This classical
mathematical problem is sometimes called the Delian problem, as it was originally set by the
oracle of
Delios in the 5th Century BC. The Delians were instructed that, in order to rid themselves of a
plague, they must double the
altar of their god -- its shape being a perfect cube.
The problem exercised many mathematicians over the next two and a half millennia, but only in the
19th Century was it proved to be impossible, using the newly-developed mathematical techniques of
group theory.