[ 0017 ] fig1 shows a flushing device 1 , which is connected to a toilet bowl 45 via a pipe elbow 12 . a drain valve 13 , which can be actuated with an actuating means 17 to release an opening 14 in the bottom of the tank 8 , is accommodated in a tank 8 of the flushing device 1 . the actuating means 17 may be a button or a pushbutton or another tripping means . the tank 8 also accommodates an intake valve 4 , which is connected to a water supply pipe 2 . with the intake valve 4 open , the tank 8 is filled with flushing water 50 to a predetermined level . when the drain valve 13 is opened , part of the flushing water 50 flows through the pipe elbow 12 and into a channel 51 of an edge 47 and flows in the direction of the arrows 53 along the inside of a bowl 56 in the downward direction into a u - shaped arch 46 , which forms a trap against a soil pipe 52 . another , substantially smaller part of the flushing water 50 is pressurized with means in the tank 8 , which are described farther below , and it enters , via a pipe 9 , a nozzle 11 , which has a passage 57 into the interior of the arch 46 . this nozzle 11 is directed such that , as is shown in fig1 water flowing in through the nozzle 11 flows in the direction of the arrow 58 into the water 70 present in the arch 46 . the direction of the arrow 58 is also the direction of flow of the water 70 during the flushing process and consequently during the emptying of the trap . a suitable slope angle α can be seen in fig1 . this angle α is , e . g ., approx . 10 degrees and is preferably smaller than 45 degrees . the flushing flow entering through the nozzle 11 has excess pressure , while the flushing water entering the bowl 56 through the channel 51 is only under the action of the force of gravity . the amount of flushing water flowing in through the nozzle 11 during one flushing is preferably substantially smaller than the amount of flushing water released through the channel 51 . the flushing water entering the bowl under excess pressure in the direction of the arrow 58 moves the water 70 in the direction of the arrow 58 and causes the arch 46 to be better cleaned . the excrements present in the arch 46 are carried away and delivered to the soil pipe 52 . flushing water that is under the action of the force of gravity enters the bowl 56 essentially simultaneously with the cleaning of the arch 46 , and it cleans the bowl . the flushing water , subject to gravity and flowing downward into the arch 46 intensifies the movement of the water 70 in the direction of the arrow 58 and refills the arch 46 with water . thus , the two flushing flows cooperate and accelerate the water 70 in order to thus remove excrements from the arch 46 . [ 0019 ] fig2 and 3 show a preferred embodiment of the flushing device 1 . the tank 8 is equipped in the usual manner with a discharge pipe connection 59 arranged in the bottom and with a lid , not shown here . the pipe elbow 12 joins the tank 8 at the pipe connection 59 . the drain valve 13 may be a prior - art float valve , in which a valve pipe 16 is guided in a float housing 60 . the valve pipe 16 can be raised by a ring 19 with a pushbutton 17 pivotable around a support 18 . a valve disk 15 now releases the opening 14 , after which flushing water 50 present in the tank 8 flows through the pipe elbow 12 and into the channel 51 . the drain valve 13 automatically closes after the flushing process in the known manner . in addition , a piston - and - cylinder unit 6 , which consists essentially of two housing parts 33 and 40 and a double piston 61 , is also arranged in the tank 8 . the unit 6 is connected to the intake valve 4 , which is connected at a connection pipe 62 to the water supply pipe 2 . the intake valve 4 is a servo - controlled diaphragm valve . this closes an opening 28 in a passage 29 with a diaphragm 27 in the state shown in fig2 . a passage opening 63 in the diaphragm 27 connects a chamber 29 a of the pipe connection 62 to a chamber 26 of a frame 23 . water , which communicates with the water of the supply pipe 2 through the opening 63 and is under the same pressure , is present in the chamber 26 . since the diaphragm 27 has a larger area against the chamber 26 than against the chamber 29 a , the latter is pressed upward against the valve seat of the opening 28 . the chamber 26 has a passage 25 , which is closed by a valve rod 24 mounted displaceably on the frame 23 in the arrangement shown . a float 21 , which is located in a float housing 20 , is arranged at the lower end of the valve rod 24 . with the flushing tank filled , the float is extensively below the water level marked by the letter a . a valve 22 , which is open when the flushing tank is filled and thus connects the interior of the float housing 20 to its outside , is arranged in the bottom of the float housing 20 . the housing 20 is filled with water and imparts buoyancy to the float 21 , which presses the rod 24 against a valve seat of the passage opening 25 . when the valve pipe 16 is lifted with the pushbutton 17 during a flushing , the water level in the tank 8 drops , and so does the water