"Things You Wouldn't Know If We Didn't Blog Intermittently."
I hate to disillusion you, but those are squares.
??? I should have said "squares" instead of "boxes"??
Technically, they are rectangles. Their squareness would have to be verified. True squares have to meet stringent requirements.
Interestingly, if you stand back some distance (will vary) it's no longer an optical illusion. They look exactly as they are drawn--non-touching concentric circles.
That's true - and interesting.