ARE THESE LINES PARALLEL?

The “herring-bone” figure here illustrated is yet another proof that

our eyes are faulty. The horizontal lines appear to slant in the

direction in which the short intersecting lines are falling, and

would give one the idea that they would meet if continued, whereas

really they are parallel. The illusion is more striking if you tilt

the leaf up.

[Illustration]

The puzzle king · 第 109 / 216 题