IN A CLOSED GALVANIC CIRCUIT. 249 



which such efflux takes place. The same law applies, without 

 doubt, to the passage of liquids through porous clay plates, 

 which represent in some measure an aggregate of very narrow 

 tubes. Similarly, however, the quantities of liquid transported 

 by a galvanic current through a clay partition, are also in direct 

 proportion to the current's intensity. If therefore the action 

 of hydrostatic pressure be equivalent to the elevation of the 

 liquid by a galvanic current of a certain intensity, then by in- 

 creasing the intensity of the current this hydrostatic pressure 

 must increase in the same proportion in order to neutralize the 

 increased action. In this manner, therefore, the transporting 

 action of a galvanic current may be represented by a hydrostatic 

 pressure. 



§9. 



By changing the magnitude of permeable surface presented 

 by the clay cylinder, it was found that the heights to which 

 the liquids ascend under the influence of the same galvanic cur- 

 rent are, under otherwise equal circumstances y inversely 

 proportional to the permeable surface presented by the clay 

 cylinder. 



The following table furnishes an example of this. In it the 



magnitude - denotes the mean ratio of the height to the cor- 

 responding intensities of current obtained in each case from 

 several experiments ; o represents the corresponding permeable 

 and conducting surfaces presented by the clay cylinder ; these 

 were gradually diminished by the application of layers of water- 

 tight and non-conducting shell-lac. 



With the whole surface 



The small deviations in the values of - o, which should all in 



I 



fact be exactly equal, may be easily accounted for by the different 



thicknesses of the clay cylinder at different places, as well as by 



SCIEN. MEM.— A^a^ Phil. Vol. I. Part III. T 



