1824.] Analyses of Books. 227 



Article XIV. 



Analyses of Books. 



Philosophical Transactions of the Royal Society of London, for 



1823. Part II. 



(Continued from p. 147.) 



XXI. Second Part of the paper on the Nerves of the Orbit. By- 

 Charles Bell, Esq. Communicated by Sir Humphry Davy, Bart. 

 Pres. RS. 



The following extract from the concluding pages of this paper, 

 gives the general results of Mr. Bell's investigation of the nerves 

 of the head. 



" I hope I have now unravelled the intricacy of the nerves of 

 the head, and have correctly assigned to each nerve its proper 

 office. In our books of Anatomy, the nerves are numbered 

 according to the method of Willis, an arrangement which was 

 made in ignorance of the distinct functions of the nerves, and 

 merely in correspondence with the order of succession in which 

 they appear on dissection. 



" The first nerve is provided with a sensibility to effluvia, 

 and is properly called olfactory nerve. 



" The second is the optic nerve, and all impressions upon it 

 excite only sensations of light. 



" The third nerve goes to the muscles of the eye solely, and 

 is a voluntary nerve by which the eye is directed to objects. 



" The fourth nerve performs the insensible traversing motions 

 of the eyeball. It combines the motions of the eyeball and 

 eyelids, and connects the eye with the respiratory system. 



" The fifth is the universal nerve of sensation to the head and 

 face, to the skin, to the surfaces of the eye, the cavities of the 

 nose, the mouth and tongue.* 



" The sixth nerve is a muscular and voluntary nerve of the 



e y e - 



" The seventh is the auditory nerve, and the division of it, 

 called portio dura, is the motor nerve of the face and eyelids, 

 and the respiratory nerve, and that on which the expression of 

 the face depends. 



* " In this view of the fifth nerve, I have not touched upon its resemblance to the 

 spinal nerves. But if we had ascended from the consideration of the spinal nerves to 

 the nerves of the head, we should then have seen that the fifth was the spinal nerve of 

 the head ; that it had a ganglion at its root, a double origin, and from its power over 

 the muscles of the jaws and mastication, that it was a double nerve in function, being 

 that nerve which bestows sensibility, at the same time that it sends branches to the 

 original muscles ; that is to say, to that class of muscles which are common to animals 

 in every gradation. In all these respects it resembles the spinal nerve*." 



q2 



