ALUM

one of a series of double ple | which the sulphate of aluminium { was | with alkaline sulphates. The most. mon is potash alum, which lem pe rith | the sulphates of aluminium P ion, | slum, and may be bashes by dis so ‘ted | the two sulphates together, and allo It | the compound salt to crystallize out of | is produced on on extensive scale his of in Yorkshire, and in Glasgov to! rig be as an astringent in med: fore and has, in addition, many commercial | Thus it is employed in the manufactu 2 in | fast colours, as a mordant in dye in [ed- | calico printing, paper making, and t pies | binding. Other common alums are ind, | alam, and ammonia alum, the latt ow-| Which is extensively OD age on fron the ammoniacal waste gas works, the | is used as a substitute for potash alun ine,| [s. 41]