The Rev. Jonn Horwz's Analysis of Satin Spar. 165 
stance was the same, and consequently that no water existed in 
its composition. 
3. The same piece of satin spar was put into the bowl of a 
tobacco-pipe, which had a cover fitly adapted to it, and exposed 
to a red heat for the space of an hourand a half. It had by this 
time assumed a black appearance, and weighed, when immedi- 
ately transferred from the crucible to the scales, 11.95 grs. of its 
original weight, or per cent. 56.25 grs. -The weight of the car- 
bonic acid expelled will, therefore, amount to 8.75 grs., or per 
cent. 43.75 grs. This Erperimen was repeated, and the result was 
the same. * : 
4. After this the 11.95 grs. were dissolved in muriatic acid: 
(but without effervescence) in a crucible of platinum, and placed 
before the fire until the volatile part was entirely evaporated. 
The crucible was then kept in a red heat for such a length of 
time, that the substance in it was fused, and afterwards, when 
cooled down to the temperature of the surrounding medium, 
became a hard, solid body of a black colour. Water was then 
added, which readily dissolved the muriate of lime contained in 
the mass, but had no effect on the other part; viz. the black 
coloured substance. When the insoluble part had subsided to 
the bottom, the clear liquor was drawn off by means of a syphon, 
and its place again supplied with pure water. "This operation 
was repeated so frequently, that when with the last decanted 
portion of water a solution of the carbonate of soda was mingled, 
no precipitate was occasioned by it. 
5. 'The black-coloured substance above mentioned being thus 
obtained apart, was folded up in a clean thin leaf of platinum, 
and heated red-hot for a short time, and when weighed as soon 
as taken from the fire, afforded at the rate of 2.6875 grs. per cent, 
after allowing for the weight of the platinum. 
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