* In 1800, Nicholson and Anthony Carlisle, a surgeon, conducted the first successful electrolysis of water. They used a newly invented voltaic pile (battery) to split water into hydrogen and oxygen. This experiment was a landmark achievement in the understanding of electricity and its effects on chemical compounds.
* Nicholson also contributed to the development of the voltaic pile itself. He experimented with different materials and configurations to improve its efficiency and power output.
* He was a prolific writer and published numerous papers and books on chemistry and other scientific topics. His work helped to advance the understanding of electricity, chemical reactions, and the properties of various substances.
So, while William Nicholson didn't invent a specific device, his work in electrochemistry and his contributions to the development of the voltaic pile were fundamental to the understanding of electricity and its applications in science and technology.