236 Influence of Occluded Gases on Thermo-electricity. [May 31, 



Temperature. 



Specific heat. 



-50-3° 



.. 0-1138, 



Graphite -10 '7 



.. 0-1437 



61 -3 



... 0-1990 ! 



0'2542| 

 . . -2966| 



138 -5 



201 -6 



249 -3 



. . -3250j 

 . . -4454| 

 . . -4539 ! 

 0-467 ' 



641 -9 



822 



977 



Eate of change per 1° C. 



0-00075 



A 



u 



UUU/D 







•00071 







•00067 







•00063 







•00030 







•000045 







•000083 



The carve, fig. 9, is plotted from these numbers and shows a fairly 

 regular increase in the specific heat with the temperature up to 250° 

 where the line bends ; another bend occurs at 650°. 



Other changes were looked for at the higher temperature, but the 

 contacts gave way, and no definite results were obtained. In con- 

 clusion I wish to acknowledge my obligations to Professor J. J. 

 Thomson, F.R.S. and to R. T. Glazebrook, F.R.S., for much informa- 

 tion and advice during the whole course of the work. 



Summary of Results. 



A. Effect of contact of 



hot and cold car- 

 bon. 



B. Thermo-electric line 



C. Rate of decrease of 



resistance per de- 

 gree per ohm. 



D. The rate of increase 



of the coefficient 

 of expansion. 



E. Rate of increase of 



the specific heat. 



Below 250° C. 

 Current from 

 cold to hot. 



Rises. 



Diminishes. 



Increases. 



Above 250° C. 

 Current from 

 hot to cold. 



Falls. 

 Increases. 



Decreases. 



Fairly regular. Falls to half. 



