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The mermaid in the fishbowl: the rise of optical illusions and magical effects

The nineteenth century saw the publication of several books explaining how magical effects and spectral appearances could be performed using the science of optics. It started in 1831, when Sir David Brewster (famed for his discovery of Brewster polarization and inventing the kaleidoscope) published Letters on Natural Magic. In this book, Brewster showed how to produce images of ghosts using partially silvered mirrors and by using a magic lantern to project images onto screens or onto clouds of vapor.

Brewster’s work inspired generations of stage magicians including Henry Dircks and John Henry Pepper, who eventually patented what came to be called the “Pepper’s Ghost” illusion. Pepper’s Ghost, impressive as it was, barely scratched the surface of what was possible using optical engineering. It’s a little surprising that more sophisticated optical tricks did not appear until the twentieth century, considering that the rules of imaging had been derived well over two hundred years earlier. But in 1909 something new and impressive burst forth in its fully formed glory. Antoine Francois Sallé, an engineer living in Paris, was granted a United States patent on a “Means for Producing Theatrical Effects” (US 922,722).

Pepper’s Ghost, via Wikimedia Commons

Sallé’s holographic invention

Sallé’s invention used the Newtonian rules of imaging, which hold both for lenses and for curved mirrors. Under the correct circumstances, one can create a “real” image (through which light rays pass, as opposed to a “virtual” image, which light rays do not pass through; if you place a screen where a real image is located, it will show up on the screen—a virtual image will not) that is the same size as the object, or magnified, or reduced, depending upon the relative positions of the lens or mirror, the object, and the focal length of the optic. The image will, however, be upside-down, but this can be corrected with an image inverter.

“an image produced using a curved mirror can look much more convincingly real, and over a larger range of angles, than an image produced by a lens.”

Using mirrors has advantages over using lenses to work this trick. There is no separation of colors as with a simple lens. In addition, a curved mirror can be used to cover a larger angular region, letting the image be viewed farther off-axis than can be seen with a lens, unless a very large and expensive lens is used. The result is that an image produced using a curved mirror can look much more convincingly real, and over a larger range of angles, than an image produced by a lens. With a subject that is brightly illuminated, the result was that a viewer on the other side of the apparatus saw a perfect reduced image of the subject. If the subject was a person, it could walk around and interact with things. Moreover, the image appeared to be three-dimensional, since each eye of the observer saw the image from a slightly different angle that provided a stereoscopic effect. The word wasn’t yet being used in this context, but a later generation would describe such images as holographic—perfect miniature 3D images of a moving person.

Sallé licensed his invention throughout Europe, and it was displayed in a number of places, including the Crystal Palace in London, the Werkbund Exhibition in Cologne, Germany, and the 1914 Jubilee Exposition in Norway. It was also exhibited in a limited way in the United States at the Steel Pier in Atlantic City and at the St. Francis Hotel in San Francisco, but the image’s bigger splash in the United States was yet to come.

Tanagra Theater reaches the United States

In 1922, the German Edward B. Schreyer bought the North American rights to Sallé’s patent, moved to the United States, and set up the Tanagra Theater Company at 229 West 42nd Street, in the heart of New York’s Theater District.

Schreyer arranged for a Miniature Fashion Show at the 71st regiment Armory, featuring miniaturized models wearing the latest clothes from the Bijou Dress company of Fifth Avenue. Meanwhile, the illusion was also on display at Coney Island, New York. A behind-the-scenes description (which wasn’t quite accurate) of how it worked was published in Huge Gernsbach’s popular technology magazine Science and Invention.

At about the same time, a production of Karel Čapek’s science fiction play R.U.R. (Rossum’s Universal Robots) was staged in Berlin and Vienna with sets designed by Frederick Keisler, who had seen the effect at the Werkbund Exhibition eight years earlier and incorporated it into the design for the show. Sallé’s effect, now called Tanagra Theater (because the miniature images resembled the tiny figurines that had been unearthed in Tanagra in Greece), had finally made the big time.

The wide use of the Tanagra Theater illusion for advertising and for displays in front of small groups of people is due to the technical limitations of the illusion. Although it provides a perfect miniature illusion, this can only be viewed over a small range of angles, which are limited by the size of the mirror. If you can’t see the mirror, then you can’t see the image.

Tanagra Theater is inherently made for small, close-packed audiences. You can have a situation where you limit the viewing time of your audience and keep moving them through so that everyone gets a view, paying for a necessarily time-limited seat. Or you can use it for advertising, luring viewers in with the promise of seeing something interesting, but which repeats the same things after a short period so that you get high turnover. Tanagra Theater was limited to short ads or to peep show experiences. Kiesler’s use of it in a stage show has to be seen as a stunt, since most of the audience would have been unable to see the miniature image at all.

Peep shows and nude exhibitions

Patents at the time only had a twenty-year lifespan. By 1928, Sallé’s original patent had expired and anyone was free to use the invention without having to pay royalties. Not surprisingly, the field opened up, with many people exploiting the liberated technology. Anthony “Tony” Sarg was already famous as a puppeteer, children’s book artist, and producer of unusual artworks. He is credited with reviving interest in puppets and marionettes. His huge inflatable sculptures were a hit at his Cape Cod studio, and he eventually filled them with helium, effectively creating the Macy’s Thanksgiving Parade. Possibly because of his love of puppetry, he experimented with the Tanagra Theater. He installed a Tanagra Theater in the display window at Filene’s Department store in downtown Boston. Like Schreyer’s Tanagra Theater, it was used for miniature fashion shows.

