In 1800, English chemist William Nicholson was the first to produce a chemical reaction by electricity. He had been working with Anthony Carlisle, a London surgeon, experimenting with Allesandro Volta's voltaic pile. The new effect was discovered when wires from the poles of the battery being used came into contact with water and bubbles of gas were released as current flowed through the water. Closer examination of the electrolysis showed oxygen was released at the (positive) anode, and hydrogen appeared at the cathode. Electricity had separated the molecules of water. Further, the effect of the amount of hydrogen and oxygen set free by the current was proportional to the amount of current used