Electrostatic Force
Electricity and Magnetism

Martinus van Marum’s machine

Stories from Physics for 11-14 14-16 IOP RESOURCES

Martinus van Marum, a Dutch physician, developed an interest in the physical sciences and was appointed director and curator of the cabinet of curiosities of the Dutch Society of Science. Van Marum gave public demonstrations of chemical and electrical phenomena and, in the 1780s, had a large static generator built which can be seen today in the Teylers Museum in Haarlem.

The machine consists of two glass discs, 1.5 m in diameter, that can generate a potential of 300-500 kV and produce sparks over distances of 7 m. The effects of the machine on different objects were impressive: a 10 cm by 10 cm piece of box-wood was “rent in pieces”, metal objects were melted and “dispersed in all directions” and a piece of tin was vaporised.

Van Marum developed other demonstrations of static electrical effects, including artificial clouds formed of two bladders filled with hydrogen gas and given opposite charges. The bladders gradually rose to the ceiling, were attracted to each other, and, when they were close enough, a spark jumped between them causing an explosion. To make the demonstration more like a storm, Van Marum added a third balloon, filled with a mixture of hydrogen and air, between the two balloons. This exploded with a loud bang when the artificial lightning was triggered.

References

IOP DOMAINS Physics CPD programme

Energy CPD videos

Our new set of videos gives teachers and coaches of physics a preview of the training we offer ahead of this term's live support sessions.

Find out more