462 SYMPATHY. 



--..."- ' ' * 



these three discoveries he has obscured by ascribing morbid 

 phenomena dependent upon the motor branch of the trigeminus 



that the nerves arising from the respiratory tract serve not only for the sym- 

 pathetic action, as he regards it, of respiration and the expression of the passions, 

 but that they serve for the production of all sympathy and for the effects of in- 

 stinct and the passions on the system ; instinct being considered by him as a part 

 of the passions, only attended by a desire and by actions adapted to a particular 

 end, and the word passion being synonymous with emotion. The operation of 

 passion or instinct and of sympathy may be regarded as the same : the various 

 parts of the body sympathising only with the brain in the two first cases. Now 

 instinctive actions may be actions of any voluntary muscles of the body, and 

 their source must be certain parts in the brain, but the conveyance of the im- 

 pression from these parts of the brain which are the seat of the mental operation 

 must be to that other part of the brain or spinal chord whence the voluntary 

 motor nerves which excite the respective muscles arise. No peculiar system of 

 nerves is required farther for instinctive motion. Peculiar nerves or nervous fibres 

 may exist in the brain and chord, or peculiar nerves may exist only between these 

 and all parts of the body for the conveyance of the effects of the passions, and be- 

 tween the various parts of the body for their endless sympathies. Nervous commu- 

 nication there must be between all parts sympathising not through mere continuity, 

 but the communications throughout the system by means of all the encephalo-spinal 

 and ganglionic nerves are abundant enough for sympathy to occur between any 

 two. Many of the very nerves which he regards as the specific agents of sym- 

 pathy are voluntary nerves ; the facial, pathetic, phrenic, are employed by our 

 will ; and I conceive that they no more excite muscles sympathetically than any 

 other voluntary nerves, where the nerve is excited sympathetically through some 

 other nerve communicating with their roots : the fact being that these nerves of 

 motion may be stimulated at their source in the brain or spinal chord by the will, 

 or by emotion or some other excitement operating sympathetically. Dr. Fletcher 

 only makes it probable, in his own mind, that such general communications exist 

 by these peculiar nerves. He argues, 1 . That the respiratory system of nerves is 

 likely to be distributed almost universally, because the ramifications of the 

 pneumono-gastric are inextricably interwoven with the roots of the ganglionic 

 nerves, which are presumed already by him to be universally dispersed by 

 travelling with the blood-vessels, and which also reinforce every encephalo-spinal 

 nerve, so that, wherever a ganglionic nerve goes, a so called respiratory twig 

 may go likewise : this probable distribution of the pneumono-gastric nerve would 

 be sufficient to establish the universal distribution of these nerves, though others 

 of the set are probably very widely disseminated. In fish, the pneumono-gastric 

 is universally distributed. This set of nerves have almost a common origin, so 

 that by means of one's diffusion, the whole may be regarded as diffused. Thus 

 the sympathy between the lungs and the respiratory muscles is maintained by 

 the pneumono-gastric nerve distributed to the lungs and conveying the sensation 

 of want of breath ; by the phrenic and intercostals and accessory and external 

 respiratory nerves, which are associated at their roots with it, and excite the 

 muscles as well as by other muscular nerves, the pathetic, facial, and even 



