The Museum of Science is home to the world's largest air-insulated Van de Graaff generator. The generator was generously donated to the Museum by the Massachusetts Institute of Technology. Designed and built by Dr. Robert J. Van de Graaff, who was a professor at MIT, this generator was originally used as a research tool in early atom-smashing and high energy X-ray experiments. As newer methods of atomic acceleration became available, the machine was used for instructional purposes only. Finally, it was donated to the Museum, where it now stands on public display in the center of the Thomson Theatre of Electricity and is demonstrated daily.










This is an early Van de Graaff generator being demonstrated by Robert J. Van de Graaff, himself.





Here is the engineer's prototype of the generator being demonstrated by Dr. Van de Graaff at the Hotel Statler. It stood approximately six feet tall and was capable of producing about one million volts of static electricity.




Finally, in 1931, the large Van de Graaff generator was constructed in an unused dirigible dock at Round Hill, the estate of Colonel E.H.R. Green, in South Dartmouth, Massachusetts.






The Van de Graaff was constructed on railroad track bases, so that it could be wheeled out of and within the hangar.






A laboratory was set up in each of the two domes. Here, scientists could study the effects of 5 million volts of electricity as it struck the target in the tube that ran between the domes.

The colossal Van de Graaff was dismantled and brought to the Cambridge campus of MIT.











Here, it was reconstructed and a large metal building was erected around it.

In the early 1950's, the giant Van de Graaff generator was donated to the Museum of Science. For years, it was enclosed in a small steel structure on the Museum's property, where it was occasionally demonstrated. Finally, in 1980, the Thomson Theatre of Electricity was completed featuring the world's largest air-insulated Van de Graaff generator. Here, the generator is demonstrated at least twice daily, to teach public and school audiences about electricity and lightning.

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