I 
' - ' - / ■ : : • 
:m. * 
• ’,A 
• fts 
8Z MINERALOGI0AL 
and then weighed 93 grains: it was af¬ 
terwards treated with 3 times its weight 
of concentrated oil of vitriol, and evapo¬ 
rated nearly to drynefs in a fand-bath, 
then re-diffolved in water and filtred. 
1 1 • , * 
There then Remained 26 grains of an in- 
diffoluble earth, which was filex: when 
this was mixed with mineral alkali, and 
melted with the blow-pipe, it fwellecl 
and gave a clear globule of glafs. 
I have feveral times obferved filiceous 
parth along with other earths diffolved in 
acids: this fhould fugged how cautious a 
chemift ought to be in analyzing different 
kinds of ftones and earths. 
? • > •" ' . V 1 • ‘1 - ’ - - * - • > 
I 5* 
The vitriolic folution contained there¬ 
fore the remaining 67 grains, which, pre¬ 
cipitated by alkali and examined, was ar¬ 
gillaceous earth* 
- § 6 . 
V 
