The Top of a Geyser                                    -      N      - 
(-------------------------------------------------)     - <---(M)---> E
                                                        -      S      -

The walls of this chamber are rough and rocky, and its curved ceiling
extends quite a ways above you.  However, the odd thing about the room is
that it is almost completely filled with steam.  There are a number of
cracks and fissures in the ground from which the steam seeps forth, but the
main source is a large geyser shooting up in this area.  It issues forth
from a large hole that appears to lead to a chamber below, but the pressure
is too great for you to jump down through the geyser.