10 
PREPARATION OF THE SALTS OF MANGANESE. 
Mr. Phillips, (Journal of Pharmacy, vol. xii, p. 57,) recommends 
suspending deutoxide of manganese in water, and then to pass 
through it a stream of of sulphurous acid gas; thus reducing the 
deutoxide to protoxide, and converting the sulphurous acid, into 
sulphuric and hyposulphuric acids : which, uniting with the man- 
ganese, and forming soluble salts, are dissolved by the water. 
Prepared in this way the sulphate is contaminated with a certain 
amount of hyposulphate, this difficulty is obviated by boiling the 
solution for sometime, previous to evaporation. 
Another method, however, I have found to succeed better. It 
is to mix in a sand crucible, the black or deutoxide of manganese, 
with sulphuric acid, until of a thick pasty consistence ; cover with 
a smaller crucible, and expose the mixture to a red heat for half 
an hour. At the end of this interval, remove the crucible from the 
fire, and when cool, reduce the dark brown mass to a coarse pow- 
der. Introduce this powder into another crucible, and saturate as 
before with sulphuric acid. Again apply heat and continue it un- 
til white vapors cease to be expelled. By these means we obtain 
a heavy compact mass, of a light gray color, intermixed with red; 
possessing at first a pungent, but immediately followed by a sweet- 
ish, slightly astringent taste ; and soluble to a great extent in 
water. The next step of the process is to reduce this impure sulphate 
to a fine powder, and to dissolve the soluble matter, with succes- 
sive portions of water. The solution should be filtered into a por- 
celain capsule, and placed over a sand bath to heat. When near- 
ly boiling, drop into it carbonate of manganese in small portions 
at a time, until all the iron shall have been precipitated, and the 
liquid from having been of a dark red, assumes a pale rose tint. 
Filter and evaporate to the consistence of thin syrup, and set aside 
to crystallize by spontaneous evaporation. It requires from one to 
two weeks to accomplish nicely. 
When the object is to make other preparations than the sul- 
phate, it saves both time and trouble to proceed a little different- 
ly from this. Thus, instead of filtering the solution of the sub- 
stance left after the second incineration, (a process extremely te- 
dious) it is better to heat it at once, and to add bi-carbonate of 
soda in successive portions of an ounce or two at a time, stirring 
the mixture, until the iron is wholly precipitated, and a small part 
of the liquid, on being removed and filtered, appears of the appro- 
