OF THE MOUTH. 277 



acutely sensible to touch. But all this never 

 moves our surprise or admiration. 



If we know any thing of muscularity, we must 

 presume that there is a concourse of fine muscles 

 converging to the lips and surrounding them. But 

 what gives the lips their sensibility ? This was a 

 question early suggested to me in my investiga- 

 tions on the nerves ; when experiment showed 

 that one nerve went to the lips for sensation,^ and 

 another for motion. The vermilion surfaces of 

 the lips possess their exquisite sensibility through 

 minute and delicate villi, into which the extremi- 

 ties of the sensitive nerve are distributed : and 

 these, being covered only by a cuticle the most 

 thin and transparent, afford the ready instrument 

 of touch. We see how the child uses the lips, as 

 giving him his first information of the qualities of 

 bodies. 



It is certainly an unexpected thing to find that 

 two organizations totally distinct, combined in the 

 lips, should be necessary to the simplest act. If 

 the nerve of motion be cut and has lost its func- 

 tion, the animal puts its lips to the grains it feeds 

 upon, but cannot gather them. If the nerve of 

 sensation be injured, the animal presses its lips to 

 the food, but wants the sensibility by which the 

 motions of the lips should be directed. These 

 facts show that whilst sensibility and motion are 

 distinct faculties and depend upon different nerves, 

 they are necessarily combined for so simple an act 

 as taking the food into the mouth. We thus daily 

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