In a typical experiment, two 100 mL beakers are filled with deionized water to roughly 3 mm below the edge of the beaker, and the water exposed to 15 kV direct current, with one beaker turning negative, and the other positive. After building up electric charge, the water then spontaneously rises along the thread over the glass walls and forms a "water bridge" between them. When one beaker is slowly pushed away from the other, the structure remains. When the voltage rises to 25 kV, the structure can be pulled apart as far as . If the thread is very short, then the force of the water may be strong enough to push the thread from the positive glass into the negative glass.