ON THE ELECTRICAL PROPERTIES OF PURE SULPHUR. 
149 
The net result of the measurements detailed in Table XVI. is as follows :— 
Temperature, ’14° C. 
For mixed sulphur containing 3 per cent, of insoluble sulphur . K = 3‘75 
s 3 >> 1*43 ,, ,, X = 3'51 
Completely soluble sulphur (aged monoclinic ?).K = 3'162 
The value of K for the soluble sulphur is the mean of values obtained on two 
different samples. 
It would appear from these values that the specific inductive capacity rises as the 
percentage of insoluble sulphur increases. 
Experiments have yet to be made on a cake of sulphur containing a very large 
amount of insoluble. 
The results of the experiments described in the foregoing investigation may be 
summarized as follows :— 
( 1 .) The specific resistance of perfectly soluble sulphur, either simply monoclinic, 
or aged monoclinic, i.e., monoclinic sulphur which has lost its crystallographic 
properties and become opaque, but which practically preserves its old melting-point, 
is very high, certainly above 10 28 C.G.S. units. 
( 2 .) An admixture of say 5 per cent, of amorphous sulphur reduces this great 
specific resistance to say 10 25 C.G.S. units. 
(3.) The conductivity, such as it is, is marked by some peculiarities; it tmds to 
be discontinuous, resembling in this the behaviour of surface films and of bad 
conductors (glass rods and ebonite) generally. 
(4.) The conductivity is always much greater for some time after the battery is 
reversed, say for three or four minutes. 
(5.) The “residual” charge, when the sulphur is regarded as a dielectric, is small. 
((3.) The conduction does not obey Ohm’s law. The specific conductivity is greater, 
the greater the voltage. 
(7.) The specific inductive capacity of mixed sulphur is greater than of pure 
soluble sulphur. 
( 8 .) The conductivity of mixed films increases enormously while they are annealing, 
and even perfectly crystalline sulphur shows traces of conductivity at temperatures 
near the melting-point. 
(9.) Melted sulphur conducts comparatively well, say 1000 times as well as a cold 
mixed film. 
