PURPOSE: To form a powerful stream with a pump of small capacity by dividing the part of the stream into two stages.

CONSTITUTION: Water for a stream device is supplied by a pump 1. Water supply is performed through a water pipe 2 connected to the pump 1. An acceler ating nozzle 3 is mounted to the end of the water pipe 2. Water supplied and coming out from the accelerating nozzle 3 passes through the part A, and sup plied to the B part from the end part A' and discharged. The A part and the B part are separated by a partition helve 4. While inversely returning through the B part, the water supplied from the A part ultimately returns to the begin ning from the B' part, and sent back to the pump 1 from the inlet port 5 of the pump 1. As a result, a rapid stream can be formed in the same way by a pump of small capacity even in a shallow depth of water.