162 Wisconsin Academy of Sciences, Arts, and Letters. 
tioned reasons and adds the possible insoluble impurities in the ar¬ 
senic trioxide used. The impurities in the arsenic trioxide used 
are also emphasized by Glueeksman. 63 Chumaceiro 64 refers to the 
“International Formula” 65 for preparing a clear permanent solu¬ 
tion. This evidently eliminates the alkalinity. Moreover this 
formula directs that spirit of lavender be used in place of the tinc¬ 
ture. However the finished product in this case is not a solution 
of an arsenite, 65 
The strength of Fowler’s Solution is based on the arsenic trioxide 
content. That a gradual oxidation of the trivalent arsenic to the 
pentavalent arsenic takes place is generally accepted. The cause 
of this oxidation however, has called forth some considerable in¬ 
vestigation and comment. Apparently all investigators agree that 
the introduction of atmospheric oxygen, in various ways, is the 
direct cause, but the conditions which accelerate or retard such 
oxidation seem to offer a source of disagreement. G. Kassner 66 
attributes the oxidation to the introduction of atmospheric oxygen, 
but does not mention any conditions influencing the rate. C. 
Feuer 67 claims that the oxidation due to atmospheric oxygen is 
slight within a half year’s time, and that the alkalinity of the solu¬ 
tion accelerates this change. Fosenthaler 68 merely points out that 
oxidation of arsenous acid takes place. Lyons 69 claims that under 
like conditions the greatest amount of oxidation takes place in an 
alkaline solution, the least in an acid solution, while in a solution 
containing the (HC0 3 ) radicle the rate of oxidation lies between 
the two. In a later publication Lyons 70 claims that no oxidation 
takes place in an acid solution. L. A. Brown 71 suggests keeping 
the solution in small well filled and closed containers to prevent 
63 Pharm. Post., 29, p. 353 (1896.) 
64 Ibid. 52, p. 323 (1908.) 
65 According to the “International Formula” as given in this article, “spirit 
of lavender (colorless distillate)” is used in place of the Compound Tincture of 
Lavender U. S. P. Also some diluted hydrochloric acid is added, 3.5 grams 
(13.67 p. c.) to 1 gram of potassium carbonate. This represents 0.458 grams 
HC1, which requires 1.72 grams of potassium carbonate for neutralization. As 
only 1 gram of potassium carbonate is used evidently the finished product is an 
acid solution. 
« 8 Pharm. Ztg., 34, p. 419 (1889.) 
«Pharm. Post., 28, p. 381 (1895.) 
68 Pharm. Centralh., 47, p. 850 (1906.) 
« 9 Proc. A. Ph. A., 56, p. 901 (1908.) 
70 Proc. A. Ph. A., 57, p. 904 (1909.) 
71 Ky. Agr. Exp. Sta. Bull. No. 150, p. 153 (1910.) 
