258 PROCEEDINGS OF SECTION A, 
was raised above 100°. While the annealing process was going on 
there was an immense increase of conductivity. This might be due 
either to the fact that the annealing was going on, or else merely to 
the fact of the sulphur being at the high temperature in question. 
In order to determine between these alternatives the cell was 
again heated in the same manner as before and the galvanometer 
kicks noticed. 
At the temperature of the room no deflection at all could be 
detected, the sulphur being probably almost completely soluble. 
On heating, none of the former changes of conductivity could 
be noticed. At 57:°5° C. the kick, or reversal, was 2 divisions, 
and the reading the same very nearly all the time the cell was 
being heated up to 110°, and after it started to cool again. The 
elongations varied slightly between 1 and 3; but on account of the 
smallness of the deflections, and the small movements of zero, the 
variations may have been due to errors of reading as much as to 
variation of the properties of the sulphur. They may also have been 
caused by the intermittent conductionfrequently shown by sulphur, 
No series of changes was gone through on this second heating 
such as upon the first heating, showing that the great increase of 
conductivity above 100° at the first heating was not due to the 
temperature alone, but was due either to the fact that the process 
of annealing and the change from insoluble to soluble sulphur 
was actively going on, or to the fact that insoluble sulphur pos- 
sesses the power of conduction when mixed with the soluble 
variety. The experiment, as a test of whether the progress of the 
change from insoluble to soluble was the real cause of the con- 
ductivity, remains indecisive. 
After again cooling, no current whatever could be detected 
through the sulphur. 
On testing its solubility, it was found that there was only a 
trace of insoluble sulphur present. 
An analysis of a piece of sulphur broken from the cell previous 
to annealing gave as the composition 19°68 per cent. of insoluble 
sulphur. Of the cells made by the first method two were analysed, 
giving as their composition 15:69 and 21:35 per cent of insoluble. 
Though the sulphur was considerably cracked after the first 
annealing, it is probable that the separation of the sulphur from 
the wires was not sufficient to account for the total change of 
conductivity. 
No. 9.—RESULTS FROM VARIOUS-SIZED RATIN- 
GAUGES. 
By H. C. Kippiz, F.R.MLS. 
(Read January 11, 1898.) 
