octagons
As a scientist Hankin describes very systematically the decorative patterns he sees, from very easy ones to very complex ones. A very simple application of the 'Polygons in contact' is the fitting of octagons.
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Hankin understands that one can start from this basic pattern to create some more complex patterns. In the octagons two diagonals are drawn, so that above the octagons a pattern is created that, on first sight, hasn’t got anything in common with the regular octagons.