A solution of dextrine may be rendered clear by adding to each pint 1/2 drachm of alum dissolved in 3/4 oz. of water; shake thoroughly, and then add 1/4 drachm of washing soda dissolved in 1/2 oz. of water; again shake, and allow to stand for a few days. The hydrate of alumina precipitated out will carry with it the suspended matter and some of the colour, leaving the liquid much clearer and brighter.