The oxides in the thoroughly roasted ore will not amalgamate with mercury, and are not acted on by chlorine or cyanogen.

Unless the metal of which they are composed will not readily amalgamate with mercury, I should be chary of using new screen devices.

In Fuller's bichromate cell the zinc is amalgamated with mercury, which is kept in a pool beside it by means of a porous pot.

The methods employed are multitudinous, but may be divided into four classes, namely, washing, amalgamating with mercury, chlorinating, cyaniding and other leaching processes, and smelting.