Clarke's magneto-electric machine, 19th century.
© Science Museum / Science & Society Picture Library
In principle, this machine is the same as the machine invented by J Saxton, the only significant difference being in the composition of the magnet itself. E M Clarke's machine in this form requires a source of electric current to energize the electromagnet. Clarke invented the machine in 1835, and J Newman manufactured it bewteen 1836 and 1837.