method of obtaining lead.

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must be fused in a blast furnace. The lead is by that means se-parated, and cast into iron moulds, each of which contains aportion called a pig of lead These pigs are sold under yhe nameof ore lead.

To disengage the silver from lead thus obtained, the metal issubjected to the action of the refining furnace. The continualapplication of a quantity of fresh air which is thrown by meansof large bellows upon the fused lead, which is at the same timeheated as intensely as possibly, oxidates the lead, and convertsit into the yellow scaly oxid, known by the name of lytharge.

This scaly oxid being driven off from the surface 'of the fusedmetal, as it is formed, leaves the silver alone unaltered at thebottom.

The lytharge is then to be fused in contact with charcoal, thatit may assume the properties of metallic lead.

In order to obtain perfectly pure lead, the lead of commercemay be dissolved in pure nitric acid, and the solution be decom-posed by adding to it, gradually, a solution of sulphate of soda,so long as a precipitate ensues. This precipitate, which is sul-phate of lead, must then be collected on a filter, washed re-peatedly in distilled water, and then dried. In order to reduceit to its metallic state, let it be mixed with two or three timesits weight of black flux, introduce the mixture into a crucible,and expose it briskly to a red heat.