Stephen Gray

Stephen Gray (1666 to 1736) was an English dyer and astronomer who was the first to systematically experiment with electrical conduction. Born in Canterbury, Kent, he was apprenticed in the cloth-dyeing trade but educated himself in natural science, ground his own lenses, built a telescope and made minor discoveries about sunspots. He helped John Flamsteed with observations and calculations for the star-map being prepared at the Royal Greenwich Observatory, and later worked in London with John Theophilus Desaguliers. Before his work in 1729 the emphasis had been on generating static charges and studying static phenomena such as electric shocks and glows; Gray showed that electricity can be conducted through metals and that it appeared on the surfaces of insulators.