Magnesium, METALLURGY

OF. It is very difficult to extract from its combinations. Davy first obtained the metal, decomposing the chloride by electrolysis in 1808. It was isolated by Bu y 1849, by acting on magnesium chloride with pota ium. Three years later, Bunsen decomposed fused magnesium chloride by an electric current, opening up a new way of obtaining this and similar metals. It is now obtained by a similar proce at He mel in gen. The carnallite from Sta furt is melted in iron pots, which serve as the negative pole of the apparatus, while a carbon rod serves as anode. The chlorine evolved at the anode is carried away by a tube surrounding it, and utilized; the magnesium collects on the sides of the pot, rises to the surface, and is skimmed off by perforated ladles. The metal is kept from burning by reducing gases led in under the cover. The principal uses are for flashlight photography and in pyrotechnics.