Mr BAXTER, ON ORGANIC POLARITY. 



249 



while the hepatic system may, on the same view, be considered as the alkaline or negative pole. 

 He also quotes an experiment of Matteucci as, in some degree, confirming his opinion, 



Donne*, upon applying one of the electrodes of a galvanometer to the stomach and the 

 other to the liver, obtained an effect upon the needle, and the result of this experiment was 

 subsequently confirmed by Matteucci j-. 



The suggestion thus thrown out, that the stomach and liver formed poles similar to those 

 of a galvanic pile, having apparently received some confirmation from ewperimental evidence, 

 it now became of some importance to trace out the circuit, the path of the current ; and, if 

 possible, the origin of the power, so as to complete the whole evidence necessary for the proof 

 of the truth of the suggestion. 



Reasoning upon these facts, and assuming that the stomach and liver did actually form 

 the two poles similar to those of a galvanic circle, it was reasonable to suppose that the electric 

 current would pass from the stomach to the liver by the blood in the portal vein. To ascer- 

 tain the truth of this supposition I now inserted the two platinum extremities of the elec- 

 trodes of a galvanometer into the portal vein, and as far apart as possible, in order to 

 obtain the supposed diverted current ; but no effect was observed. The electrodes were then 

 inserted one into the portal vein, the other into the hepatic vein, still no effect. 



PouilletJ and Muller^, it may be observed, had previously ascertained that no effect 

 occurred when they inserted one electrode into an artery, and the other into a vein, of a living 

 animal. 



No evidence could be obtained from these experiments indicative of the path of the cur- 

 rent ; the galvanic circle was therefore not complete ; and some of the essential conditions 

 were evidently wanting. 



Repeating the experiments of Matteucci upon other animals than rabbits, the effects 

 observed by Matteucci were not always obtained ; as these results will again come under 

 consideration, they need not now detain us. 



Pondering over these failures it soon became evident that more correct notions in regard to 

 the origin of the power in the voltaic circle were requisite ; the term current also, with its 

 ordinary associations (of something flowing in one direction), was a source of great embarrassment, 

 and it was thus found that a deeper insight into a knowledge of Faraday's || opinions in respect 

 both to the origin of the power in the voltaic circle, and to that of current force in particular, 



viz, as AN AXIS OF POWER HAVING CONTRARY FORCES EXACTLY EQUAL IN AMOUNT IN 



CONTRARY DIRECTIONS, was absolutely essential. To enter upon these points, however, would 

 far exceed the limits of this paper, and it is to the admirable memoirs of this distinguished 

 individual that I must therefore refer for the requisite informationlf. 



"' Becouerel, Traiti de VElectncite, Tom. i. p. 327. 



t Ibid. Tom. iv. p. 300. 



:j: Journal de Physiologie, Tom. v. p. 6. 



5 Mulleh's Physiology, translated by Baly, Vol. i. 

 p. 148. 2nd edit. 



II Experimental Researches in Electricity. 



1 The title of the papers in the Transactions of the Royal 

 Society was so worded as to imply the notion, that these investi- 

 gations were undertaken for the purpose of applying some of the 

 discoveries of Fahaday to Physiology. To avoid this mean- 



Vol. X. Part I. 



ing a note was appended to point out in what manner the word 

 to apply was intended to be understood, viz. as shewing the ne- 

 cessity of a thorough acquaintance with Faraday's views in 

 regard to voltaic action and his definition of current force. No 

 reason has as yet occurred to lead me to alter this opinion, but 

 on the contrary ; and whatever value may be assigned to Pro- 

 fessor Grove's views, as advanced in his Essay, On the Cor- 

 relation of Physical Forces, I am still of opinion, without 

 wishing to detract from the merits of the latter philosopher 

 that the views of Faraday are by far the most philosophic. 



32 



