550 M. PoggendorfF on certain GaJmnic Circuits* 
the hypothesis imagined by De la Rive to get rid of the same 
difficulty^ viz., that the electricities separated by the chemical 
process find a partial reunion at the very place where they are 
developed, and consequently the intensity of the current need 
not necessarily stand in direct proportion to the energy of this 
process, — an hypothesis which has already been dissected by 
Fechner*, and, in my opinion, founders even upon this ground 
alone, that, cmteris paribus^ the current is the more intense the 
better the fluid conducts, L e. the easier this reunion can take 
place in it. 
It is certainly an advantage of the contact-theory that it needs 
neither the one nor the other hypothesis, but is perfectly satis- 
fied with the simple view, that the so-called local action, that 
which happens even previously to the closing of the circuit, is 
a pure chemical process not at all appertaining to the circuit : 
but the advantage were but slight, if it could merely enumerate 
in its favour the simplicity of this view ; its real superiority over 
the chemical theories it acquires from its being a view well 
founded on facts. All cases more accurately examined, whether 
it be in the present Memoir or in previous ones by Fechnerf 
and others, prove in the most evident manner that the energy 
of the direct chemical attack of the fluid on the positive metal 
does in no way stand in any connexion with the intensity of the 
excited electromotive force. And on the other hand it is not 
proved that the local action is ever converted into circulating, or 
weakened by it J. What has been advanced as such, is evidently 
founded on error. The decrease of the hydrogen at the zinc 
which results on the closing of the circuit, does not happen 
from a transfer of this hydrogen to the negative metal, but 
simply from the oxygen being carried by the current to the 
zinc, and there combining with the hydrogen. I hope shortly 
to be able to confirm this by facts. 
The following note has been communicated by M. Poggen- 
dorfF to the Translator, with a request that it should be added : 
As I did not foresee on penning this memoir that it would have the honour of 
being translated into English, it may he necessary to observe that I had not the 
intention of bringing forward a complete refutation of the chemical theory of 
galvanism, but merely to show that two facts recently brought forward in favour 
of this theory do not prove what it is intended they should. For the same rea- 
son many things have been passed over, or but briefly noticed, which appeared 
unnecessary for Germany, but which needed a more detailed exposition for the 
English readers, who in general are unacquainted with the researches of Ohm 
and Fechner. Among others, might here be enumerated the distinction between 
electromotive force and intensity of current, the not taking which into considera- 
* PoggendorfF’s Annalen, vol. xlv. p. 232. 
f For instance, PoggendorfF’s Annalen, vol. xliii. p. 433. 
X Exp. Researches, § 996. 
