Magnetic Field on the Discharge through a Gas. 259 



agreement with the experiments in the earlier part o£ the 

 paper. 



The appearance of the tube in the two cases is shown 

 diagrammatically in the figure. 



From the results of the experiments it was concluded (a) 

 that at pressures below \5 mm., the effect of the magnetic 

 field was to decrease the electric force near the cathode. 

 This decrease depended, as shown earlier in the paper, on the 

 strength of field and current used : at higher pressures 

 the magnet increased the electric force, (b) If the magnet 

 caused the column to striate it also caused the electric force 

 to show periodic variations. (c) The magnet generally 

 caused the electric force at the anode to increase. The 

 curve in fig. 7 is a characteristic one in this neighbourhood, 

 at pressures below 1 mm. and above "3 mm. 



Near the anode at lower pressures, in agreement with 

 "Wilson's experiments (loc. eit.) it was found that there was 

 a very small force, and in some cases one apparently negative. 



Fig. 8. 



If the direction of the field was so arranged as to pull the 

 glow on to the exploring electrodes, then the magnet was 

 found to increase the force there, so much so that a force 

 originally negative might be converted into one in the 

 opposite direction. When the glow was taken away from 

 the explorers by the action of the magnet, this negative force 



