with Formula: for ascertaining its power. 25 1 



Hence it might be called circular chemical action, because 

 the phenomenon always evinces itself as a circle. 



These definitions suit equally every possible case, and there 

 is but one point included in those definitions which is uncer- 

 tain, though as they now stand, whichever way that doubtful 

 case be taken, they equally apply. The difficulty, and the 

 only one, that I know concerning the production of the voltaic 

 force, is an uncertainty whether the force is produced by the 

 analysis of the compound body, or the synthesis of the newly- 

 formed salt. This is a point concerning which, perhaps, we 

 shall ever be ignorant, yet analogy would rather lead us to 

 suppose that the combination rather than the analysis is the 

 source of the voltaic force. These definitions show why we 

 cannot obtain the force from the union of two elements ; in- 

 deed, we can never hope to obtain voltaic power from ordinary 

 combustion; for though the energy of the combination of oxy- 

 gen with carbon is immense, there is no second element, and 

 therefore no intermediate point at which the effects can be 

 manifested. For the same reason no force can be obtained 

 from the union of liquid sulphur or bromine with metals. 



The intensity of chemical action being always proportionate 

 to the voltaic power, and being the only source of power in 

 the pile, it follows that (I) the intensity or the power the vol- 

 taic fluid possesses of overcoming obstacles is equal to (F), 

 the affinity which regulates the chemical action. But as we 

 find that this power is lessened under different circumstances, 

 I = F — O ; O standing for the whole of the obstacles af- 

 forded to its passage. 



Let us take at once a circle and examine its properties. 

 We find that the intensity of the action (I) is equal to the 

 affinity (F) of the body used to 

 separate one element of the com- Fig. 1 . 



pound fluid (in the galvanic bat- 

 tery this is produced by the zinc 

 and oxygen) lessened by the me- 

 chanical resistances afforded by 

 the removal of the newly-formed 

 compound (a) by the obstruction 

 offered to the passage of the 

 force by the compound solution (r),by the imperfection of the 

 conducting power of the solid parts of the circuit (c), and 

 lastly, by the obstacle which is afforded to the removal of the 

 second element of the compound fluid (e) ; thus we have al- 

 gebraically I = F — a + c + r + e. This circle is supposed to 

 consist of but a single atom of fluid, exposed at one time 

 to the action of the body combining with one of its elements, 



