SYMPATHY. 459 



depend upon a primitive difference of inner structure, and be 

 essentially necessary for difference of structure : whence Baron 

 Cuvier naturally concluded that * nerves are not all entirely alike, 

 and do not all convey one fluid, like the arteries, for example ; 

 but that there are in the structure and mode of action of each, 

 some peculiarity relative to the functions and nature of the organ 

 which they animate.' I should say not animate, but influence." 11 



Sir C. Bell teaches that certain nerves are destined for Respir- 

 ation and the Expression of the passions. These he terms re- 

 spiratory nerves ; and says they are the pathetic or internal motor 

 of the eye, the portio dura of the seventh or facial, the glosso- 

 pharyngeal, the eighth or pneumono-gastric, the accessory, the 

 phrenic, and the long subclavicular or, as he terms it, external 

 respiratory. These all arise, he says, in a tract, by him called 

 respiratory, beginning at the mesocephalon, and descending on 

 each side between the anterior or motor, and the posterior or 

 sensitive, portion of the spinal chord, and terminating about the 

 middle of the back. Chaussier " had previously pointed out the 

 lateral tract, as suggested by Le Gallois *, especially the portion 

 contained in the skull, and suspected respiration to depend much 

 upon it. 



It is undoubted that several of these nerves are concerned in 

 respiration and actions in which respiration is affected, in sneez- 

 ing, coughing, &c., as well as in the expression of the passions, 

 in laughing, crying, and the expression of rage, terror, &c. But 

 why the nerves of voluntary motion which are concerned in these 

 actions should be regarded as different from other nerves of vo- 

 luntary motion, I cannot imagine. Respiration is accomplished 

 by muscles as voluntary as any voluntary muscles, and moved by 

 nerves as voluntary as any other nerves of voluntary motion. 

 We inspire because prompted to do so by uneasy sensation, just 

 as we move from an uneasy posture. The pathetic, facial, ac- 

 cessory, phrenic, and long subclavicular, differ in no point from 

 other nerves of motion ; by their means we contract at pleasure 

 the muscles to which they are distributed : in truth, the superior 

 oblique muscle of the eye supplied by the pathetic, and some, as 

 the orbicularis palpebrarum, supplied by the facial, have no con- 



r Gall, 1. c. 4to. vol. i. p. 128. sq., and 8vo. t. vi. p. 312, sq., where he quotes 

 this part of the first 4to. volume under the name of Mon Traite sur la Difference 

 des Nerves. 



8 Exp. Sommaire,$c. 1807. * Sur le Principe de la Vie, 1812. 



