on Electric Currents m Warm-blooded Animals. 273 



whilst into another part of the same animal is plunged {en- 

 fonce) another stylet formed like the preceding one, and like 

 it furnished with an insulating handle. It is understood that 

 by means of the interposition of the animal, the circuit of the 

 galvanometer is thus complete. 



At the moment when the two stylets are plunged {enfonce) 

 into the two parts of the animal, there is disengaged from the 

 torrent of animal life, by the effect of a vital reaction, an elec- 

 tric current, which, diverted from its natural conductors by the 

 presence of the metallic body which is plunged into the or- 

 ganic substance, directs itself along the stylets and the wire 

 conductors which are soldered to them, so as to complete the 

 circuit by the same wires and in the animal parts which are 

 interposed: thus in this circuit the current having'to pass 

 over the multiplicator of the galvanometer, the deviations 

 which take place in the magnetic needle of this instrument 

 indicate its intensity and direction. 



This is the explanation which the authors have thought 

 proper to give as well of the operation as of the very simple 

 apparatus which serves for it. This, however, is not all which 

 should concur to ensure the result of the experiments ; there 

 are still some circumstances which exert a great influence 

 upon it, such as the perfection of the galvanometer, the na- 

 ture of the metal of which the instruments are made, the ho- 

 mogeneity of the stylets, every intervention of chemical sub- 

 stances, the nature of the season, the state of the atmosphere, 

 the painful preparations of the animal, its organic develop- 

 ment as well as its age, and lastly, its greater or less degree of 

 sensibility, &c. ; conditions which might appear too nume- 

 rous to allow us to hope anything from similar researches, if 

 the results already obtained did not show the contrary. 



The authors, considering the existence of electric cur- 

 rents in warm-blooded animals as sufficiently proved, ask if 

 they should call them vital, and supposing that this name 

 should be given them, what should be understood by vital 

 current't They adopt the whole definition which MM. Puci- 

 nolti and Pacinotti have given of it, and which I quoted above; 

 they also adopt for the time being the denomination o^ electro- 

 vital cuirent. 



Besides this electro-vital current, they have verified in the 

 same animals two other currents which had been mentioned 

 by the Professors of Pisa ; the one is the common electro-chemi- 

 cal current ; the second the thermo-electric. The first is di- 

 vided into the common electro-chemical current^ properly so 

 called, and the vital electro-chemical current; this is the cur- 

 rent which is supposed to proceed from the intimate chemism 



Phil. Mag. 8. 3. Vol. ly. No. 117. Al^ril 184-1. T 



