620 



BRinOMAX. 



TABLE XVIII. 

 Tungsten. 



Electric Co., but his sample was obtained in 1910. There would seem 

 to be no reason to suspect the purity of his sample to be greater than 

 mine. Dr. Coolidge says that the impurity is of the order of 0.2%. 

 There seem to be no previous measurements of the pressure coeffi- 

 cient for comparison. 



"X > , ,1 ,, . iili . lll 



2Q.0,1qo 20° 40° 60° 80° 100" 

 Temperature 

 .0il26fe' ' 



'V 20° 40° 60° 80° 100° 

 '^ Temperature 



Tungsten 



Figure 20. Tungsten, results for the measured resistance. The deviations 

 from linearity are given as fractions of the resistance at kg. and 0°C. Since 

 the deviations are symmetrical about the mean pressure, there is no need for 

 giving the detailed curves. The pressure coefficient is the average coefficient 

 between and 12000 kg. 



The general behavior is like that of Tantalum. When scaled to the 

 same initial resistance, the resistance-pressure curves become steeper 

 at the higher temperatures, but have less curvature. 



