142 Wisconsin Academy of Sciences, Arts, and Letters. 
tury. 5 Still later followed the organic derivatives of arsenic that 
formed the basis of the classical researches by Bunsen. 6 7 Com¬ 
paratively few of these have found application in medicine, one of 
the latest being the much discussed specific “606” or salvarsam. 1 
If the chemotherapy of arsenic includes but few of its com¬ 
pounds, pharmacopoeial preparations of the derivatives of this ele¬ 
ment are even less numerous. Those of the U. S. P. and N. F. are 
but seven in number and can be grouped as follows: 
1. ) Solutions of arsenous acid and its salts: 
1. ) Liquor Acidi Arsenosi, U. S. P. 
2. ) Liquor Potassii Arsenitis, U. S. P. 
2. ) Solutions of arsenates: 
3. ) Liquor Sodii Arsenatis, U. S. P. 
4. ) Liquor Sodii Arsenatis, Pearson, N. F. 
5. ) Liquor Arsenicalis, Clemen’s, N. F. 
3. ) Solutions of arsenic trihalides (or rather “double salts”) : 
6. ) Liquor Arseni et Hydrargyri lodidi, U. S. P. 
7. ) Liquor Auri et Arseni Bromidi, N. F. 
I. Solutions of Arsenous Acid and Its Salts. 
The socalled “arsenious acid” of the older chemists, our arsenous 
acid anhydride, or arsenic trioxide, is but sparingly soluble in wa¬ 
ter, yet sufficiently soluble to form solutions with a 1 p. c. As 2 0 3 
content. Nevertheless such a solution is not official in any of the 
latest editions of the pharmacopoeias. 8 9 Neither does the simple 
solution appear to be prescribed at present by physicians, although 
arsenic trioxide is frequently prescribed in solid form as pill,® 
°Kopp Geschichte der Chemie, 4, p. 96. 
6 The reprint of these has been edited by A. v. Baeyer in Ostwald’s Klassiker 
der exakten Wissenschaften. vol. 27. 
7 This epoch making discovery is discussed by Schweizer “Ehrlich’s Chemo¬ 
therapy—a new science” in Science, vol. 32, p. 809. (Dec. 9, 1910.) 
8 In the French Codex of 1884 a Solute Arsenical ou Mineral (Boudin), one- 
tenth as strong as the corresponding U. S. P. arsenical solution, was official, 
but has been dropped in the latest edition. See also Dorvault, L’Offfcine, 15th 
edition (1910), p. 1289, which also gives a formula for a Solute Arsenical (Is- 
nard), which is only one-tenth of the strength of Boudin’s solution. 
9 Arsenic trioxide enters the Pilulae Ferri, Quininae, Strychninae et Arseni 
fortiores of the National Formulary 4th revision; also Pilulae F. Q. S. et As. 
mites , N. F. IV with less arsenic trioxide. 
The French Codex of 1866 and 1884, but not the latest edition, contains. 
Granules d’ Acide Arsenieux; also Pilules Arsenicales (Pilules Asiatiques); see 
also, L’Officine 15th edition (1910), p. 1061; Binz, Lectures on Pharmacology, 
vol. 2, (1897), p. 88, translation by Latham. 
