ELECTRICAL RESISTANCE UNDER PRESSURE. 



137 



TABLE XIX. 



"Therlo." 



4 Q .0,0 



20 40 60" 80° 

 Temperature 



100" 



5.0.232 PfplM 





^ .0,230 



3 



i .0,2 28 



d: 0' 



c 

 _o 



s 

 a 



20 40" 60° 80° 

 Temperature 



Pressure, Kg. / Cm. X 1 



Ther lo 



Figure 13. Results for the measured resistance of Therlo alloy. The 

 deviations from linearity are given as fractions of the resistance at kg. and 

 0°C. The pressure coefficient is the average coefficient between and 

 1200 kg. 



pressure. It will be noticed that the average pressure coefficient shows 

 greater variation with temperature than does that of manganin, and the 

 variations are in fact greater than the variations of resistance itself. 

 The resistance passes through a maximum in the neighborhood of 75°, 

 the increase between 0° and 75° being 0.120%, and between 0° and 

 100° 0.104%, whereas the average pressure coefficient continues to 

 increase over the entire range between 0° and 100°. The instantane- 

 ous coefficient at kg., however, passes through a maximum between 

 0° and 100°. 



" #193 Alloy." This is an alloy containing Fe 68%, Ni 30%, and 



