Columbia Encyclopedia World Factbook American Heritage Coll. For example, the surface of water in a clean drinking glass is seen to be slightly higher at the edges, where it contacts the glass, than in the middle. Adhesion causes water to wet a glass container and thus causes the water's surface to rise near the container's walls. If there were no forces acting in opposition, the water would creep higher and higher on the walls and eventually overflow the container. In some liquid-solid systems, e.g., mercury and glass or water and polyethylene plastic, the liquid does not wet the solid, and its surface is depressed where it contacts the solid.
Capillarity is one of the causes of the upward flow of water in the soil and in plants.
The Columbia Encyclopedia, Sixth Edition.