234 
ME. GEOEGE GOEE ON FLUOEIDE OF SILYEE. 
watery vapour expelled from the brown salt itself, and 2nd, to that of the outer air ; the 
more the air was excluded the less was the percentage of loss. In each experiment some 
of the silver was set free in a coherent deposited state upon the crucible, chiefly at the 
junction with the surface of the liquid, and the crucible was slightly corroded. On dis- 
solving this silver by nitric acid, jet-black powder of platinum appeared beneath; this 
always occurs in such cases. 
A current of dried air was passed over 20 grains of argentic fluoride at a gentle red 
heat in a platinum boat within a glass tube during half an hour ; the fluoride was not 
decomposed. A current of undried air was also similarly passed over the salt in a state 
of fusion ; a little silver was set free at the ingoing end of the boat, and where the salt 
was not kept perfectly fused effervescence occurred, which caused the salt to creep up 
the sides of the boat. 
Electrolysis. 
A number of experiments were made of electrolyzing argentic fluoride in a fused state, 
with platinum electrodes and six Smee’s elements, in a covered platinum cup. In each 
case conduction commenced before the salt had fused. When the salt was liquid the 
conduction was perfect , so that on closing the circuit by a copper wire no additional 
action could be detected in the battery. No gas was evolved at the cathode, and only 
a little from the anode, most on each occasion at the first moment of conduction. The 
anode exhibited no more signs of corrosion than the cathode, nor than what always occurs 
when argentic fluoride is fused in contact with platinum. Metallic silver was set free 
in each case, but apparently only by the usual influence of moisture of the air. No film 
of coherent silver was deposited upon the cathode. I have met with similar results of 
perfect conduction without manifest electrolysis whilst passing electric currents through 
certain other metallic fluorides in a state of fusion. 
In one of these experiments, supposing that fine fibres of silver might have stretched 
across and united the electrodes, as actually does occur in some cases, I frequently 
stirred the liquid around the anode by means of a platinum wire, but no alteration of 
conduction was thereby produced, and no fibres of silver could be seen. Had such fibres 
been formed they would probably have been highly heated by the electric current and 
rendered visible. 
On electrolyzing the fused salt with an anode composed of a rod of highly ignited 
charcoal of lignum-vitse and ten Smee’s elements, only a small amount of conduction 
took place in consequence of the resistance offered by the charcoal. Gas was evolved 
from the anode, and the anode was corroded, but no special odour besides that of hydro- 
fluoric acid was perceived. According to Fremy (Chemist, New Series, vol. ii. p. 548 ; 
Comptes Hendus, April 25, 1855), who electrolyzed the fused salt in a platinum vessel, 
it decomposed easily, but the liberated silver perforated the platinum vessel in a few 
minutes. 
A special investigation is necessary to determine the amount of conduction which 
occurs without electrolysis in this and certain other fluorides in a state of fusion. 
