Engineering & Theater Infrastructure: “They Say the Neon Lights Are Bright…”

by Michael N. Geselowitz, Ph.D., Senior Director IEEE History Center
June 2, 2022

After an extended hiatus due to COVID-19, Broadway is finally reopened and gearing up for an exciting spring season with a variety of new and returning productions filling theaters. The revitalization of the bright neon lights on Broadway reminds us of the tightly knitted connection between theater infrastructure and electrical engineering.

Even before the current age of smoke machines, strobe lights, and other high-tech special effects, live theater faced a challenge if it was held indoors away from the elements: how could it be lit in such a way that the action would appear somehow “natural”, and yet could be seen by an audience who were not at the natural distances and angles from the actors they would have been if they were part of the action in real life.

As early as 1585, the Teatro Olimpico (“Olympic Theater”) in Vicenza, Italy, was lit by candles. Candles in theaters were eventually replaced by oil lamps and then by gas lights. None of these technologies, however, were sufficient to produce “specific illumination” that provides a sharp, highly controlled shaft of light. These shafts are used to highlight a small area of the stage or create the illusion of moonlight or sunlight. The problem was solved in 1816 with the invention of the limelight by civil engineer Thomas Drummond. Drummond directed a hot hydrogen fire at a cylinder of calcium oxide, known as quicklime. Quicklime has a high melting point and gives off intense light when heated. He developed the technology for surveying, but its theater application soon became obvious. The first theater to use limelight for indoor stage illumination was Covent Garden in London in 1837. The chemical nature of the lamp, however, led to problems with safety and comfort.

In 1807, British chemist and inventor Sir Humphrey Davy demonstrated the carbon arc lamp, but its utility was limited by the available power sources (batteries made of voltaic cells). By the 1890s, inventor Charles Brush, and others, had developed generator-powered carbon arc lamps which began to replace limelight in theaters. By the 1920s, the incandescent lamp of Thomas Edison was able to achieve 1000-watt status, and that new technology began to replace arc lamps, while limelight disappeared altogether. (The term, though lives on…to this day people still talk about an egotist “hogging the limelight”!!).

Meanwhile, incandescent technology enabled inventor Louis Hartmann to build the first follow spot in 1904, a powerful stage light concentrated by a lens that can be controlled by a human operator to “follow” actors around the stage (which is now more commonly known as a spotlight). David Belasco, a pioneering Broadway writer, director, and producer, first used it in the Broadway production of “The Music Teacher.” A number of advances based on lens technology followed, most notably those by the Kliegl brothers (inventors of the eponymous klieg light, used in cinema and at rock concerts).

David Belasco designing a set with the Heads of His Artistic and Mechanical Departments, (photograph originally published in “The Theatre Through its Stage Door”, written by David Belasco, and published in 1919.)
David Belasco designing a set with the heads of his Artistic and Mechanical Departments. (Photograph originally published in “The Theatre Through its Stage Door”, written by David Belasco, and published in 1919.)

The flexibility provided by electric lighting to both general and specific illumination has enabled the modern theatrical experience – from the barest one-person play to a Disney extravaganza. There may be no business like show business, but there is no profession that enhances quality of life like the electrical engineering profession!

Check out our REACH Electric Lighting inquiry unit to learn more about the connections between the invention, commercialization, and adoption of electric lighting and other kinds of artificial illumination in the late nineteenth and early twentieth centuries.

A version of this article was originally published in IEEE-USA Insight.

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