PURPOSE: To illustrate fluid dynamics in a perhaps surprising way.

DESCRIPTION: The device is preset by filling the upper bottle with water and connecting the air hose between the two bottles by sealing the stoppers. When water is poured into the funnel, it increases the fluid pressure in both bottles by the height of the water from the bottom of the bottle to the top of the funnel. This extra pressure forces water up the tube and out the top of the bottle in a stream which reaches a greater height than that of the water in the funnel. This squirting water keeps the funnel full so the process continues. Raising or lowering either bottle does not effect the height to which the water stream rises above its bottle.

SUGGESTIONS: Shadow projection is available for lecture hall use.

REFERENCES: (PIRA 2B60.10) See Demonstration Reference File for further information.

EQUIPMENT: Two old milk bottles, rubber stoppers with two holes each, connecting tube, squirting tube and funnel, water.


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