of Electrical and Chemical Changes. 1 93 



actually found to be correct; six arcs of platinum in vessels 

 filled with solution of nitre, were connected with a voltaic 

 battery of 50 pairs of plates: of course each arc gave off" 

 oxA'gen, and collected acid round the pole in the })lace of the 

 zinc, and afforded hydrogen and collected alkali round the 

 pole in the place of the noble metal : on separating the six 

 arcs from the battery, they were found to possess independent 

 action, the poles which were negative being positive, and those 

 positive being negative : in short, the combination acted as if 

 an original one, consisting of acid, alkali, and platinum. 



With arcs of zinc, the results were of the same kind, but 

 the electrical effects were much more distinct : as the tarnished 

 zinc in this case added its own negative power to that pro- 

 duced by the contact with the acid. 



In trying similar experiments with six arcs of tin, silver, 

 copper, and other metals, and using different saline solutions, 

 it was found that the reversed electrical effects were most 

 powerful with the most oxidable metals, and the most con- 

 centrated and most decomposable solutions ; and the weakest 

 arrangement of this kind was with arcs of platinum and pure 

 water; yet even in this instance the water had become slightly 

 alkaline at one pole, and acid at the other. 



These experiments, showing the nature of the chemical 

 changes in combinations made active by their connexion with 

 voltaic batteries, and the influence of the newly developed 

 chemical agents, fully explain the phaenomena of the secondary 

 piles of M. Ritter ; and combined with the fact, that the me- 

 tals are not perfect conductors for electricities of very low in- 

 tensity, they offer a simple and adequate solution of the cir- 

 cumstances observed by M. De La Rive on the interposition 

 of different metallic plates in the fluids connecting together 

 voltaic combinations*. 



From the nature of the chemical changes taking place in 

 each single circle of a common voltaic battery, it is evident, 

 that if any small part of a battery for some time in action, is 

 separated from the whole, and made to act as a distinct com- 

 bination, its powers must be feebler than if it had been ori- 

 ginally an independent series; for the electrical action occa- 

 sioned by the cliemical agents developed in it, are such as to 

 counteract the effects produced by the contact of the metals. 

 Whereas, it a small voltaic series is connected with a much 

 larger one, in reverse order, its oxidable in the place of the 

 noble metals, though the whole power of the combination is 

 much weakened by it when in union; yet, when separated, 



• Aiinitict (Ic Cldmic ti de Pht/sique, torn, xxviii. p. 190. 

 New Series. Vol. 1. No. 3. March 1827. '-^ C it 



