The Meniscus

http://www.chem.purdue.edu/gchelp/liquids/tension.html. There is a great flash animation plus description on surface tension. The author of this website explains how the meniscus is formed. It is really interesting how mercury, the only liquid with stronger surface tension than water, forms an upward parabola instead of a downward parabola formed by water. Because the attraction between unlike molecules in water is stronger than the attraction between same molocules in water, they cling on to the glass tube. The meniscus can only occur when the water is placed in a narrow tube. A wider tube will have to much gravity and the water will have to much to lift so it it will be too much to lift.