Bromine, Iodine, and Chlorine for Electricity. 133 
iodide of potassium indicated that the current was passing; 
but the liquids in the tube G were not visibly affected. 
11. An aqueous solution of the periodide of bromine being 
put into the tube G, conducted, and was briskly decomposed ; 
but both the platinum wires remained bright and clean, and 
neither iodine, bromine, nor any compound of them, was 
evolved or deposited on either electrode, though the action 
was continued for some time. 
12. A solution of the periodide of bromine was a good con- 
ductor, and the current transmitted had sufficient intensity for 
the electrolyzation of water. Solutions of the periodide, in 
chloride of sulphur and carburet of sulphur, were nonconduc- 
tors; upon the addition, however, of a few drops of zther, they 
became good conductors. 
13. The conducting power of chlorine was next tried, and 
for this purpose the following apparatus was employed: A BC, 
Fig. 2. 
fig. 2, is a glass tube ;*,ths of an inch in diameter, having two 
platinum wires fused into it at A, so as to be separated the 1,th 
of an inch from each other ; the tube being then inverted, the 
space from E to F was filled with peroxide of manganese and 
muriatic acid; the end C was then carefully closed by a spirit 
lamp, and the whole being cooled, it was placed in the posi- 
tion represented in the figure, the space from E to C being 
filled with a mixture for generating the chlorine, the other 
parts of the tube having been carefully kept dry. Heat was 
then applied to C, and B was immersed in ice-cold water; as 
soon as a sufficient quantity of liquid had collected in B, A 
was immersed in a mixture of ice and salt, and B was gently 
warmed ; by this means the liquid chlorine was rectified, and 
obtained quite free from water or other extraneous fluids at A. 
Matters being thus arranged, and sufficient chlorine having 
been condensed, the tube was placed in the same position as 
the tube G in the former figure, one of the two platinum wires 
resting on the moistened paper F, the other upon E, fig. 1. 
I was at first surprised by finding it a conductor; but when 
the tube was carefully wiped, so as to be quite free from all 
adhering salt from the freezing mixture, it proved a perfect 
nonconductor. 
