ELECTRICAL RESISTANCE UNDER PRESSURE. 



109 



of mercury at the melting point was found to be 0.2()S.3, against the 

 value, 0.272 of Guntz and Broniewski.^* Taking for the specific 

 resistance of mercury at this temperature 96.59 X 10~^ this gives 

 25.92 X 10"^ for the specific resistance of liquid gallimn at the melting 

 point. 



Three runs were made on the resistance of the licjuid as a function 

 of pressure, at 34.2°, 62.5°, and 94.4°. Before the final measurements 

 another run was made on another sample. This run had somewhat 

 greater error, but agreed with the final results within the irregularities 

 of the measurements. The resistance measurements of the liquid 

 showed a distinct hysteresis, doubtless due to the action of the glass 

 capillary. Any such effects would be expected to be especially large 

 for gallium because the pressure coefficient of resistance is so low. 

 The difference between readings with increasing and decreasing pres- 

 sure might amount to 2.5% of the maximum effect. Except for this, 

 the points lay regularly within the sensitiveness of the readings. The 

 values obtained from these three runs were smoothed in the regular 

 way, and* the resistance tabulatefl at regular intervals of temperature 

 and pressiu'e. The results are shown in Table XII. In this table 



TABLE XII. 

 Gallium. 



Relative Specific Resistances of the Liquid. 



