NATURAL HISTORY OF LEAD.

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PART L.

SECT. I.

NATURAL HISTORY OF LEAD;

T. HIS metal is found in considerable quantity in many partsof the earth. It is found in nature in different states, seldom ifat all in the metallic state. It is found in that of an oxid, redlead ore, mixed with a portion of iron, clay, and other earths.

The colour of this ore is aurora red, resembling red arsenic.It is found in small lumps of an indeterminate figure, and alsocrystallized in four-sided rhomboidal prisms.

Combined with carbonic acid it forms the sparry lead ore, socalled because it has the texture and crystallization of certainspars. There are a great many varieties of this kind. It is foundunited with sulphuric, phosphoric, arsenic, molybdic, and chro-mic acids. Lastly, lead is found mineralized by sulphur form-ing what is called galena (sulphuret of lead) which is by far itsmost abundant ore. This ore which is very common is foundboth in masses and crystals.

The primitive form of its crystals is a cube. Its colour is of abluish lead grey. It has a considerable metallic lustre, its tex-ture is foliated. It stains the fingers, and often feels greasy,c ontains in general a minute quantity of silver.