<http://schema.org/description>
"As far back as 1500 B.C.E., people were trying to purify water to make it drinkable. And we&amp;#039;re still at it. Today inventors use tools as simple as clay and as sophisticated as carbon nanotubes to bring clean water to the world."^^<http://www.w3.org/2001/XMLSchema#string>
<http://science.howstuffworks.com/environmental/green-tech/sustainable/10-innovations-water-purification.htm>