FILTRATION EXPERIMENTS AT LOUISVILLE, KY.

FILTRATION EXPERIMENTS AT LOUISVILLE, KY.

Experiments in filtration have been going on at Louisville, Ky., for nearly a year, with a view to rendering the water of the Ohio wholesome and potable. Chemists areengaged on the report, figuring upon the cost of operation as well as the results of microscopic and bacteriological examinations and other chemical tests. Of the systems being tried three are alike in the general principle of the employment of a chemical coagulant to precipitate the impurities and a mechanical filter of sand, through which the water is passed after the process of coagulation. The process is completed by the passage of the water through a bed of sand, the flakes of hydrate being left sacking in the small interstices between the tiny particles of quartz or other mineral of which the sand is composed.

Another plant consists essentially of tanks, in which two or more electrodes connected with dynamo wires are placed in water in a magnetic field. This magnetic field is made by the pole pieces (which are enameled by way of electric insulation) of the magnet projecting into the water. The induction capacity of water being seventy-six times as much as that of dr)’ air, the action of the electrodes is enhanced by the magnetic field so constituted. From this follows an electrolysis, by which the impurities of the water, whether in solution or in suspension, are thrown into an insoluble condition. The water is thus brought to a consistency analogous to that aimed at by the use of the chemical coagulants in other systems, and is ready to be passed through a system of funnels and filters, by which the solid matter is separated out. In the course of the electrolysis there is a considerable liberation of gases, principally nascent, oxygen, and hydrogen, which may be easily ignited with a match.