This is a parlor sized version of the larger stage version created by the talented craftsman Rocky Clements c. 2009. It is a very clever effect if a little messy to set-up.
While this prop is entirely different in size, appearance, design, and much of the method, it should be noted that the original method was invented by David Howarth c. 1967 called the Ultimate Prediction Slate and manufactured and marketed by Ken Brooke as the Nemo (Prediction) Slate.
Rocky worked on the design and ironed out some issues with the original construction and design and ended up wit the Final Answer.
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