This filter bag is composed of woven fabric alternated with paper, the whole securely fastened together to form a solid sheet.

It is indeed a good filtering bag, and will quickly and thoroughly remove suspended particles and render water bright and clear.

But these filters do not act on the impurities in solution. If such are present in water precipitate them first and then call these filters into service. Should organic impurities be held in solution a charcoal filter is to be put in requisition or aerating has to be resorted to. These filtering bags, however, are very well adapted for filtering wine, cider, spirits, fluid extracts or essences, etc.

Fig. 25.  Derham's Patent Filter Bag

Fig. 25.- Derham's Patent Filter Bag.