CHAP. XIII.] PACINIAN BODIES. 401 



nerves to terminate on the lamellae in the same looplike manner as 

 in striped muscle.* These lamellae are separated by fluid, and 

 only adhere through the medium of the wall of the prism. If this 

 be the true history of this structure, it appears to establish some 

 general analogy between the electrical organs and the corpuscles; 

 but how far this can be shewn to hold in essential characters, 

 especially in the mode of termination of the nerves, and their 

 arrangement with regard to the membranes and fluid, is still a 

 matter of doubt. Meanwhile we deem it most prudent to forbear 

 from speculating concerning the office of the Pacinian corpuscles. 



Having thus far completed the physiological anatomy and phy- 

 siology of nerves in general and nervous centres, we proceed 

 next to the consideration of particular nerves ; and we shall state 

 here the order in which we find it convenient to examine them. 

 The Encephalo-spinal nerves very conveniently arrange themselves 

 into the three following classes : I. The nerves of pure sense. 

 II. The nerves of motion. III. The compound nerves. The 

 first class includes some nerves, namely, the nerves of touch and 

 taste, which are mixed up with those of the third class; but, as the 

 consideration of these senses could not without great inconvenience 

 be separated from the others, we prefer to consider these particular 

 fibres along with the other nerves of pure sense, namely, the olfac- 

 tory, the optic, and the auditory. As the peculiar function of 

 those nerves depends on the peripheral organization, as well as 

 on their central connexion, their physiological anatomy involves ne- 

 cessarily that of the organs of sense. We shall commence with the 

 most simple, namely, Touch and Taste, and afterwards proceed to 

 Smell, Vision, and Hearing. 



The second class of nerves contains the third, fourth, sixth, 

 portio dura of the seventh, and the ninth pairs of nerves accor- 

 ding to Willis's arrangement, all of which are motor in function. 



In the third class we place the fifth and eighth pair of nerves, 

 and the spinal nerves. 



Lastly, we shall examine the Sympathetic nerve. 



* Comparative Anat., translated by Tulk. 



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