FIXED ALKALIES AND ALKALINE EARTHS. 



The carbonate of lime precipitated, being 

 washed and dried, weighed just 6-5 grains, or 

 exactly the same as the calcareous spar originally 

 dissolved in the muriatic acid. It was obviously 

 a compound of'all the lime in 6'&5 grains of 

 calcareous spar, and all the carbonic acid in 

 8 75 grains of anhydrous carbonate of potash. 



This carbonate of potash had been procured 

 by exposing pure crystals of bicarbonate of 

 potash to a red heat in a platinum crucible. It 

 has been ascertained that this carbonate is an- 

 hydrous, and that it is a compound of 



1 atom carbonic acid = 2 '75 

 1 atom potash = 6 



8-75 



From this it is obvious, that the 6 '25 of carbon- 

 ate of lime contained just 2'75 of carbonic acid, 

 the remainder being lime, it is evident, that this 

 carbonate is composed of 



Carbonic acid 2-75 

 Lime 3-50 



6-25 



2*75 being the atomic weight of carbonic acid, 

 and the salt being neutral, 3*5 must be the 

 weight of an atom of lime. It is clear likewise, 

 that calcareous spar is a compound of one atom 

 carbonic acid and one atom lime. 



