The
Carpenter's Puzzle
Answer :
The
carpenter said that he made a box whose internal
dimensions were
exactly the same as the original block of wood—that is, 3
feet by 1 foot
by 1 foot.
He then placed the carved pillar in this box and filled up
all
the vacant space with a fine, dry sand, which he carefully shook down
until he could get no more into the box.
Then he removed the pillar,
taking great care not to lose any of the sand, which, on being shaken
down alone in the box, filled a space equal to one cubic foot.
This
was,
therefore, the quantity of wood that had been cut away. 
