It was long ago noticed that if a sample of amber is rubbed with cloth, the amber became endowed with certain apparently wonderful properties. For example, the amber would be able to attract small par...It was long ago noticed that if a sample of amber is rubbed with cloth, the amber became endowed with certain apparently wonderful properties. For example, the amber would be able to attract small particles of fluff to itself. The effect is called the triboelectric effect. The amber, after having been rubbed with cloth, is said to bear an electric charge, and space in the vicinity of the charged amber within which the amber can exert its attractive properties is called an electric field.