C 389 ] 



acid, verdigris; — with volatile alkali, tinfhire of 

 copper; — with fal ammoniack, ammoniacal copper. 

 Thefe are the principal preparations of copper that 

 are now in ufe for medicinal purpofes: they ad as 

 powerful tonicks, fedatives, and aftringents, and 

 become ufcful remedies, or virulent poifons, ac- 

 cording as they are managed. Externally they are 

 employed as efcharoticks, for deterging foul ulcers, 

 and difpofing them to heal. Internally they are 

 fometimes given in the hyfterick, epileptic, inter- 

 mittent, and other nervous difeafes, but ought 

 never to be adminiftered without the utmoft caution. 

 Verdcgris, being the mod intradlable of the whole 

 clafs, has long been confined to external ufe, ex- 

 cept for the purpofe of expelling arfenick and other 

 fatal poifons. It is generally rejected the moment 

 it comes in contad with the ftomach, and is perhaps 

 one of the mod inftantaneous emeticks in nature i 

 but as it operates with great vehemence, it perhaps 

 ought not to be hazarded even in thefe cafes, efpe- 

 cially when the inflammation may be fuppofed to 

 have already made a confiderable progrefs. 



In various Arts, 



This and other preparations of copper are highly 



efteemed in the arts, for the beautiful blues and vivid 



greens which they communicate to various fub- 



ftances, and are therefore frequently employed in 



C c 3 painting 



