This material is Open Game Content, and is licensed for public use under the terms of the Open Game License v1.0a.
This large container is usually fashioned from blue or green semiprecious stone. It is about 1 foot in diameter, half that deep, and relatively fragile. When the bowl is filled with fresh water, and certain words are spoken, a Large water elemental appears. The summoning words require 1 full round to speak. In all ways the bowl functions as the summon monster VI spell. Only one elemental can be called at a time. A new elemental requires the bowl to be filled with new water, which cannot happen until after the first elemental disappears (is dispelled, dismissed, or slain).
If salt water is used, the elemental is Huge rather than Large (as if summon monster VII had been cast).