118 
ME. W. R. BOUSFIELD: TOXIC SIZE IN RELATION TO 
variations of ionic size.* The coefficient of ionisation thus corrected according to our 
© 
theory takes the form given above in equation (7). 
In the case of NaCl it is now found that a similar accord with the law expressed 
in equation (13) can be obtained with a function of the same form and a value of 
B = 2‘8. This is shown in the following table in which are given corresponding 
values of m, X, log h, 7?, and the other magnitudes involved. The values of r\ are 
denied from large scale diagrams of the observed values. For obtaining the values of 
a there is taken the series of values of X given by Kohlrausch (‘ Sitz. der Iv. Preuss. 
Akad. der Wiss. zu Berlin,’ 1900, p. 1002), A = 108’99. The corrected values of a 
are calculated by means of equation (7) with the value for <T = 2-8 h~ 23 . The column 
headed C gives the value of the constant C in equation (13) as calculated from these 
data. The column headed AO shows the difference of C from the mean value 0'5049 
(which is arrived at without reference to the value for in — O'OOOl, for the reasons 
given in the former paper). 
Table VIII. 
7)1. 
Log h. 
A. 
'/■t 
A i] 
G. 
AC. 
AX. 
A 1 + <f> 
0-0001 
5-74374 
108-10 
1-0004 
0-9918 
0-5274 
+ 0-0225 
-0-07 
0-0002 
5-44271 
107-82 
1-0007 
0-9893 
0-5052 
+ 0-0003 
+ 
0-0005 
5-04477 
107-18 
1-0011 
0-9833 
0-5041 
-0-0008 
+ 
o-ooi 
4-74375 
106-49 
1-0014 
0•9765 
0-5056 
+ 0-0007 
-o-oi 
0-002 
4-44271 
105-55 
1-0018 
0-9672 
0-5060 
+ 0-0011 
-o-oi 
0-005 
4-04475 
103-78 
1-0029 
0-9495 
0-5038 
-0-0011 
+ 0-02 
o-oi 
3-74368 
101-95 
1-0041 
0•9309 
0-5053 
+ 0-0004 
-o-oi 
0-02 
3-44259 
99-62 
1-0055 
0-9064 
0-5044 
-0-0005 
+ 0-03 
0-05 
3-04444 
95-71 
1-0087 
0-8632 
0-5028 
-0-0021 
+ 0-09 
o-i 
2-74304 
92-02 
1-0126 
0-8189 
0-5064 
+ 0-0015 
-0-08 
0-2 
2-44131 
87-73 
1-0184 
0-7680 
0-5048 
-o-oooi 
+ 0-01 
0-5 
2-04105 
80-94 
1-0408 
0-6889 
0-5041 
-0-0008 
+ 0 "05 
1-0 
1-73592 
74-35 
1-0857 
0-6198 
0-5064 
+ 0-0015 
-0-12 
1 
The column headed AX shows the difference between the observed and calculated 
\ alue of X, v orked out (as in the former paper) from AC. The differences are some¬ 
what more uneven than in the case of KOI, owing partly to the fact that the viscosity 
correction is larger and probably less accurate, and partly to the fact that the 
function B h - :i does not quite so well represent the correction. But the accurate 
correspondence of the experimental values with the modified Van’t Hoff* law is in 
this case brought down to normal solutions, within the limits of experimental error; 
and the divergence is nowhere so great as one per thousand except on the extreme 
figure. Ihe following table shows the values of a for KOI and NaCl calculated in the 
ordinary way and the values of a calculated from equation (7) or equation (13). 
* As to this hypothesis, vide Appendix, p. 155. 
t Referred to water as unity. 
