Capitol Reflections - Glenna Bayer pictured the Capitol, Washington, D.C. reflected by the aptly named Capitol Reflecting Pool. The Ulysses S. Grant Memorial is the statue silhouetted by the floodlit building.  Images ©Glenna Bayer, shown with permission.

The overall Daliesque pattern is recognisably the inverted Capitol dome. The detail is stranger. The stacked pancakes sometimes alternate thin and fat and sometimes mirror a neighbour. More is happening than simple reflection.  See below...

                                                        Puzzle view

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Many (but not all) Greeks held that we see objects by rays emitted from our eyes.

This is a convenient way to understand what happens when we look at the Capitol's reflection in wavy water.

At left, in the accurately computed ray tracing, a stream of rays leave the eye and impinge on sinusoidal cylindrical waves. The beams are reflected in all directions yet there is order in how they behave.

Imagine that the three parallel green rays point to the distant first tier of columns on the wedding cake of the Capitol dome.

The rays near 'a' point lower and lower as the eye viewing direction is raised. The eye therefore sees an inverted image.

Rays near 'b' are different. They point in the same direction but as the eye viewing direction is raised the building section viewed is also raised. The Capitol image segment is upright.

Point 'c' is like 'a' and gives another inverted image. The surface near 'c' is convex and the image is strongly compressed in the vertical direction.

Each wave gives up to three closely spaced images of the same slice of the Capitol. Two slices are inverted and one upright. The overall reflection is a stack of pancake slices some tossed upside down and some the right way up.

Let the wind move the roughly cylindrical waves in a different direction and the pancakes tilt, twist and contort.