 
in the motion of the nostril ; the cartilages continued to ex- 
pand regularly in time with the other parts which combine 
in the act of respiration ; but the side of the lip was observed 
to hang low, and it was dragged to the other side. The same 
branch of the fifth was divided on the opposite side, and the 
animal let loose. He could no longer pick up his corn ; the 
power of elevating and projecting the lip, as in gathering 
food, was lost. To open the lips the animal pressed the 
mouth against the ground, and at length licked the oats from 
the ground with his tongue. The loss of motion of the lips 
in eating was so obvious, that it was thought a useless cruelty 
to cut the other branches of the fifth. 
This experiment of cutting the respiratory nerve of the 
face, or portio dura, gave so little pain, that it was several 
times repeated on the ass and dog, and uniformly with the 
same effect. The side of the face remained at rest and placid, 
during the highest excitement of the other parts of the re- 
spiratory organs. 
When the ass, on which the respiratory nerve of the 
face had been cut, was killed, which was done by bleeding, 
an unexpected opportunity was offered of ascertaining its 
influence, by the negation of its powers on the side of the 
face where it was cut across. 
