﻿of Ions made by a, ft, y, and X Rays. 



291 



chamber, its distance from either the top or bottom being- 

 then 7 mm. 



A quantity of radium bromide, surrounded by 3 cms. o£ 

 lead, was placed at a distance of 6 cms. from the chamber. 



Table VII. gives some of the observations made. Each 

 deflexion in the table is the mean of two readings, the leak 

 of the electrometer having been, of course, subtracted from 

 each reading. 



Table VII. 



/3 Bays. 



y Bats. 



Volts 

 per cm. 



Lack of 



-n^fl^-:^,, saturation 

 Deflexion. , ,. 



and time 



of leak. 



Volts 

 per cm. 



Deflexion. 



Lack of 

 saturation 

 and time 



of leak. 



8 



Air. 80 



400 



1002 3 p. cent. 



1025 



1029 20 sec. 



6 



60 



286 



1832 

 1868 

 1S54 



1 p. cent. 

 12 sec. 



Air bubbled through 8 

 ether for 1 min. 400 



1427 5 p. cent. 

 1516 20 sec. 



6 



286 



1768 



1832 



3 p. cent. 



9 sec. 



C0 2 passed into 8 

 chamber. ! 400 



1502 

 1505 



20 sec. 







Ethyl chloride 



passed into 



chamber. 



8 



80 



400 



1734 

 1834 

 1918 



9 p. cent. 

 4 „ 



16 sec. 



6 1639 

 60 1760 



286 1841 

 536 1865 



12 p. cent. 



6 „ 

 1 ., 



7 sec. 



Air. 



Uranium covered 



with an additional 



thickness of '7 mm. 



of aluminium. 



8 

 80 



! 



1546 



1528 3 min. 









It will be seen that the initial recombination of the ions 

 made by y rays is also small. 



With a. rays the lack of saturation is greater the denser 

 the gas, and although the lack of saturation is small in gases 

 ionized by ft, y, or X rays, it is also more marked the denser 

 the gas. 



Eve has shown that the secondary rays from a metal plate 

 on which 7 rays fall consist in part of projected electrons of 

 great penetrating power; and it is very probable, therefore, 

 that the ejected electrons in a gas ionized by y rays possess 

 a velocity of the same order, which enables them to get well 

 aw T ay from their parent molecules. 



U2 



