Procure an ordinary lamp chimney and fit two or three thicknesses of cheese cloth over the end of it. Press a tuft of absorbent cotton into the small part of the neck to a depth of about 3 in. Insert the chimney in a hole cut in a wood shelf used as a support. Pour the water in until the filter is filled, when it will be observed that any organic matter, chips of iron rust, etc., will be retained by the cotton. The fine organic matter may penetrate the cotton for about 1 in., but no farther. The resultant filtered water will be clear and pure.