Fire pools are circular pools of water in purgatory, commonly used for scrying and long-distance conversation. They are located in every dormitory in purgatory, typically a yard long in diameter; however, in meditation corridors, an exceptionally large fire pool is used by all of purgatory's priests, and is roughly about one league long.
The water in fire pools directly streams from the river Styx, and scrying is accomplished by communicating with the spirits that inhabit it. In dormitories, they are used by ghosts to find answers to questions to matters regarding purgatory and the process of soul-reaping, which is done by placing a stone tablet, stored with others in front of the pool, on their forehead, asking the respective question and placing the tablet in the water. A column of fire ignites over the water and the question's answer can be read in the flames until they are extinguished. Fire pools are also meant for contacting others, most often Pluto and Persephone for matters that do not require a physical meeting. Ghosts are allowed three uses of their respective pool per day.
The fire pool used by purgatory's priests share the same functions as a normal one, but with the added use of finding humans on the brink of death to sever their threads of life when it is their time to die.