There seems to be no visible mechanism, leading one to believe that it must be a matter of charging the runes to operate the valves themselves. Whether they will still be functional given the great split in the ceiling is uncertain. However, if the amount of moisture (and fungus and green moss and other gently phosphorescent growing things blanketing the arch and its hanging vessels) is any indication, it's likely that whatever cistern waits above has been leaking down into this place because of it.

A further skittering in the darkness and a tremble of the webs strung about the cavern is the last warning. With a spitting, venomous hiss, a number of giant spiders come clambering out of the darkness toward the sound of Tony's raised voice.