356 
Proceedings of the Royal Society of Edinburgh. [Sess. 
of the room, and the modulus determined without any current, it was found 
there was an increase in its value compared with what it was before any 
current had been passed through the wire. The final effect, then, in each 
case was to produce a permanent increase in its value. 
It was also intended that brass wire should be put through the same 
course of experiments, but the temperature coefficient of resistance was so 
small that it was found impossible to determine the temperature with a 
suitable degree of accuracy. Probably it would be advisable to determine 
the temperature of brass and other alloys from the expansion of the wire. 
{Issued separately October 7 , 1907 .) 
