the first nozzle device 11 which is ejecting water toward the anus is caused to reciprocate the second nozzle device 13 will be caused to reciprocate when the switch 81 is turned on while the switch 67 is on the foregoing functions can be realized by use of a controller 18 in the form of microprocessor referring back to fig3 the regulating device 4 which is designed to regulate or control an amount of water to be supplied to the first nozzle device 11 the second nozzle device 13 includes a body or casing 14 including an inlet passage 14a a first outlet passage 14b a second outlet passage 14c and a third outlet passage 14d the inlet passage 14a is in fluid communication with the water supply 5 in the form a tank not shown within the casing 60 the first outlet passage 14b and the second outlet passage 14c are in fluid communication with the main passage 6 and the auxiliary passage 7 respectively in the extension nozzle 11a of the first nozzle device 11 a motor 17 controlled by the controller is secured to a left side wall of the body 14 of the regulating device 4 and has a shaft 17a which extends into the body 14 within the body 14 a rotating disk 16 is mounted on the shaft 17a of the motor 17 so as to be rotated together with the shaft 17a and is movable along the shaft 17a a spring 19 is interposed between the left side wall of the body 14 and a left side of the rotating disk 16 the.