440 NERVOUS SYSTEM. 



tion and sensation in the leg of that side, but the tempera- 

 ture of the two sides remained the same. He afterward ex- 

 posed and divided the sciatic nerve on that side, and then 

 noted a decided increase of temperature. 1 This experiment, 

 which is only one of a large number, shows conclusively that 

 the ordinary mixed nerves contain vaso-motor fibres, which 

 are entirely independent of the nerves of motion and sensa- 

 tion, a fact which is admitted by all physiologists, and has 

 frequently been illustrated in cases of disease in the human 

 subject. 



It only remains to show that the phenomena following 

 section of the sympathetic in animals are illustrated in cer- 

 tain cases of disease or injury in the human subject. It is 

 excessively rare to observe traumatic injury confined to the 

 sympathetic in the neck. A single case, however, apparently 

 of this kind, has lately been reported by Mitchell. A man 

 received a gunshot-wound in the neck. Among the phe- 

 nomena observed a few weeks after, were, contraction of 

 the pupil on the side of the injury, and, after exercise, flush- 

 ing of the face upon that side. There was no difference in 

 the temperature upon the two sides, during repose, but no 

 thermometric observations were made when half of the face 

 was flushed by exercise. 2 Dr. Bartholow has reported sev- 

 eral cases of unilateral sweating of the head, two observed 

 by himself, in several of which there was probably compres- 

 sion of the sympathetic from aneurism. In those cases in 

 which the condition of the' eye was observed, the pupil was 

 found contracted in some and dilated in others. In none 

 of these cases, were there any accurate thermometric obser- 

 vations. 3 In a series of observations by "Wagner, upon the 

 head of a woman, eighteen minutes after decapitation, pow- 



1 BERNARD, RecJierches experimentales sur les nerfs vasculaires et calorifiques 

 iu Tjrand sympathtque. Journal de la physiologic, Paris, 1862, tome v., p. 389. 



8 MITCHELL, Injuries of Nerves, Philadelphia, 1872, p. 318. 



3 BARTHOLOW, Unilateral Sweating of the Head. Quarterly Journal of Psycho- 

 logical Medicine, New York, 1869, vol. Hi., p. 134, et seq. 



