The pillars support a balcony in the auditorium of the school. The school and auditorium are still in use and when we arrived they were in the middle of a graduation ceremony. When we returned later that day we had a chance to freely look around and take pictures of the pillars.
|The 3 pillars in the Johanna Westerman School|
The tiles were made by "De Porceleyne Fles", a tile and ceramics company from Delft. The three designs were carefully chosen by Escher to be educational.
The front column has rotational symmetry: consider the white lizard and give it a half-turn around the point defined by his nose. The lizard will then align perfectly with the other white lizard. The design consisting of lizards is based on regular division print 104 as shown in Schattschneider's Visions of Symmetry.
The pillar can be tiled with just one type of tile in this case. Each tile consists of one while lizard and the rest of the tile is black. A half-turn on alternate tiles then creates the pattern we see. The black segments carefully match up to create the image of the black lizards.
The second column is based on regular division print 74 and from the point of view of symmetries is the simplest of the three. The design only has translational symmetries. We can slide one image on top of another, but no other motions will cause the separate images to align themselves.
Here again only one tile is used. In this case the tile does not contain a full image of a bird, but instead is carefully designed to create images of black and while birds when columns of tiles are placed with a vertical shift allowing the heads of the birds to align with their bodies.
The last column is based on print 96 and has glide reflectional symmetries. If you take the image of a black swan and shift it up half a tile length and then flip it over a vertical line, it will align itself with the white swan.
One tile is used to cover the pillar and create a pattern where white swans fly to the right, while black swans fly to the left.
[Thanks to my sister for her company, support and for several of these photographs.]
1. Schattschneider, Doris  (2004). Visions of Symmetry - Notebooks, Periodic Drawings, and Related Work of M. C. Escher, 2nd, Harry N. Abrams. ISBN 0810943085.