THE FOUR SHAM PILLARS

In 1689 the architect Sir Christopher Wren designed the interior of Windsor Town Hall near London. He built a ceiling supported by pillars. After city fathers had inspected the finished building, they decided the ceiling would not stay up, and so they ordered Wren to put in some more pillars.

England's greatest architect didn't think the ceiling needed any more support, so he pulled a fast one. He added four pillars that did not do anything; in fact, they don't even reach the ceiling.

The optical illusion fooled the municipal authorities, and today the four sham pillars amuse many a tourist.