Theater of Electricity

The Museum of Science opened its first building at Science Park on March 12, 1951. The administration had plans to include many features, including exhibits on chemistry, biology, and technology; a planetarium; and a theater of electricity. In the early 1950s, Clarissa Thomson gave $50,000 in honor of her deceased husband Elihu Thomson, a prominent inventor who was one of the founders of General Electric. Thomson, a renowned scientist who had more than 600 patents to his name, contributed many important developments in electrical engineering and technology in the United States, and served as president of MIT in the 1920s. With this gift, the Museum of Science staff envisioned a space with live demonstrations and exhibits about electricity, communications, electromagnetic force, and related technology.

The highlight of this new theater would be a Van de Graaff generator donated by MIT in the 1950s. This immense machine, featuring two enormous metal columns that could conduct 2.5 million volts of electricity, was developed by Dr. Robert Van de Graaff, a physicist who taught at Princeton before being recruited by MIT. In 1931, Dr. Van de Graaff was working on the construction of a large-scale electrostatic generator that could create a much larger voltage than his previous smaller models. Van de Graaff moved his workshop to a waterfront estate called Round Hill, owned by Colonel Edward H.R. Green. Green, an enthusiast of technology and innovation in all forms, had invited MIT to use his estate, which included a radio corporation, broadcast studios, laboratories, and an airship hangar built for dirigibles. The addition of a large electrostatic machine only added to the variety of experiments occurring on the Green Family estate. Colonel Green and his family, particularly his mother Hetty Green, have a colorful history that is worth investigating.

Dr. Van de Graaff used the huge empty airship hangar to construct an extra-large version of his generator. At any size, conveyor belts carry electric charges up to the aluminum domes, where sparks are created. Completed in 1932, the finished steel towers of the large-scale generator stood at about 40 feet high, and could produce millions of volts of electrical energy by using moving belts to accumulate electrical charges. This energy was used to accelerate atomic particles as part of physics research. By the 1940s, the large Van de Graaff generator was outdated as researchers switched to other, more powerful particle accelerators such as cyclotrons. MIT offered the massive generator to the young Museum of Science, who were in the process of designing their new campus at Science Park.

The Museum already had a small Van de Graaff generator on display in its temporary structure, donated by the High Voltage Engineering Corporation, and educators were excited to showcase the much-larger version to visitors. But first, significant fundraising was needed to construct the Theater of Electricity; in 1955, a campaign to raise $2.5 million to construct several structures at Science Park, including a theater be named after Elihu Thomson. In 1956, the generator was moved to Science Park and stored in a temporary outbuilding at the edge of the parking lot. Although the generators were not used for public displays at this point, other electrical demonstrations were given with small Tesla coils and other implements around the foot of the generator, separated from visitors by only a wooden railing.

The Elihu Thomson Theater of Electricity would remain a separate structure until the summer of 1978, when funds were raised to finally develop its Hall of Energy, which would encompass the Van de Graaff generator. This construction was aided by additional gifts from Clarissa Thomson, who willed the Museum $1 million as an endowment in 1963. The Museum tapped E. Verner Johnson, the architect of the West Wing and the parking garage, to design this new building, with three stories of exhibits and viewers arranged around the enormous generator.

An enormous Faraday cage was constructed of vertical wires to protect viewers by containing stray electrical charges emanating from the 15-foot aluminum spheres of the Van de Graaff generator. Similar to today, an educator used a console at the front of the exhibit space to operate the generator and other, smaller equipment. Multiple Tesla coils, modeled on the original device designed by Nikola Tesla in 1891, are used by educators to demonstrate high voltage in sync with the large generator. Other exhibits in this new building included a display of inventions by Elihu Thomson, a solar greenhouse, and other examples of electromagnetic and physics equipment.

Known today as the T.O.E., the Theater of Electricity is a beloved icon of Science Park, representing the Museum’s ability to entertain while educating its visitors. Free demonstrations multiple times per day allow visitors to experience the awe of this indoor lightning machine, while learning about the mechanics (and dangers) of electricity. Every presentation is different, unique to the educator providing the demonstrations, but always guaranteed to excited visitors of all ages.