Toilet bowl flush device

A toilet bowl flush device which discharges flush water in a cistern to a water discharge path for toilet bowl flushing, comprising:

• a water intake pipe having an open end in the cistern;
• a water discharge start valve for introducing priming water for starting water discharge into the water intake pipe;
• a trap for forming an air stagnation section at a position midway from the open end of the water discharge start valve of the water intake pipe, the position being at a higher position relative to the open end;
• and
• a rotational operation lever for determining an amount of flush water to be discharged, whereby the directional movement chosen and used by said operation lever selects between a first predetermined amount of flush water and a second predetermined amount of flush water,
• wherein said second predetermined amount of flush water is greater than said first predetermined amount of flush water,
• wherein when said operation lever is rotated in a first direction, said first predetermined amount of flush water is discharged, and
• wherein when said operation lever is rotated in a second, opposite direction, said second predetermined amount of flush water is discharged.