A Specific Knowledge Desired. - Mechanical Filters. - Chemical Filters. - Various Patent Filters. - The National Filter. - The Hyatt Filter. - Bige- low-Curtis Filter. - The Tank Filter. - Billich Filter. - The Wagner Charcoal Filter. - De Lisser's Power Filter. - Jewett Filter. - Baker's Filter and Compound. - Johnson Pressure Filter. - Puffer's Sponge Filter. - Globe Pressure Filters. - Derham's Filter Bag. - Derham's Pressure Fil-ter. - English High Pressure Filter. - English Hydrant High Pressure Fil-ter. - Gaber's Sandstone Filter. - Natural Stone Filters. - Asbestos Filters. - Cistern Filter. - Double Cistern Filter. - Low Pressure Cistern Filter. - Rawling's Patent Filter. - Settling Tank with Sediment Separator. - Self-acting Cistern Filter. - Slate Cistern. - Domestic Filter. - Rain-Water Fil-ter. - Clapp's Home-made Filter. - Bowker's Charcoal Filter. - Other Home-made Filters. - Plastic Coal Filter.

A Specific Knowledge Desired

Many are the devices and systems put forward for the purpose of filtering and purifying water, and great is the desire among mankind in general for a system of filtration or a filter which will prove desirable and " fill a long-felt want". All specific contrivances, we take it, will fail, for the reason that as everything needs more or less cleansing, so also, only more so, do even the best of both systems and filters need cleansing and attending to. A person's face will not long remain clean even with atmospheric contact only. How much filthier must a filter become which is supposed to catch and absorb all the impurities contained in most waters; and how great the need of most frequent cleansing if good water is desired. With these few remarks thrown in, by the way of introduction, we will pass on to notice the different systems and filters which have come to our notice and are deemed worthy of mention here.