[ «; 3 



fixed air will fly off, and the chalk be precipi- 

 tated. 



d. By adding a folution of foap, the fame 

 appearances will take place, as in water con- 

 taining Epfom fait, defcribed (page 56, e.) 



By adding a folution of filver in nitrous acid, 

 or of mercury in nitrous acid, or of lead in acet- 

 ous acid, or of blue vitriol, or by adding fpirit of 

 wine, the fame appearances will be produced as 

 upon adding thefe fubftances to water containing 

 Epfom falts, defcribed (page 57, h. i. k, 1. m.) 



B, e. The acid may be detected by the fame 

 means, and with the fame appearances as defcrib- 

 ed (page 53 and 54, a. b. c.) 



CHALK. 



Calcareous Earth combined with fixed Air* 



Synonymous Names. 

 fCreta. 



Cretaceous earth A Sec. or 

 J Calcareous earth. 

 CHALK. ^ Calcareous fpar. 



I' Calcareous carbonate. 

 Carbonate of lime. 

 ^Aerated lime. 



This is found in immenfe quantities in moft 

 parts of the earth 5 at leaft the fuperfkial parts ; of 

 courfe is found diffolved in almoft all fpring 

 waters* 



K 2 A. a. 



