A system is disclosed wherein white waters, i.e., those soapy waters coming from washing stands, showers, wash basins and the like, are carried, through receiving and filtering devices, down to the tank or container of a toilet either at the same level of the building or down to a lower level. By means...http://www.google.es/patents/US4069521?utm_source=gb-gplus-sharePatente US4069521 - System and means for using white waters in buildings
System and means for using white waters in buildings
