324 New method of decomposing Silicates. ' 
off the water of oe The pure chlorid of barium 
thus obtained is pulverized and is then ready to be used for 
the purpose here sadonsth 
Chlorid of barium>may be pan in a platinum crucible by a 
blast lamp, or by an alcohol blowpipe la amp. A mixte ire of chlo- 
‘ rid of -batium and chlorid of strontium: in atomic proportions 
_ fuses however far more easily than eitker of its ingredients. 
Such a mixture is fused by the heat of an ordinary Berzelius 
lamp, and more easily, I think, than.carbonate of soda. This is 
analogous to the well known fact. that’a mixture of carbonate of 
although sulphate of strontia when precipitated by itself, appears 
_ ina form somewhat gelatinous, tedious to wash and difficult to - 
a - filter, yet when precipitated in the presence of sulphate of ba- 
~ rytay it takes on the finely granular form of the latter, and the — 
~ combined sulphates are as easily washed as the sulphate of baryta * 
e when precipitated alone. 7 
. . "The atomic proportions of a mixture of chlorid of barium and 
* . chlorid of strontium,, suitable for the fusion “« silicates, are about 
four parts of the former to three of the latte 
The best mode of proceeding was found 6 be-as follows :— 
The mineral in fine powder is intimately mixed with four or 
five times its weight of chlorid of barium, or of the mixture of 
chlorid of barium and ehlorid of strontium, ina platinum eruci- 
. ble; which is then covered, and exposed to a heat sufficient to 
fus mass for twenty or thirty minutes. When cool, the mass 
is iiepued by bending the crucible, and allowed to fall intoa « 
beaker glass. Water is then poured on ‘it in’ sufficient ewcmek 
to dissolve the excess of chlorid of barium, oF ee of strontium, 
Gaal teh hees toe tecooemeneatey 
