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of the galvanism the previous intestinal motion returned. The rods 

 were then removed from the helix, and the battery, thus diminished, 

 was applied on several occasions, with markedly increased action of 

 the intestines in every instance during the first twenty-five minutes. 

 In the next half hour the increase of action from the galvanism, though 

 still distinct, was less strongly marked ; and at the end of that 

 period, the rods having been reintroduced, the inhibiting influence 

 was also found to be much less complete than before, indicating 

 that the parts of the nervous apparatus concerned were in a less 

 active condition, no doubt in consequence of exhaustion. The arches 

 of the tenth and eleventh dorsal vertebrae having been removed be- 

 fore the experiments with galvanism, I subsequently introduced a 

 fine needle into the exposed part of the cord, with the effect of 

 causing in repeated instances increased movements of the intestines, 

 which were especially striking on account of the occurrence of pecu- 

 liar local contractions not seen at other times. Further observations 

 upon this animal tended to confirm those which have been men- 

 tioned, as did an experiment of the same kind performed the next 

 day upon another rabbit. 



I afterwards found that the best mode of proceeding was to re- 

 move the skin and one or two layers of muscles from a portion of 

 the abdomen till the parietes were sufficiently thinned to permit the 

 intestines to be distinctly seen through them; by this means the 

 complication produced by exposure of the intestines to the atmo- 

 sphere was avoided, and the most satisfactory results were obtained ; 

 the increase of the peristaltic movements during the transmission of 

 extremely feeble shocks being strikingly apparent and constant on 

 every occasion. During the experiment performed in this way I 

 noticed several times that a violent struggle on the part of the rabbit, 

 when the intestines were in pretty free movement, was followed by 

 absolute and universal quiescence of those organs for several se- 

 conds ; this appeared to me of great interest, as proving that the 

 inhibitory influence is certainly sometimes exerted in the natural 

 actions of the animal, and is not merely the result of artificial sti- 

 mulation. 



In the course of the above experiments several other observations 

 were made. In the first place I verified the statement of Pfliiger, 

 that if, when the intestine is lying relaxed under the inhibiting 



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