Floating over a Bottomless Pit                         -      N      - 
(-------------------------------------------------)     - <---(M)---> -
                                                        -      -      -

The instant you walk over the floor, you set off a trap causing it to
crumble beneath you.  A pit with no visible means of escape lies beneath
you, and above, the entrance to the Tower of Air.  The winds howl and blow
past you, nearly causing you to lose your balance and tumble into the pit. 
Take heed not to drop anything, for you will not be able to retrieve it from
the pit.