QUESTIONS TOUCHING MINERALS. 403 



salt of lead ; this salt, or as some name it, sulphur, may be 

 turned into perfect lead, by melting it with the like quan- 

 tity of lead which contains principles only for itself. 



I acknowledge that there is quicksilver and brimstone 

 found in the imperfect minerals ; but those are nature's 

 remote materials, and not the chemist's principles. As if 

 you dissolve antimony by aqua regia,ihere will be real brim- 

 stone swimming upon the water : as appears by the colour 

 of the fire when it is burnt, and by the smell. 



The third letter of the cross-row, touching the variation of 

 metals into several shapes, bodies, or natures, the par- 

 ticulars whereof follow. 



Tincture. 

 Turning to rust. 

 Calcination. 

 Sublimation. 

 Precipitation. 

 Amalgamating, or turn- 

 ing into a soft body. 

 Vitrification. 



Opening or dissolving into 

 liquor. 



Sproutings, or branchings, 

 or arborescents. 



Induration and mollifica- 

 tion. 



Making tough or brittle. 



Volatility and fixation. 



Transmutation, or version. 



For tincture; it is to be enquired how metal may be 

 tinged through and through, and with what, and into 

 what colours ; as tinging silver yellow, tinging coppei 

 white, and tinging red, green, blue ; especially with 

 keeping the lustre. 



Item, tincture of glasses. 



Item, tincture of marble, flint, or other stone. 



For turning into rust, two things are chiefly to be en- 

 quired ; by what corrosives ] it is done, and into what 



1 cvrasives in orig. 



