chemical Agencies of Electricity. 29 
trariwise, that oxygene and acid substances are attracted by 
positively electrified metallic surfaces, and repelled by nega- 
tively electrified metallic surfaces ; and these attractive and re- 
pulsive forces are sufficiently energetic to destroy or suspend 
the usual operation of elective affinity. 
It is very natural to suppose, that the repellent and attrac- 
tive energies are communicated from one particle to another 
particle of the same kind, so as to establish a conducting chain 
in the fluid ; and that the locomotion takes place in conse- 
quence ; and that this is really the case seems to be shown by 
many facts. Thus, in all the instances in which I exa- 
mined alkaline solutions through which acids had been trans- 
mitted, I always found acid in them whenever any acid matter 
remained at the original source. In time, by the attractive 
power of the positive surface, the decomposition and transfer 
undoubtedly become complete ; but this does not affect the 
conclusion. 
In the cases of the separation of the constituents of water, 
and of solutions of neutral salts forming the whole of the 
chain, there may possibly be a succession of decompositions 
and recompositions throughout the fluid. And this idea is 
strengthened by the experiments on the attempt to pass ba- 
rytes through sulphuric acid, and muriatic acid through solu- 
tion of sulphate of silver, in which, as insoluble compounds 
are formed and carried out of the sphere of the electrical 
action, the power of transfer is destroyed. A similar con- 
clusion might likewise be drawn from many other instances. 
Magnesia and the metallic oxides, as I have already men- 
tioned, will pass along moist amianthus from the positive to the 
negative surface ; but if a vessel of pure water be interposed, • 
they do not reach the negative vessel, but sink to the bottom. 
