Ligeia 
this marble contain 52 of lime, then rco parts lime take up 
169,55 of the vitriolic ftandard. 
Tue felenite thus obtained being evaporated to drynefs in a 
fand heat not exceeding 170°, was of compact, but not hard 
confiftence, felt mealy, and of a reddifh brown colour at the 
furface; it weighed 242,25 grs.; of this weight 79 were pure 
calcareous earth, 134 vitriolic flandard, 5 of foreign earth, and 
the remainder, viz. 24, were water. Hence too grs. felenite 
in this form contain 32,9 of pure earth, 55 of ftandard acid, 
and 12,1 of water; but this determination is not accurate, as the 
argil muft have taken part of the acid. 
Mr. Cavendifh having in many -inftances fought the relation 
betwixt the fpecific gravity of oil of vitriol and the quantity of 
marble it can diffolve, it will be proper to compare his refults_ 
with my table *. 
100 Parts Oil Vitriol. Marble diffolved by Marble diffolved by 
Mr. Cavendith. my Table. 
ne aug é 
1,559 54 > ¢; 
1,780 84,8 93,6 
WITH 
* Philofop. Tranfactions, 1786, p- 245, and 1788, p- 181. 
