p. 382 | Home-Made Filters

International Tract and Missionary Society · Oakland, Cal. · Jun 18, 1885

FromSigns of the Times, Vol. 11, No. 24.

Home-Made Filters.

THERE are various forms of house filters, some of which are cheap and valuable. Flannel tied on the faucet of the water pipe will greatly improve the appearance of drinking water, and will strain out much organic matter. A tube or box with sponge in it will also be satisfactory in clarifying turbid water, and it is easily and quickly washed and replaced. A sheet of filtering paper as used by druggists, and a glass or tin funnel, furnishes a good means of filtering water on a small scale. A fresh sheet of filtering paper will be generally needed each day. Granulated animal charcoal, in boxes or vessels where the water can filter slowly through it, improves its appearance and quality. The chief idea of a filter is well illustrated thus:—

Take any common vessel perforated below, such as a flowerpot, and put a small, clean piece of sponge over the hole. Fill the lower portion with gravel stones, over which place a layer of fine gravel and on these a layer of clean, coarse sand, the proportion of each being about the same.

On the top of this place a lid of unglazed clay, either very porous or perforated with small holes, and on this a stratum three or four inches thick of well-burned, pounded animal charcoal. A filter thus formed will last for a long time, is easily cleaned, and will be found to act both by mechanical and chemical purification.

Another form of filtering, as suggested in the last report of the State geologist, is as follows:—

“The most practical form of filter for household use, and one that will easily filter a pitcher full of water in a short space of time, can be made out of a bottle. The best form is the long kind in which sweet oil is sold, although almost any kind of glass or earthenware bottle will answer. The bottom of the bottle is cracked off, and the sharp edge removed by rasping with a file. The cracking can be done by taking a thin, soft string, soaked in turpentine, around the place where it is intended to crack, leaving as small a knot as possible, then setting fire to the turpentine, holding the bottom up. After allowing the oil to burn for an instant, the end of the bottle is placed quickly in cold water, when, if the operation has been rightly conducted, an even crack will be produced, and the bottom of the bottle will come off easily.

“A layer of cotton is now placed in the bottle. The cotton must be worked in water, preferably warm water, in order to remove the adhering air, and to wet it well. A wad of the wet cotton is dropped into the bottle and covers the mouth of the neck. Other pieces are dropped in, care being taken to build the layer up evenly, and to add the cotton in rather small pieces. After dropping them in, they should be pressed down and arranged by means of a rod. In this way a layer is made that should be from two to three inches thick. It should not be pressed down too tightly, else it may filter too slowly; neither should it be too light, or water may form channels through it. After a little use the plug generally adapts itself. Particular care should be taken to be sure that the cotton is snug against both sides, since the water is liable to escape there. The plugs, however, are easy to make, and a few attempts will soon teach one all the necessary manipulations.

“This bottle can be suspended or supported in any convenient way. Perhaps the simplest support is a block of wood having an auger hole bored through the center, and the edges of the hole reamed out. In this hole the bottle sits securely, and the bevel of the hole catches the shoulder of the bottle, thus holding it upright.”—Sel.