
62 _ JONIZATION THEORY OF GASES 
This difference of conductivity in gases is due to unequal 
absorptions of the radiations. The writer has shown! that the 








RELATIVE ConDUCTIVITY 
Relative 
Gas Density i” 
‘ : : Rontgen 
a rays Brays | y rays rays 
Hydrogen ... <p 0:0693 0:226 Oslo 07169 07114 
JAE ae docs ie 1:00 1:00 1:00 1:00 1:00 
Oxygen pi ae endl 1:16 Tow Heil | ee) 
Carbon dioxide... 11958} |) se 15}7/ 1°53 1-60 
Cyanogen ... eee esos 1:94 1:86 eel 1-05 
Sulphur dioxide ... | 2°19 2°04 2°31 2°13 7:97 
Chloroform... Ps 4°32 4:44 4°89 4:88 31°9 
Methyl iodide : 5:05 3°51 518 4:80 | 72°0 
Carbon tetrachloride ) BL a ase! 5-83 5°67 45-3 


total number of ions produced by the « rays for uranium, when 
completely absorbed by different gases, is not very different. The 
following results were obtained : 
Total 
Gas Ionization 
JP” Sec fee ere ay 100 
Hydrogen ... 5a oe 95 
Oxygen es ets is 106 
Carbonic acid 4. an 96 
Hydrochloric acid gas_... 102 
Ammonia ... tts ae: 101 
The numbers, though only approximate in character, seem to 
show that the energy required to produce an ion is probably not 
very different for the various gases. Assuming that the energy 
required to produce an ion in different gases is about the same, it 
follows that the relative conductivities are proportional to the 
relative absorption of the radiations. 
A similar result has been found by M*Lennan for cathode rays. 
He proved that the ionization was directly proportional to the 
absorption of the rays in the gas, thus showing that the same 
energy is required to produce an ion in all the gases examined. 
46. Potential Gradient. The normal potential gradient 
between two charged electrodes is always disturbed when the gas 
1 Phil. Mag. p. 137, Jan. 1899. 
