A home-made filter, which appeared in the National Bottlers' Gazette, is given in the accompanying illustration. Such filtrant can be used as suits the idea of the bottler constructing it; but as this filter is composed of the simplest materials - sand and charcoal - no trouble will be experienced in securing them. The filter is arranged from a 50-gallon wine cask with a false bottom, perforated; on this a layer of gravel, then alternate layers of charcoal and white, clean sand, and top layer of excelsior, with perforated cover ten inches from the top, and a discharge-pipe or over-flow four inches from the top. A cross-bar of wood, four inches square, is held across the head of the barrel, through the centre of which a common wooden headed screw held the filter in solid mass. A discharge-cock in the bottom of the barrel, when opened, carries off the sediment, and the closing of the feed-pipe allows the filter to clear itself. Instead of excelsior shown in illustration coarse gravel may be substituted, and if the inside of the barrel and the perforated cover be charred, this would be an improvement and exercise a preserving action on both filter and water. The same but plainer style of home-made filter with descending current may be made after the following directions: Take a tub, a barrel or a wooden tank with an open top; put into it a perforated false bottom so arranged that there is a space of about two to three inches or more between the two bottoms and bore a hole in the bottom or side beneath the false bottom, for a wooden or iron faucet with which to draw off the purified water. Place a felt, flannel or other suitable substance over the perforated false bottom, being sure to fill out the sides well, so as not to permit any coal to escape there, or elsewhere, and put into the tank a quantity of bone-charcoal, filling it about one-half full or a little over; it is then ready for use. A very similar style of filter is made by Dr. H. L. Bowker & Co. in Boston, and illustrated in this cut.

Fig. 39.   Clapp's Home Made Filter

Fig. 39. - Clapp's Home-Made Filter.