Hard water is water that has high mineral content (in contrast with "soft water").
Hard drinking water is generally not harmful to one's health, but can pose serious problems in industrial settings, where water hardness is monitored to avoid costly breakdowns in boilers, cooling towers, and other equipment that handles water. In domestic settings, hard water is often indicated by a lack of suds formation when soap is agitated in water. Wherever water hardness is a concern, water softening is commonly used to reduce hard water's adverse effects.
Read more about Hard Water: Sources of Hardness, Effects of Hard Water, Measurement
Famous quotes containing the words hard and/or water:
“More than illness or death, the American journalist fears standing alone against the whim of his owners or the prejudices of his audience. Deprive William Safire of the insignia of the New York Times, and he would have a hard time selling his truths to a weekly broadsheet in suburban Duluth.”
—Lewis H. Lapham (b. 1935)
“We were uncertain whether the water floated the land, or the land held the water in its bosom. It was such a season, in short, as that in which one of our Concord poets sailed on its stream, and sung its quiet glories.”
—Henry David Thoreau (1817–1862)