THERMO-ELECTRIC QUALITY UNDER PRESSURE. 



331 



Cohah. This was from the same length as the resistance specimen, 

 but was not the identical piece. Part of this wire had not been previ- 

 ously annealed, and it was therefore annealed before these runs 

 exactly as was the resistance piece. Five strands in parallel were 



'0° 10° 20° 30° 40° 50° 60° 70° 80° 90° 100° 



Temperahire 

 Cobalt 



Figure 25. Cobalt. Thermal E.M.F. of a couple composed of one branch 

 of uncompressed metal, the other compressed to the pressure in kg./cm.^ 

 indicated on the curves, the junctions being at 0°C and the temperature 

 plotted as abscissae. 



used, insulated as usual with short pieces of glass. The wire is more 

 inhomogeneous than most of the other metals, as was shown by the 

 rather large permanent zero effect, which was two or three times 

 larger than the total pressure effect. However, the permanent zero 

 remained so constant that fairly good measurements could be obtained. 



