180 Dr. Faraday's Experimental Researches in Electricity, 



its natural affinity for the zinc, moves from left to right, so 

 any other body of the same class with it (?. e. any other anion), 

 and under its government for the time, will move from left to 

 right. 



963. This I may illustrate by reference to fig. 11, the 

 double circle of which may represent a complete voltaic cir- 

 cuit, the direction of its forces being determined by supposing 

 for a moment the zinc b and the platina c as representing 

 plates of those metals acting upon water, </, e, and other sub- 

 stances, but having their energy exalted so as to effect several 

 decompositions by the use of a battery at a (989.). This 

 supposition may be allowed, because the action in the battery 

 will only consist of repetitions of what would take place be- 

 tween h and c, if they really constituted but a single pair. 

 The zinc b, and the oxygen d, by their mutual affinity, tend 

 to unite ; but as the oxygen is already in association with the 

 hydrogen e, and has its inherent chemical or electric powers 

 neutralized for the time by those of the latter, the hydrogen e 

 must leave the oxygen d, and advance in the direction of the 

 arrow head, or else the zinc b cannot move in the same direc- 

 tion to unite to the oxygen d, nor the oxygen d move in the 

 contrary direction to unite to the zinc 6, the relation of the 

 similar forces of b and e, in contrary directions, to the op- 

 posite forces of d being the preventive. As the hydrogen e 

 advances, it, on coming against the platina c,f, which forms 

 a part of the circuit, communicates its electric or chemical 

 forces through it to the next electrolyte in the circuit, fused 

 chloride of lead, g, h, where the chlorine must move in con- 

 formity with the direction of the oxygen at c?, for it has to 

 compensate the forces disturbed in its part of the circuit by 

 the superior influence of those between the oxygen and zinc 

 at d, b, aided as they are by those of the battery a ; and for a 

 similar reason the lead must move in the direction pointed 

 out by the arrow head, that it may be in right relation to the 

 first 'moving body of its own class, namely, the zinc b. If 

 copper intervene in the circuit from i to k it acts as the pla- 

 tina did before ; and if another electrolyte, as the iodide of 

 tin, occur at /, m, then the iodine /, being aii anion, must 

 move in conformity with the exciting anion, namely, the oxy- 

 gen d, and the cation tin m move in correspondence with the 

 other cations b, e, and h, that the chemical forces may be in 

 equilibrium as to their direction and quantity throughout the 

 circuit. Should it so happen that the anions in their circula- 

 tion can combine with the metals at the anodes of the respec- 

 tive electrolytes, as would be the case at the platina/ and the 



