Chap. 33.] Mercury in a jolid State. 205 



confiderable malleability, but this cannot be proved 

 to its fulleft extent, becaufe the hammering' of it 

 produces very foon a degree of heat fufficient to 

 melt it. 



Mercury being a metal in a ftate of fufion, always 

 affects the form of globules when it is divided j and 

 when it is confined in a bottle, its furface is convex, 

 from the ftrong attraction of its particles for each 

 other. If the veffel, however, in which me/cury is 

 confined, is metallic^ its furface appears concave, from 

 the tendency which it has to unite itfelf to the fides of 

 the veflel, which attraction overcomes that between 

 its own particles. 



When mercury is'fubrnitted to that degree of heat 

 at which it is volatilized, and is at the fame time ex- 

 pofed to the action of atmofpherical air, it is gradually 

 converted into a calx of a red colour, the hydrargyrus 

 calcinatus of the London Pharmacopeia. A greater 

 heat, however, revives this metallic calx, and at the 

 fame time the vital air is again extricated. 



Mercury is not fenfibly acted on by expofure to 

 air, but by long continued agitation it becomes .partly 

 converted into a very fine black powder. The mer- 

 cury is not changed in this experiment, unlefs, per- 

 haps, it fhould be. found that it abforbs ibme part of 

 the vital air contained in the veffel in which it is con- 

 fined. By a flight heat, or by trituration in a warm 

 mortar, it may be made to refume its ufual fluidity and 

 brilliancy. 



Mercury is found in the earth, either in its native 

 .metalic ftate, or combined with fulphur, when it is 

 called cinnabar. Running mercury is found in glo- 

 bules, or larger maflfes, in friable earths or ftones, and 

 moft commonly in the clefts or cavities of its ores. It 

 is more frequently, however, imbedded in calcareous 



earths 



