o<;> 



Gases by the Alpha Pqrticles from Polonium. 



their power o£ producing ions. In order to determine c for 

 any one gas, the ionization (ordinate o£ the ionization curve, 

 figs. 1, 2, and 3) and the corresponding distance x of the 

 source of rays from the ionization chamber (abscissa of curve) 

 were substituted in the equation 



1 = 



(10-8-tf) 



i/a 



Fig. 3. 



The full line curves I, II, and III are the theoretical ionization curves 

 for nitrogyn, sulphur dioxide, and ether, respectively as obtained by 

 substituting the corresponding values of c given in column 2, Table I., 

 in the equation 



{r—x)V i > 



where r = 10" 



The dotted curves I, II, and III are the experimental ionization curves 

 for nitrogen, sulphur dioxide, and ether, respectively, and are plotted 

 similarly to the curves in figs. 1 and 2. 



and the equation solved for c. Separate values of c were 

 thus obtained for various distances of the source of rays 

 from the ionization chamber between <r = and ir5 centi- 

 metres, and the mean value of these separate determinations 

 found for each gas. The mean values of c as found in the 



