Of the furnace must be so% greater than that of the kettle into which the softened lead is tapped, as the dross and skimmings formed amount to about so% of the weight of the lead charged.
Browne finds that after smoking " chandoo," containing 8.98% of morphine, 7.63% was left in the dross, so that only 1.35% of morphia was carried over in the smoke or decomposed by the heat.
The last distinctive epithet was derived from the little hamlet in the vicinity which furnished shelter, not only to the workmen, but to the monks of St Jerome who were afterwards to be in possession of the monastery; and the hamlet itself is generally but perhaps erroneously supposed to be indebted for its name to the scoriae or dross of certain old iron mines.
The lead is melted down slowly, when the impurities separate in the form of a scum (dross), which is easily removed.
For smoking the Chinese use an extract of opium known as prepared opium or chandoo, and a cheaper preparation is made from 60% used opium known as " opium dross " and 40% native opium.