Electricity and Galvanism, 247 



results of the doctor's researches on the effects of division of the 

 pneumogastric nerves arresting the digestive process : the effects of 

 the electric current in developing this function after division of the 

 nerves is however variously reported. Now, most certainly, these 

 discrepancies cannot be admitted as furnishing anything valid against 

 Dr. Philip's views, unless, in addition to the use of the battery, the 

 direction of the current was distinctly indicated, for unless the posi- 

 tive current entered the stomach it would not cause the separation of 

 free acid ; as, if the negative fluid entered, free alkali would alone be 

 developed. 



There is, in connection with this hypothesis, a most interesting 

 and important observation of Professor Matteucci, to whose ingenu- 

 ity and patience we are so largely indebted : this philosopher intro- 

 duced a plate of platinum into the stomach of a living rabbit, placed 

 another on the liver, and connected both with a galvanometer ; the 

 needles instantly traversed an arc of 20°, proving the existence of a 

 powerful current between the liver and stomach. This, it may be 

 observed, shows the existence of a current, but does not prove 

 whether it is to be regarded as an effect or a cause of the chemical 

 changes alluded to, for it has been already shown, that when an acid 

 and alkaline fluid are separated by permeable structures, they actual- 

 ly develope a current of electricity ; and as the stomach contains an 

 acid, and the liver an alkaline secretion, this might afford an expla- 

 nation of the current observed by Matteucci ; and had the experiment 

 ended here, this plausible objection would have been a fatal one. But 

 the nerves and vessels passing into the abdomen were divided above 

 the diaphragm, and in an instant the needles of the galvanometer 

 deviated to 3° instead of 20° ; and on cutting off the head of the 

 rabbit by a sudden blow, even this little deviation nearly completely 

 vanished. Nothing could be more conclusive than this experiment 

 in proving that the electric current was the cause, not the effect, of 

 the chemical metamorphosis of the saline ingesta, whose decomposi- 

 tion furnished acid to the stomach and alkali to the liver. How this 

 current is excited is unknown, although it can hardly be doubted 

 that one of the causes which we have already examined is competent 

 for this purpose ; but then there remains the difficulty of pointing 

 out the route taken by the current to reach respectively the liver and 



