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influence of galvanism applied to the spine, a particular part be 

 irritated, local contraction occurs, but is not propagated to neigh- 

 bouring parts. This fact is of fundamental importance, since it 

 proves that the inhibitory influence does not operate directly upon 

 the muscular tissue, but upon the nervous apparatus by which its 

 contractions are, under ordinary circumstances, elicited. 



Another point which seemed to require investigation was the well- 

 known increase of peristaltic action which takes place after death, 

 and which continues in spite of cutting off the mesentery close to 

 the gut. Those who believe in a constantly restraining function 

 of certain nerves during life might argue that the intestine has 

 always a tendency to such active movements, but is kept in check 

 by the "inhibitory nerves," and released from their control when 

 they have lost their power after death. A different explanation, first 

 suggested, I believe, by Bernard, is that the increased action of the 

 intestines is the result of failure of the circulation in the part ; and 

 to this view I felt disposed to agree, in consequence of having noticed 

 curious irregular contractions in the arteries of the frog's foot from a 

 similar cause. In order to decide the question, I tied three adjoining 

 arterial branches in the mesentery of a rabbit, thus depriving about 

 3 inches of the intestine of its circulation ; the parts so affected being 

 accurately defined by the extent of absence of pulsation in the mi- 

 nute vessels close to the gut. In about a minute and a half, vermi- 

 cular movements commenced in this part ; the rest of the intestines 

 being at the time very quiet. Powerful interrupted galvanic cur- 

 rents were then transmitted through the posterior dorsal region of 

 the spine, with the effect of causing perfect quiescence of the whole 

 of the intestine, including the part whose arteries had been tied. 

 After cessation of the galvanism the movements recurred in the por- 

 tion devoid of circulation, while elsewhere they were almost entirely 

 absent. This experiment was repeated on another occasion with 

 similar results. In one of the cases I divided the mesentery close to 

 the gut, after ligature of the vessels, but no change took place in the 

 character of the movements which had been previously induced, indi- 

 cating that the increased action in these cases had been of the same 

 nature as that which results from death. The arrest of .the move- 

 ment on the application of galvanism proved that the delicate opera- 

 tion of ligature of the mesenteric vessels had been performed without 



