EE Ee- aS Se

AS A MANURE, 57

POST SCRIPT

Directions for afcertaining the purity of Lime, and difcovering the Nature of the Bodies that may be mixed with it,

ee In the preceding Effay, I have fuppofed

that no other abjorbent* earth is ever nixed with the calcaresus in any fort of lime-{ftone;—becaufe, in fa, if ever any of thefe are mixed with the calcareous in thefe fubffances, they are in fuch{mall proportion as not to be worth regarding. —Thofe, however, who want to be criti- cally exact in their analyfis of lime-ftone, may difcover if there is any other fort of abforbent earth contained in it, by drop-

. ping into the filtred{olution obtained by

the procefs§ 13, p. 508, a few drops of a Clear folution of volatile alkali.—If no turbidnefs enfue, the calcareous earth has been pure-—If any precipitation takes

* Abforbent earths are all thofe that unite with acids, of which there are feveral varieties; calcareous earths being one of thefe.

5 place