Induction electrostatic machines, like this one designed by James Wimshurst (1832-1903), were developed in the mid 19th century and replaced friction machines for demonstrating electrostatic sparks and other effects. The Wimshurst machine was affected les by atmospheric humidity than most other types. It completely revolutionised the science of static electricity, and its design has not been improved on significantly since. From about 1900 some Wimshurst machines were used to power X-ray tubes, but this was not very common. The principles of electrostatics are now used in photocopiers.
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