Cube Dovetailing Problem

$\begin{figure}\begin{center}\BoxedEPSF{CubeDovetailingProblem.epsf}\end{center}\end{figure}$

Given the figure on the left (without looking at the solution on the right), determine how to disengage the two slotted Cube halves without cutting, breaking, or distorting.

References

Dudeney, H. E. Amusements in Mathematics. New York: Dover, pp. 145 and 249, 1958.

Ogilvy, C. S. Excursions in Mathematics. New York: Dover, pp. 57, 59, and 143, 1994.