256 NERVOUS SYSTEM. 



comes pale and flaccid, and stomach-digestion is arrested. 

 Afterward, very feeble movements of the stomach may oc- 

 cur as the result of local irritation, and small quantities of 

 food, very finely divided, may be digested. Galvanization 

 of the nerves in the neck produces contractions of the mus- 

 cular coats of the stomach. This action probably takes place 

 through sympathetic filaments going to the pneumogastrics 

 high up in the cervical region. Section of the nerves slight- 

 ly retards absorption from the stomach. 



After division of both pneumogastrics in the neck, purga- 

 tive poisons, given even in fatal doses, generally fail to pro- 

 duce watery discharges from the intestine. 1 



1 Compression of the pneumogastrics has lately been recommended by Wal- 

 ler to produce anaesthesia in surgical operations, etc. The effects of pressure 

 of these nerves in the human subject are described by Aristotle, quoted by 

 Waller. In some cases, the patient falls instantly, as if struck by lightning, 

 while in others the effects are not so marked. Waller has employed this method 

 for the production of anaesthesia under varied conditions, and has never ob- 

 served any serious after-effects. He relates a case of successful reduction of a 

 very difficult dislocation of the shoulder, which had resisted previous efforts, 

 after two or three minutes of simultaneous compression and traction. He also 

 relates a case of painless extraction of a tooth by the same means. The im- 

 possibility of compressing the pneumogastrics, in the human subject, without 

 disturbing the circulation in the brain by pressure on the carotids, in view of 

 the fact that cerebral anaemia produces anaesthesia, renders it impossible to ac- 

 cept, without reserve, the conclusions of Waller. (WALLER, On the Compression 

 of the Vagus Nerve, considered as a Means of producing Asthenia or Ancesthesia 

 in Surgical Operations, Practitioner, London, December, 1870, No. xxx., p. 

 822.) 



