Electrostatic machine with sulphur globe, c 1750s.
© Science Museum / Science & Society Picture Library
Engraving by Laplante, of an 'Electric machine with sulphur globe, according to the model in fashion about 1754'. The electrostatic machine produced an electrical charge through the manual rubbing and rotating of a sulphur ball. Some early uses of electricity were medical; it was used to treat paralysis and muscle spasms, and to control heart rates. Illustration from 'Electricity and Magnetism' by Amedee Guillemin (1826-1893), published in London in 1891.