Distribution of Electricity in Electrolytes. 385 
In a second experiment a silver plate, 60 x 7 millim., was 
placed within the limits of no electrochemical action, along the 
axis of a similar silver tube, but not in metallic connexion with 
it, and then placed in the electrolyte as before. The silver plate 
was completely protected from electrification, at least signs of 
both copper and peroxide were entirely absent from the sur- 
face of the plate. The electrifications on the tube itself were 
practically the same in area as in the first experiment. 
In a third experiment the plate of silver was equal in length 
to the tube, i. e. 100 millim. The electrifications on the out- 
side of the tube were again identical in area with those on the 
corresponding parts of the tube in the first experiment. The 
— on the inside was also the same, but the + measured 4 mil- 
lim. less in length. The — electrification on the plate mea- 
sured 13 millim., and the + 15 millim. 
In a fourth experiment the silver plate projected 10 millim. 
beyond the tube at both ends, i. e. the plate was 120 millim. 
long. The electrifications on the tube itself, inside and out- 
side, were practically equal in area with those in the experi- 
ment last described. The areas on the plate, however, were 
notably different. The limit of the — electrification was very 
sharply defined, and measured only 11 millim., i. e. it pene- 
trated 1 millim. only within the tube. On the other hand the 
+ measured 25 millim., and therefore penetrated 15 millim. 
within the tube, the same as in the last experiment. The 10 
millim. of the plate projecting beyond the ends of the tube 
appeared then to have exerted no appreciable influence on the 
capacity of the + electrification to diffuse itself over the sur- 
face of the plate within the tube. It was very different, how- 
ever, with the — electrification; so much so in fact as to almost 
prevent its diffusion on that part of the plate coming imme- 
diately within the shadow, so to speak, of the hollow con- 
ductor. 
Faraday's well-known experiments on the distribution of an 
electric charge on nets &c. naturally suggested the idea of 
substituting tubes of wire gauze for those of metallic silver. 
Gauze of copper wire was employed having 72 meshes to the 
square centimetre. The area of the electrifications set up on 
tubes of this material could not be ascertained with exactitude 
for the reason that the limits of the opposite electrifications 
were not so distinctly marked as in the case of the silver tubes; 
but the distribution of electrochemical action was sufficiently 
evident to leave no doubt as to the electrifications being mainly 
confined to the external surfaces of wire gauze, when in the 
form of tubes, and placed in the field of electrotytic action. 
In the annexed table is set out the length, in millimetres, 
7,7 " Mag. S. 5. Vol. 16. No. 101. Nov. Ib83. 2 E 
