Center of the Hallway                                  -      -      - 
(-------------------------------------------------)     W <---(M)---> E
                                                        -      -      -

The further east you travel you notice that you are less likely to be
able to cast spells successfully.  Several wards have been inscribed into
the walls by someone to insure that, however they lessen in intensity more
towards the west.  You do notice though, that the spells you have on your
armor and accessories are not affected by the preventive magic.