56 Prof. D. N. Mallik and Mr. A. B. Das on Electric 



of the discharge. This is not really the case, as is seen 

 from the annexed diagram. 



B+ B 



A is the cathode, B is the anode, C the dark space. 



Curve II. is also easily explained by the fact that at a 

 lower pressure i is greater than at a higher pressure. 



15. The equation (5) shows that the angular displacement 

 of a corpuscle is proportional to H and is dependent on its 

 distance from the axis as well as on its angular position. 

 The latter explains the dispersal of the rays [10]. The 

 equation (3) also shows that there will be a time-factor ; 

 that is, the final effect will be reached only gradually. 

 Experiment bears this out also. 



16. When the pressure is further reduced, the discharge 

 becomes striatory (PI. II. fig. 13). On the introduction 

 of the magnetic field, the Faraday dark space shortens 

 in length, the number of striae increases, the distance 

 between consecutive striae decreases, and they also bulge out 

 (fig. U). 



The effect of increasing the magnetic field is to increase 

 the number of striae and further shorten the length of the 

 Faraday dark space, as well as that between consecutive 

 striae. 



17. On a still further reduction of pressure, all the striae 

 disappear and the negative glow extends from the cathode 

 to nearly the whole of the tube (fig. 15). 



At this stage, the discharge is luminous at first, but the 

 luminosity decreases as the discharge continues to pass, in 

 consequence, evidently, of a gradual recombination of ions. 



18. When the electromagnet is excited, the striae make 

 their appearance, and the tube is illuminated with a reddish 

 light (figs. 16 & 17). Fig. 17 shows the effect of increased 

 magnetic field. 



