2) is employed, in which the absorbent is protected by a second pipette containing water.
In special cases, such as the preparation of edible oils and fats, a further improvement in colour and greater purity is obtained by filtering the oils over charcoal, or over natural absorbent earths, such as fuller's earth.
Large quantities of ground mica are used in the manufacture of wall-paper, and to produce a frosted effect on toys, stage scenery, &c. Powdered mica is also used in the manufacture of paints and paper, as a lubricant, and as an absorbent of nitro-glycerine and disinfectants.
During this season the rivers, which are roaring torrents throughout the monsoon, are almost all lost in the dry, absorbent plains.
The same absorbent' quantitatively takes up any halogen and sulphur which may be present.