level in the float vessel 20 at the same time . thus , the buoyancy of the float 21 thus continuously decreases , until it eventually drops down under its own weight , thus releasing the passage opening 25 . water can escape from the chamber 26 to the outside through the passage 25 , as a result of which the pressure in the chamber 26 is immediately reduced . due to the fact that the water pressure in the chamber 29 a is now higher , the diaphragm 27 is moved downward and is lifted off from the opening 28 . the passage from the chamber 29 a to the chamber 29 b is thus open . water can now enter the chamber 5 , which is sealed against an interior space 64 of the housing part 33 with a piston 30 and a circumferential lip seal 31 , from the supply pipe 2 through the passage 29 . the amount of water entering the chamber 5 per unit of time is limited by a flow governor 3 arranged in front of the diaphragm 27 . the flow governor 3 is preferably set such that the water flowing into the chamber 5 has a maximum flow pressure . the piston 30 is connected via a web 32 to a piston 37 arranged farther below it . this piston 37 has a nonreturn valve 36 , which is open in the position shown and connects the interior space 64 to an interior space 65 of the housing part 40 . with the valve 36 closed , the piston 37 seals the interior space 65 against the space 64 with a circumferential lip seal 38 . thus , the two pistons 30 and 37 form a double piston 61 . the space 65 leads via a passage 41 to a nonreturn valve 7 , which has a closing body 42 , which can be lifted off from a valve seat 66 against the reactive force of a compression spring 43 . the nonreturn valve 7 has a connection pipe 44 , to which the pipe 9 leading to the nozzle 11 is connected . when pressurized water flows into the chamber 5 through the opened intake valve 4 , the piston 61 is moved downward by the pressure of this water against the reactive force of a compression spring 39 . the space 65 is filled with water , which is pressurized by the downwardly moving piston 37 and closes the nonreturn valve 36 . the water pressure in the space 65 continuously increases with the piston 37 moving downward , until the nonreturn valve 7 is opened at a defined pressure and water can flow into the pipe 9 through the passage 41 and finally to the nozzle 11 . the piston 37 moves downward , until it reaches an annular surface 67 and a predetermined amount of water is displaced from the space 65 under a predetermined flow pressure . before the piston 37 reaches the surface 67 , the lip seal 31 passes over a plurality of passage holes 34 of the housing 33 . thus , if the piston 37 is in its lower position , water flows out into the flushing tank from the chamber 5 through the passage openings 34 and fills the flushing tank until the water level a is again reached . the water flowing out through the holes 34 is deflected in the downward direction with low noise by a ring 35 arranged on the outside of the housing 33 . when the water reaches the level of the nonreturn valve 22 during the filling of the flushing tank , a closing body 68 is subjected to buoyancy , as a result of which this valve is closed . as a result , the float 21 remains in its lower position until the water 50 reaches the water level a . the intake valve 4 correspondingly remains open until the flushing tank is again completely filled . when the water level a is reached , water enters the vessel 20 over its top edge , until it is finally filled again with water , and the float 21 moves the valve rod 24 upward and closes the passage opening 25 . when the intake valve is closed , the piston 37 returns to the position illustrated in fig2 via the force exerted by the spring 39 . communicating holes 81 allow water to flow from the tank into the chamber 64 , and the chamber 65 is again filled with water through the non - return valve 36 . the state shown in fig2 in which the flushing tank is ready for the next flushing , is thus again reached . as is apparent from fig2 an overflow edge 71 of the valve pipe 16 is arranged below the holes 34 in the housing 33 . a so - called water separation , which has the action of an anti - vacuum device and prevents dirty water from being drawn back into the pipeline water , is thus achieved . in a preferred embodiment , a time delay brought about by the control device 54 is set such that flushing water is released through the nozzle 11 when the water entering the bowl 56 through the channel 51 has reached the arch 46 . when the lip seal 31 passes the openings 34 in the housing 33 , the incoming water flows freely into the tank 8 , and the downward pressure on the cylinder 30 is reduced . as such , the time during which water is discharged through the nozzle 11 is relatively short . the foregoing merely illustrates the principles of the invention . it will thus be appreciated that those skilled in the art will be able to devise various arrangements which , although not explicitly described or shown herein , embody the principles of the invention and are thus within the spirit and scope of the following claims .