"Underdrain" Quotes from Famous Books
 ... unless the ground water gets up to within three feet of the surface, and, in a number of cases, underdrains have been laid under a sewage filter at considerable expense, only to find when the filter was in operation that they were never in use. In clay soils the underdrain is not necessary. In fact, it may be noticed that the underdrain is not for the purpose of taking care of the sewage, but rather of draining off the soil-water and preventing its interference with the action of ...
— Rural Hygiene • Henry N. Ogden |
