564 
Mr Campbell, The Radioactivity of Potassium, 
Table IV. 
Solution in water, containing 37 ’5 °/ o K 2 C0 3 . 
Density = 1 • 3887 = p. 
Area of tray — 1008 cm. 2 = tr. 
Volume of solution in tray = ax Activity = / 
55 c.c. 
39 
57 „ 
38-5 
65 „ 
38-5 
66 „ 
37-5 
70 „ 
51 
71 „ 
44-3 
79 „ 
49-5 
82 „ 
51-5 
95 „ 
60-5 
121 „ 
64-0 
135 „ 
64-3 
150 „ 
67-5 
165 „ 
62-0 
170 „ 
72-3 
193 „ 
69 0 
202 „ 
72-8 
297 „ 
76-5 
343 „ 
77-0 
Table V. 
Pure K 2 S0 4 (Kahlbaum). 
Area of tray = 1011 
cm. 2 = a. 
Mass of salt in tray = m 
Activity = / 
9-9 
15-8 
20-1 
27-1 
30-5 
44-0 
39-7 
568 
49-6 
67-5 
59-4 
76-8 
69-3 
87-1 
84-8 
98-1 
97-0 
108-7 
120-0 
131-2 
144-0 
140-0 
174-0 
157-5 
200-0 
166-1 
501-0 
202-0 
Tables IV and V give th-e measurements made. From these 
figures rough values of I 0 and A can be found by graphical methods. 
To correct these rough estimates, the following procedure was 
adopted. 
