54 Proceedings of the Royal Society of Edinburgh. [Sess. 
through a maximum to decrease near c — 1, hut u 0 steadily increased. He 
was unable to prove definitely the existence of negative adsorption even 
in very concentrated solutions (c = 096) with acetic acid and charcoal, but 
obtained it easily with acetic acid and silica, and subsequently * with blood 
charcoal and aqueous solutions of potassium chloride and magnesium 
sulphate. 
Dora Schmidt- Walter,*)* as a result of the author’s criticism of Schmidt’s 
papers, tried “ to find the influence of the solvent on adsorption,” using 
charcoal and acetic acid in various solvents at great concentrations. 
Following Schmidt, she calculates first u 0 (l—c) — c 2 in Table VII — and 
then by making successive allowances for the amount adsorbed from the 
Table VII. 
C 1 
C 2 
C 3 
1-55 
0-439 
0-45 
3-68 
•62 
•64 
9-09 
•90 
•99 
18T 
1-08 
1-2 
396 
-0-225 
-0-37 
58-0 
-0*522 
-1-2 
68*4 
-0-497 
-1-6 
85-4 
-0-633 
-4-3 
mass of the solution works back to u 0 — c 3 in the table. Her observations 
with water, benzene, and toluene may justifiably be regarded as confirming 
the author’s views. In Table YII are presented her observations with 
toluene as solvent. c 3 has been calculated by the author, using c 3 == > 
where cq is the percentage of acetic acid in the solution. In her curves 
she makes the correct assumption that c 2 = 0 when ^ = 100. Fig. 2 
reproduces her toluene results. She does not graph (u 0 , c), and by con- 
fusing the author’s u 0 with u she attempts to defend Schmidt, and incident- 
ally annexes without acknowledgment certain of the author’s views. 
This is pointed out by Gustafson,} who states, “ It may now be regarded as 
beyond doubt that the u 0 curve runs in the manner indicated by Williams.” 
Gustafson obtained negative adsorption with phenol in alcoholic solution 
and generally confirmed the author’s views. 
Osaka, § working with aqueous solutions of different salts and blood 
* Trans. Farad. Soc. (1914), x, p. 155. 
t Roll. Zeits. (1914), xiv, p. 242. 
X Zeits. f. physik. Chem. (1916), xci, p. 385. 
§ Mem. Coll. Sci. Kyoto (1915), i, p. 257. 
