The Prismic Cylinders
Construction
The construction we used for m,n-duoprisms need not be confined to finite numbers. Consider what happens if we take the limit of these duoprisms as m approaches infinity.

As m increases, the m-gonal prisms in the XY cycle become closer to being cylindrical. The number of members in the ZW cycle start to increase without bound, but their heights decrease toward zero. At the limit, the XY cycle become n cylinders, and the ZW cycle becomes an n-gonal torus. This produces what we call an n-gonal prismic cylinder.

The cubical cylinder is the case where n=4. Here are some other prismic cylinders:

Properties
Although the n-gonal prismic cylinders have n 3D cylindrical surfaces, they can only roll in a single plane. Like the cubical cylinder, which is the same as the tetragonal prismic cylinder, all the circles in the cylindrical surfaces lie in parallel planes, even though the central axes of the cylinders are not parallel to each other. So all of them can only rotate in the same plane, and the n-cylinders can only roll in a single direction, covering only the space of a line.



