MINERALOGY. n 



I, With the acid of common fait they make 

 a fal ammoniacum fixum, which alfo 

 partly precipitates itfelf. 



c. The'acid of nitre dhTolves them perfect- 

 ly, and does not part with them again, 

 unlefs fome alcaline fait is added. 



6. They melt eafily with borax into a glafs, 

 which fuffers impreflions in a degree of heat 

 below ignition. 



7. They likewife fufe into a glafs with fal fit- 

 fibile microccfmicum with an effervefcence *. 



8. They melt the readied of all kinds offtones, 

 with the calces, into a corrofive glafs or 

 flag. 



9. They have alfo fome power of reducing cer- 

 tain metallic earths or calces -, for inftance, 

 thofe of lead and of bifmuth, and likewife, 

 though in a lefs degree, thofe of copper and 

 of iron : thus 



jo. Do they, in this laft mentioned article 

 (9.% as well as in other circumftances, re- 

 femble a fixed alcaline fait ; from whence 

 alfo this whole kind is very often, and pro- 

 perly, called alcaline earths. 



1 1 . This whole order of earths is common to 

 all the three kingdoms of nature •, bccaufe it 

 is found in the bones and (hells of animals, 

 as well as in the afhes of burnt vegetables ; 

 it mud, confequently, have exifted before 

 any living or vegetable fubilance •, and is, no 

 doubt, proportionable to its univerfal ufe, 

 diftributed throughout the whole globe. 



* It is to be underftood, that this effervefcence is alfo made 

 with the borax, as well as with this jalfufibile microccfmicum ; 

 and it is alfo to be obferved, that the glaiTcs made with thefe 

 felts are quite colourlefa and trarifparent. 



SECT. 



