46 
MANBAM PIOXIDUM PRDCIPITAIOI. 
Precipitated Manganese Dioxide. 
To replace Mangani Dioxidum. U. 6. Pharmacopoeia, It con- 
sist" chief v of manganese dioxide MnO . with "mall amounts of 
other oxides of manganese, corresponding to not less than 50 per cent 
of manganese dioxide. The Mangani Dioxidum 1-SOOi was the native 
■ rude manganese dioxide and was only required to contain at least 66 
per cent of the pure dioxide. 
Dose. — “Average dose: 0.250 Cim. = 250 milligrammes (4 grain" . 
(U. s. p.) 
M A \<. \M HTP0PH0SPHIS. 
Manganese Hypopliosphite. 
Ain PH,0 2 )j — Hy> 
It should contain not less than 07 per cent of pure manganese 
hypophosp hit e . 
Dose. — “Average dose: 0.200 Gm. =200 milligrammes : grains;.'' 
(U. S. P.) 
It is contained in Syrupns Hvpophosphitmn Compositus. 
MPTHYLTHIOMN.E HYDK0C HLORYDUM. 
Metkyltliioniiie Hydrochloride. 
Methylene Blue. 
Wgsci 
Chemically, it is tetramethylthionine hydrochloride. 
Properties. — Dark, green, crystalline powder, or prismatic crystals 
having' a bronze-like luster. 
Readily soluble in water, somewhat less so in alcohol: the solutions 
are of a deep blue color. 
Incompatible with potassium iodide. Reducing agents decolorize it. 
Dose. — 'Average dose: 6.250 dm. = 25o milligrammes ± grains)." 
(U. S. P.) 
Caution. — Not to be confounded with commercial methylene blue, 
which is often the zinc chloride double salt of tetramethylthionine. is 
employed as a dye or "tain, and is unlit for internal administration. 
Methylene azure, a dye which has recently come into prominence as 
a "tain in histology Romanowsky's "tain, for example, depend" upon 
the methylene azure present in "ripened" methylene blue), is derived 
from methvlene blue bv the addition of two atoms of oxvo-en to the 
t. «_ «- » ; 
sulphur. 
^ ^ XCCITj), N(CH 3 ) 2 
* N-CH ICl * ^CH CH : uCl 
Methylene t Ice 
Methylene azure hlorlde 
