Strain on the ThermO'electric Qualities of Metals. 167 



pleted, and readings taken when there was 5' C. further rise of 

 temperature, and so on up to a difference of about 100° C, the greatest 

 difference tried in these experiments. A curve was plotted with 



Fig. 1. 



differences of temperature between the hot and the cold junction as 

 abscissae, and currents through the galvanometer as ordinates. The 

 mean current per degree difference of temperatiu*e as found from each 

 ciu*ve is given in Table 1. 



Table 1. 



Conductor. 



Condition of conductor. 



Current from 1 to 2 

 through, the hot- junction. 



Current in mikro- 

 ampere per degree 

 up to 100'' C. 







1 -0567 

 1 0-0065 

 1 0-213 

 1 -0124 

 1 -0036 







§ 4. The steel wire was annealed by coiling it roimd a large cast-iron 

 ball, which was heated in a bright coal fire for about an hoiu". After 

 being taken out of the fire, the ball, with the iron wire round it, was 



P 2 



