Currents arising from hod fine heated Platinum Wires. 945 



respective galvanometer deflexions obtained on rotating the 

 plane of the wires through 90° from its initial horizontal 

 position, for which position the bridge was initially balanced, 

 are plotted as ordinates against the corresponding distances 

 apart of the wires as abscissae. The heating current 

 employed was 1 000 amp., and in each case the plane of the 

 wires was rotated so that the movable wire was placed above 

 the central wire. It is seen from fig. 2 that as the distance 

 between the wires increases from zero, galvanometer 

 deflexion occurring on rotation of the wires through 90° 

 increases until a maximum deflexion of 2G0 is attained at P', 

 corresponding to a distance apart of the wires equal to 

 0*170 cm. Thereafter the deflexion decreases somewhat 

 less rapidly than the previous rate of increase to the 

 maximum, and attains the value zero at Q' corresponding to 

 a distance apart of the wires equal to 0*60 cm. With 

 increasing distance apart of the wires, the galvanometer 

 deflexion is reversed and attains a maximum negative value 

 equal to 175 scale divisions at B/, corresponding to a distance 

 apart of the wires equal to 1*8 cm. With further increase 



DiSTANCE BETWEEN WIRE3 (CMS 



in the distance apart of the wires, the negative deflexion 

 diminishes very slowly. The curve in fig. 2 is best dis- 

 cussed in the light of the curves given in fig. 3, which show 



