38 OUERENT FOECE CHAP. IV. §. II. 



the abdomen; one electrode was coated with bile, 

 and then both of the electrodes were dipped into 

 the blood in the chest. It was generally found that 

 the electrode in contact with the blood was positive, 

 but not always ; sometimes vibrations of the needle 

 only occurred, at other times the needle went as far 

 as 80° or 90°, and then stopped. The motions of 

 the needle presented quite a different character to 

 those observed when the bile in the gall-bladder 

 and the blood flowing from the vena cava inferior 

 were formed into a circuit; the latter presented a 

 steady character, they could be depended upon; 

 whereas with the former a greater effect might be 

 produced at first, and it would then cease, or perhaps 

 go in the opposite direction. The following con- 

 clusion may therefore be deduced : when the electrodes 

 of a galvanometer are brought into contact, one with the 

 bile in the gall-bladder, and the other with the blood in 

 the hepatic vein, or vena cava ascendens, an effect occurs 

 upon the needle, indicating the secreted product (the biU) 

 and the blood to be in opposite electric states. 



It may be said, and with apparent justice, that if 

 the actions which occur during secretion be similar 

 to those that take place in the exciting cell of a 

 voltaic battery, as was suggested in the previous 

 Section, the electrode in contact with the alkaline 

 bile ought now to indicate a positive state. 



The force of this objection depends entirely upon 

 the assumption that the bile contains a free alkali. 

 The researches of chemists, and especially Liebig, 



