A Practical Manual On Sea Water Distillation
With A Description Of The Necessary Machinery For The Process

i5o CHAPTER VIII. (a) THE FILTER; (6) THE STEAM PUMP; (c) THE CONNECTIONS; (c?) SPARE GEAR; (e) CLEAN- ING- ARRANGEMENTS; (/) BOARD OF TRADE RULES. (a) The Filter. 1. The filter is an important item where distilled water of the best quality for drinking is required. A water may be pure, yet unpalatable. The mawkish and insipid taste of distilled water is too well known to need description. This insipidity is entirely removable by proper aeration and filtration of the distilled water. 2. Animal charcoal is used for rendering (aerated) dis- tilled water palatable, but to be effective its relative volume must be large. 3. Distilling apparatus for producing drinking water should include a filter. It adds rather to the bulk of the plant, but on land the apparatus may be made more capacious than that for a steam ship. 4. For the filter to be effective the distilled water should be well aerated—that is, well impregnated with air. When any water is heated the air in solution is driven off long before it boils. This may be seen by putting a little ordinary cold water in a test tube, and holding the tube over a gas flame. In a moment or two small bubbles will be seen adhering to the sides of the