“The Car in the Clouds [was] an advertisement for the Ford Motor company that featured a miniature woman in a miniature latest-model Ford car that appeared to be flying over a landscape”

Later he created The Car in the Clouds, an advertisement for the Ford Motor company that featured a miniature woman in a miniature latest-model Ford car that appeared to be flying over a landscape. There was a microphone hidden in the steering wheel that connected to speakers outside, so the woman could hear questions from viewers and reply. The Car in the Clouds showed up at the Ford pavilion at the 1933 Century of Progress Exposition in Chicago, the 1937 Great Lakes Expo in Cleveland, and at the Steel Pier in Atlantic City (where there was a long-running automobile display).

Image of The Car in the Clouds illusion from The Coast Star, 8 May 1936

Others discovered the extremely powerful draw of sex and started exhibiting miniature nude women using the Tanagra apparatus. In 1931, the 365 Club in San Francisco (later Bimbo’s 365 Club) began showing Dolphina, the mermaid at their bar. Dolphina didn’t have a fish tail, but she was naked. Being reduced to fantasy size and clearly untouchable probably helped keep the show from being shut down, but this was the golden age of burlesque and the Depression, and public mores had loosened somewhat—Sally Rand’s Bubble Dance and Fan Dance were the hit of the 1933 Exposition. Dolphina still appears at Bimbo’s today.

Naturally, there were imitators. Billy Rose’s Casino de Paree in New York featured its own nude mermaid. When that nightclub shut down after a very short life, other nightclubs in New York started featuring them. There appears to have been a Fishbowl Mermaid at the 1933 Exposition, as well. The 1937 Great Lakes Exposition featured a “Little French Nudist Colony” that lived up to its name, literally.

A traveling show called the “French Follies” or the “Parisian Spices” toured the United States. As an enticement, they featured a Mermaid in a Bowl in the theater lobby. This might not always have been a nude mermaid, but the one displayed in Washington, D.C. in 1935 apparently was. The Daughters of the American Revolution took offence and protested to the theater owners. They responded by putting a “strawberry colored” bathing suit on the mermaid.

The Fishbowl Mermaid

A Miniature Mermaid display, compact and transportable enough to be displayed in a theater lobby, sounds like something that wouldn’t work with the full Tanagra Theater. It might work with Bostock’s negative lens, but it’s likely that it was around this time a third major method of producing the illusion debuted. This is likely the same one that later ended up being used by traveling carnivals. It’s very simple and uses very inexpensive and easy-to-obtain components, rather than expensive and hard-to-fabricate curved mirrors or large lenses.

The fishbowl in which the mermaid appears is also the optical element responsible for the illusion (see diagram below). The bowl is filled with water. Better still, it is filled with clear mineral oil, which won’t let algae grow in it and won’t evaporate. This fluid-filled spherical bowl acts like a lens. It’s not a perfect lens, because it doesn’t have constant power across its face and has lots of chromatic aberration. But that’s okay, because it does make the mermaid appear to be truly underwater. The bowl sits atop a large rectangular box. There’s a large mirror behind the bowl, angled downward at 45 degrees, directing up light rays from inside the box.

Author’s diagram of the Mermaid in the Fishbowl illusion

Inside the box is a woman dressed as a mermaid, and maybe some undersea props. Her image is upside-down, but that’s not a big deal—she’s lying down and can lie with her feet in either direction, but appears to be upright. Her image is actually projected forward beyond the fishbowl, but most customers won’t notice—her image is a line with the fishbowl, so she appears to be in it. If you want to make the illusion perfect, put a second fishbowl in front of the first one, into which her image is projected (amazingly, this innovation isn’t documented until it showed up in a 1978 patent).

“The Fishbowl Mermaid became a fixture of traveling carnivals and freak shows.”

The proliferation of nude illusions bothered one entrepreneur who had worked at Billy Rose’ nightclub and had seen the nudes in 1933. Mike Todd felt that this use limited the potential audience. Children were the ideal targets for this technology, and he proposed using Santa Claus as the miniaturized subject (wasn’t he, according to Clement Clark Moore, “a right tiny old elf” with “eight tiny reindeer”? How else could he slip down chimneys?). This individual re-invented Bostock’s device, using war-surplus lenses bought for pennies on the dollar. Like the woman in The Car in the Clouds advert, he could speak to the audience using a telephone on a stand at his side. It was granted a patent and licensed to major department stores at Christmas in the big cities and made a small fortune for its creator. He was later to become a film producer and the driving force behind the Todd-AO widescreen process.

Interest in the illusion fell off after the second World War. The novelty was gone. The Girl in the Fishbowl still showed up at Bimbo’s and a few other nightclubs as an eccentricity. The Fishbowl Mermaid became a fixture of traveling carnivals and freak shows. Carnival operators could learn how to build one from the plans in “Brill’s Bible”, the mail-order guide for carnies.

Ultimately, the Tanagra Theater illusion suffered from its inability to play to a large enough audience to justify its expense. In many ways, Tanagra Theater resembles a much later optical effect—3D holographic movies. Such movies exist and are restricted to small sizes (being limited by the size of the holographic film) and small audience size, and limited range. Holographic movies, like Tanagra Theater, produce amazing 3D images, but they are expensive to make, have limited interest, and can only play to a small “house”. Both technologies, unable to pay their own way, have been reduced to the status of curiosities.

Featured image via Wikimedia Commons

Recent Comments

  1. Denise Mead

    Amazing how clever the illusion of each
    Amazing illusions still puzzle us .

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