Sm THIRD REPORT— 1883. 



the electrical current, and that it is due to a force either super- 

 added to, or giving direction to, the ordinary chemical affinity 

 of the bodies present. The decomposing body may be consi- 

 dered as a mass of acting particles, all those which are included 

 in the course of the electrical current contributing to the final 

 effect : and it is because the ordinary chemical affinity is re- 

 lieved, weakened, or partly neutralized by the influence of the 

 electric current in one direction parallel to the course of the 

 latter, and strengthened or added to in the opposite direction, 

 that the combining particles have a tendency to pass in oppo- 

 site courses. 



In this view the effect is considered as essentially dependent 

 upon the mutual chemical affinity of the particles of opposite 

 kinds. A particle could not travel from the negative towards 

 the positive pole unless it found other particles in its course 

 inclined to travel from the positive to the negative pole. As far 

 as regards two compound particles, the case may be considered 

 as analogous to one of ordinary chemical decomposition ; but 

 as all the compound particles in the course of the electric cur- 

 rent, except those actually in contact with the poles, act con- 

 jointly, the case becomes more complicated, though not more 

 difficult of comprehension. 



Many facts were then quoted in illustration of the manner in 

 which particles acting under the force of their ordinary che- 

 mical affinities, governed in a greater or smaller degree for the 

 time by the passing current, according to its force or quantity, 

 would render themselves, or be excluded at the opposite extre- 

 mities of the decomposable mass in the direction of the currents. 

 Dilute sulphuric acid of a certain strength was found, when sub- 

 mitted to the action of the pile, to yield after a time a stronger 

 acid at the positive than at the negative side ; i. e. a certain 

 quantity of acid had been transferred from the negative towards 

 the positive pole : but when the acid was previously neutralized 

 by an alkali, then a far greater quantity of acid was transferred 

 by the same current of electricity. These and many other ex- 

 perimental results will appear in the fifth series of Experimental 

 Researches, to be published in the Philosophical Transactions. 



All the phagnomena of transfer of acids through alkalies, &c. 

 &c., which appeared so extraordinary to Davy and others when 

 they were discovered, are the necessary consequence of the 

 theory of Mr. Faraday ; and, in fact, such transferences are by 

 him considered as essential to electro-chemical decomposition. 



The manner in which the evolved elements are set free at the 

 poles, inexplicable upon the old theories, are necessary conse- 

 quences of his theory ; or if they combine, still the effects are 



