MFTALS. 95. Magnefium. 305 



bispanicuvi. Of ^ fleel-wliite colour and luftre, emitting fulphiirous 



anci arfenical vapours and leaving a bead not attracted 

 by the maenet. 

 Fourii^ in the mine oS Arragon in Spain, and confifts of cobalt, 

 i'ulphur and arfenic without a vifible mixture of iron. 



c^S' MAGNESIUM. Dark grev gradually black- 

 ening by expolure to the air, hard, very brittle, 

 of a granular texture, atrra(5led by the magnet 

 when reduced to powder, fpecific gravity 7,000: 

 melting with ^reat difficulty, its black oxyde af- 

 fuming a green colour which in a very violent 

 heat is fufed and Converted into a green glafs, 

 when fufed with borax producing a deep red 

 glafs: Vv'hen difiolved in fulphuric acid leaving a 

 black rpongy mafs behind, and forming a red 

 precipitate with the addition of foda. 



Manganefe. 



tegulina. Staining the fingers, of a filver-grey colour with metallic 

 liiltre, and divergingly foliated texture. 

 Lapeyroufe Ail. acad Tolof i. p 256. 

 Native nnetallic mangarefe. Schmeifser z, p 251^ 

 Found in the valley of l^iedffios near Lem in the neighbourhood 

 of Foix on the Pyrenees, in kidney torm mafles: it is ilightly 

 malleable, and not attracted by the magnet. 



ochracec* Fiiab^e, without luflre or tranfparency, earthy. 

 Ochra magntfias. Sy(i. nat xii. 3 p, 194. ;;, 9, 

 M-gnefii friabilis Cronft mineral 114 

 In' 'urarcd earrhv ochre. Kirnvanminr z. p 294 

 Founa in Englundi the Pyrenees., the Tvi\x\z%o{ Franconiay and in 

 the ^//«/V mountains oi Siberia, maflive or difleminated, cel- 

 lular, porous, prforatcd, or i. various imitative forms : tex- 

 ture earthy, rareiy iinpcrfedly fluted : colour hiack:{h, or 

 brovvn like the brown haematites: fpecific gravity before it 

 has abforbed water 3,707. afier abforption 3,903. 



pBorum* Black, friable, floating, mixed dry with a fourth of its 



weight of linfeed oil producing fpontaneous inflam- 

 mation. 

 Wad, Kir<vjan miner z. p> 293. 



VOL. VII. — Qji 



