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CLASS IV. METALS. 



A. Malleable, 



80. Platinum* Silvery-white; very hard and tenacious; 



fonorous ; exceedingly malleable and 

 ductile; not melting in a white heat; 

 fohible only in 16 times its weight of 

 boiling nitro-muriaiic acid, and giving 

 fiiil a yellow and then a deeper red or 

 brown colour to the folution: fpecific 

 gravity 23,000* 



81. AuRUM. Reddiih-yellow ; hardifh and tenacious; 



not fonorous; exceedingly malleable and 

 du6^ile ; melting in a white heat ; foluble 

 only in nitro- muriatic acid, and giving 

 the folution a yellow colour: fpecific gra- 

 vity 10,300. 



82. Argentum. Silvery-white; hard and tenacious; fono- 



rous; exceedingly malleable and du6tile; 

 melting in a white heat; foluble in nitric 

 acid, and imparting no colour to the folu- 

 tion : fpecific gravity 10,500. 



83. Hydragyrum. Silvery-wnite; fluid at the common tempe- 



rature of the atmofphere ; malleable when 

 ' rendered folid by a fufficient degree of 

 cold; evaporating in heat; foluble in mi- 

 neral acids, and imparting no colour to the 

 folution: fpecific gravity 13,568. 



84. Cuprum. Fine red; bird and tenacious; fonorous; 



malleable and ductile ; when expofed to a 

 red heat taking fire and emitting a mod 

 brilliant lively green li.iJ;ht; exploding vi- 

 olently when melted and caft into water: 

 fpecific gravity 6,607. 



VOL. Vir, — Hh 



