From Phil Eaton
I read the “Why your brain flips over visual illusions” article (4 September, p 14), then the piece “Weird water lurks inside giant planets” (4 September, p 15), only to find that the diagram of a planet’s interior exhibited just the kind of perceptual visual switch discussed on the previous page. Sometimes the cutaway section appeared to be a pyramid protruding from the planet, and sometimes it appeared to be concave as intended. What a coincidental juxtaposition.
Burton on Trent, Staffordshire, UK
