by Cathode and Canal Rays to Exciting Current. 197 
justified in concluding from my experiments that it is im- 
possible to have so large a percentage of the rays reflected. 
As regards absorption by the net, I believe my observations 
show that the absorption is not directly proportional to the 
smallness of the meshes, but is related to it in some other 
way. It is desirable to have further experiments on this 
point. Further, it is not inconceivable that at low pressures 
secondary effects develop on which the above excessive values 
of the rays depend. 
Fig. 5. 
Absorption curves of canal rays in hydrogen. Fig. 6. 
Absorption curves of cathode rays in air. 

¥ 2 3 a 5 6 7 & 
Curve I. Potentials of 1300- 1400 volts. 
| Pressure of 0°2 mm. Hg. 
1. 7 1400-1500 , | Ce 1 ) potential of about 200-300 volts. 
 4iL Bi 3000— 4000 ., 1, | Pressure of 0:065 mm. He. 
& AV. < 6000-10000 ,, . ‘ ) Potential of about 2000 volts. 
ur, Pressure of 0°03 mm. Hg. 
* / Potential of about 3000-3400 volts. 
7? 
