A lava lamp contains wax, water and a light which acts as heating element. As the lamp gets warm, the wax melts and starts to rise. As it rises it forms interesting shapes, which makes lava lamps fun to watch. Lava lamps come in all sorts of different colors, and the wax and water in them also come in different colors.
Lis forLazy Susan
A lens is a device that changes the way light bends. When you look through a lens things look different to when you don't look through the lens.
Lenses can be used to make things seem closer than they are, or in spectacles to correct poor vision.