More potable is Aso-take, some 20 m.
- Alcohol intended for potable purposes has always been subject to a heavy duty in all countries.
Apparatus for the economic production of a potable water from sea-water is of vital importance in the equipment of ships.
There are a few fertile spots near the mountains, where mountain streams afford irrigation and potable water, and support small populations, but in general Tacna is occupied for mining purposes only.
Where the strata are not uniformly porous, they may resist the passage of water from the direction of the sea or they may assist it; and round the whole coast of England, in the Magnesian limestone to the northeast, in the Chalk and Greensand to the east and south, and in the New Red Sandstone to the west, the number of wells which have been abandoned as sources of potable supply, owing to the percolation of sea water, is very great.
Purification When surface waters began to be used for potable purposes, some mode of arresting suspended matter, whether living or dead, became necessary.
On account of the small amount of precipitation, the fissured condition of the underlying lava sheets, and the porous soil, the Great Sandy Desert has practically no surface streams even in the wet season, and within its limits no potable waters have been found.