FUNCTIONS OF NERVES. 4-17 



those of the other four senses than touch, the nerves of the 

 specific senses, feel little or no pain when mechanical stimulus 

 is applied ; and these generally have not, like those which furnish 

 and possess common touch or common sensibility, and perhaps all 

 those of the specific senses, a ganglion at a certain distance from 

 their origin. 11 There is Gasser's ganglion for the trigeminum, the 

 posterior and larger part of which, including the ophthalmic and 

 superior and inferior maxillary, gives sensibility to the face, and 

 even what common sensibility they possess to the nerves of the 

 specific senses and of motion ; while the anterior and smaller part 

 is not united with Gasser's ganglion, and is a nerve of motion to the 

 muscles of the lower jaw, and some others of the face. There is a 

 ganglion for each posterior nerve of the spinal chord. 1 The anterior 



h See Dr. Magendie's Precis de Physiol. t. i. p. 200. sq. ed. 3. 



1 The branch of the trigeminum unconnected with the ganglion was de- 

 clared to be a nerve of motion only, and to belong to the various muscles 

 of the lower jaw, by Dr. Paletta in 1784: and was, therefore, called nervus 

 masticatorius by Dr. Bellinger! in 1818. (Dissert, inaug. Taurini, 1818.) Dr. 

 O'Beirne has shown that the motor portion is more extensively distributed 

 in the muscles of the face ; that, after uniting with the inferior maxillary of 

 the ganglionic portion, so that the two are intimately mixed and all the sub- 

 sequent branches are compound nerves one of which becomes attached to the 

 superior branch of the facial, it is distributed to many muscles of the face besides 

 those of the lower jaw. He hence explains some instances of a certain loss of mo- 

 tion after injury of the ganglionic portion of the fifth, and of continuance of motion 

 after injury of the facial ; paralysis of the motor branch of the fifth being at- 

 tended by distortion of the face while the patient is at rest, and less when he 

 speaks, laughs, &c. and thus puts in action the muscles supplied by the facial 

 nerve ; paralysis of the facial being attended by distortion only when he puts 

 these in action ; and paralysis of both being attended by constant distortion and 

 an increase of it during these actions. He shows with great acuteness how 

 unsatisfactory and erroneous are many of Sir C. Bell's views and statements 

 respecting paralysis of the face. (New Views of the Process of Defecation, p. 227. 

 sqq.) Dr. Bellingeni appears to have had some vague notion of the functions 

 of the anterior part of the trigeminus and of the facial nerve ; but, since he 

 says that the facial nerve gives animal sensibility as well as motion to the muscles 

 and integuments of the face .(p. 124.), and speaks of the upper branch of the 

 trigeminus as exciting involuntary motion (p. 177. sqq.), I cannot believe that 

 he anticipated Sir C. Bell, who certainly appears to have discovered step by 

 step the office of the ganglionic portion of the trigeminum, and proved that 

 this was a double pair for sensation and motion the portion devoted to sensation 

 having a ganglionic enlargement, the other none, exactly like the spinal nerves ; 

 although its similarity in structure to the spinal nerves he candidly states to have 

 been pointed out by Prochaska half a century ago, and by Sommerring. ( The 



FF 2 



