300 
PREPARATIONS OP MANGANESE. 
intimately with one pound of finely powdered bituminous 
coal, and heating the mixture in a covered iron or earthen 
crucible for half an hour at a red heat. The presence of 
the carbonaceous matter at the high temperature, reduces 
the manganese to the state of protoxide. When cold, the 
mass is reduced to powder, and treated with ten pound of 
sulphuric acid diluted with three gallons of water till the 
oxide is dissolved out. One-sixth of the filtered solution is 
precipitated with carbonate of soda, the impure carbonate 
of manganese washed with water, added to the remain- 
der of the solution, and boiled until ferrocyanuret of potas- 
sium ceases to cause a blue precipitate when added to a 
drop of it. The liquid is then filtered, evaporated, till a 
pellicle commences to form, at a gentle heat, and set aside 
to evaporate spontaneously in shallow vessels. 
Sulphate of manganese is white, or slightly amthiest- 
colored, has a styptic taste, crystallizes in rhomboidal 
prisms, and is soluble in two and a half parts of cold water, 
and more soluble in boiling water. It is insoluble in alcohol, 
and an easy way to isolate the sulphate from its solution on 
a small scale, is to add to a saturated solution its bulk of al- 
cohol. Its amount of water of crystallization varies. 
When crystallized at or under 42° F. it contains 7 
equivalents of water ; between 45° and 68° it contains 5 
equivalents of water ; from 68° to 86°, it has but 4 equiva- 
lents of water. [Graham.) 
Syrup of Iodide of Manganese. — M. Hannon has given 
a formula for syrup of iodide of manganese, in which he 
directs a drachm of carbonate of manganese to be dissolved 
in sufficient liquid, hydriodic acid, and the solution added to 
seventeen ounces of syrup of guaiacum and sarsaparilla ; 
but this proportion is too weak, and besides is objectionable, 
on account of the menstruum, in certain cases. The follow- 
ing process gives a more concentrated solution in simple 
syrup, pure, with the exception of a small quantity of sul- 
phate of potassa, which is inert. 
