The Question Mark Experiment
Back in 1979, the camera obscura at the Cliff House in San Francisco had been closed for years. Gene Turtle (one of the original builders of the camera in the late 1940s) let ex-carny David Warren run the operation. Along with friends Steve Mobia and Chris DeMonterey, many experiments were tried to encourage people to go inside this unique attraction.
It was observed that many who read the Life Magazine article posted outside would walk away afterward, letting the explanation take the place of the experience.
It was decided that all descriptions of what was inside the building be taken away, with only question marks in their place.
For the few days that this experiment was tried, it seemed to work. The operator in the ticket booth would refuse to explain anything but would merely hold up a sign which read "It's only 50 cents."
Later the name "Giant Camera" was again uncovered but the lengthly explanation was taken away and a question mark was incorporated in the "Now Open" sign. The new sign read "Now Open, What is It?"
This old super 8 film dates from 1979