378 



place, the most powerful action of the battery failed to influence the 

 character of the contractions. 



In the other case, the poles having been fixed as before, and the 

 head similarly removed, powerful galvanic currents were immediately 

 transmitted. The pulsations of the heart in the opened chest at 

 once fell from thirty-five to sixteen in ten seconds, but rose again to 

 twenty on the removal of the stimulus. 



Hence it is clear that the sympathetic branches connecting the 

 cord with the cardiac ganglia have equal claims with the vagi to be 

 called "inhibitory nerves." In fact this expression seems to me 

 altogether objectionable, since there is good reason to think that the 

 same fibres which check the movements, much more commonly 

 enhance them. The only evidence afforded by my experiments that 

 the inhibiting influence is ever exerted in the natural actions of the 

 animal, consisted in the quiescence of the intestines sometimes seen 

 after a struggle, and two doubtful observations of retardation of the 

 heart's beats from the same cause. Indeed it appears very question- 

 able whether the motions of either of these viscera are, under ordi- 

 nary circumstances, ever checked by the spinal system, except for 

 very brief periods ; whereas the increased action of both heart and 

 intestines, familiarly known to result from mental emotion, may last 

 for a very considerable time. The fact that the nerves of these 

 organs are capable of setting them at rest under conditions of 

 extraordinary irritation is nevertheless a matter of great impor- 

 tance, especially in a pathological point of view, and appears to 

 afford an explanation of facts in medicine hitherto little understood, 

 such as failure of the heart's action from violent emotion or 

 pain, and the constipation which attends strangulated omental 

 hernia. 



From the observations of Spiegelberg*, it would appear that the 

 uterine contractions are promoted by mechanical irritation of the 

 cord, and arrested by transmitting a powerful stream of galvanism 

 through the spine. Also the forcible expulsion of urine very fre- 

 quently seen in the lower animals in consequence of fear, and the 

 temporary palsy of the detrusqr often witnessed in the human sub- 

 ject in surgical practice as the result of severe injury, seem to me 



* Henle and Pfeufer's Zeitschrift, 3rd series, vol. ii. part. 1. 



