OF CURRENT FORCE DURING SECRETION. 
249 
E A inserted into the centre of the mass of food in the stomach, E B lightly 
pressed on the upper external surface over E A ; E B slightly positive : E B placed 
on the liver or intestines ; E A slightly positive. 
E B and the broken plate of E C were placed, one on the upper surface of the 
stomach, the other on the mesentery ; no effect. Some food was taken out of the 
stomach and placed on the intestines, the broken plate on the mesentery, EB on the 
food ; E B positive. The same arrangement was made with some of the contents of 
the caput coli ; the latter slightly positive. 
The following circuits were formed : food from the stomach and contents of the 
caput coli ; the former positive : some food from the centre of the mass in the stomach, 
and some in contact with the mucous surface; the latter positive. The mass in the 
stomach was coarse, dry and compact ; that in the caput coli of a finer and softer 
consistence. 
The parts were covered over with a towel for twelve hours. 
E B placed on the upper external surface of the stomach, E A inserted into the caput 
coli ; E B positive. E A remaining, E B on the small intestines ; effect very slight. 
E C inserted into the centre of the contents of the stomach, E B lightly pressed 
on the upper external surface ; E C positive. The stomach was moved over and E B 
placed on that which had been its inferior surface ; E B positive : E B was placed on 
the part where the stomach had been lying ; E B positive. 
The different parts had become more moist. 
No doubt can exist as to the cause of the production of the effects obtained in the 
last experiment, viz. the difference of the fluids and solids in contact with the elec- 
trodes. The proposition, that, when two heterogeneous fluids are separated from 
each other by a membrane, or any other porous diaphragm, that which performs the 
part of an acid takes positive electricity, the other, that of an alkali, takes negative 
electricity, has been well established by Becquerel*. The results observed in the 
last experiment beautifully illustrate it ; and at the same time show how impossible 
it is to say, a ■priori, what would be the effect upon the needle when the electrodes 
are inserted into different parts of a dead animal. The mere circumstance of placing 
the electrodes in contact with different portions of the contents of the stomach pro- 
duces an effect or not upon the needle ; the state of the parts as to moisture, and the 
transudation of the secreted fluids or contents through the walls of the different 
viscera ; the contents of the colon and of the stomach considered as a mass, forming 
one conducting body ; the difference with respect to the extent of surface of the 
electrodes; each of these circumstances maybe readily seen to be influential and 
unnecessary to particularize. There may be two or three acting points between the 
electrodes, determining the current in opposite directions, or assisting each other, 
the action upon the needle being the result of a differential, or of a combined current, 
according to circumstances. 
Shall we be justified in referring the effects observed in experiments 2, 3, 4, 6, 7 
* Traite de I’Electricite, tom. iii. p. 387. v. part. ii. p. 192. 
