PURPOSE: To accurately pour a predetermined amount of the chemical liquid by a method wherein the chemical liquid in a chemical liquid receiving tank is flowed into a measuring cylinder and said chemical liquid in the measuring cylinder is dripped from a pouring port under gravity by switching a flowing channel by a three-way control valve.

CONSTITUTION: In a condition wherein a valve body 22 of the three-way control valve 19 closes the second valve port 21, if a valve 34 of a supply pipe 13 is opened, the chemical liquid in the chemical liquid receiving tank 2 is passed through a filter 14 and flowed into the supply pipe 13. The chemical liquid in the supply pipe 13 is flowed into a pouring pipe 15 and, after passed through the first valve port 20, flowed into the measuring cylinder 27. When the measuring cylinder 27 is filled with the chemical liquid, a solenoid 24 is operated to raise the valve body 22. Therefore, the second valve port 21 is opened and the first valve port 20 is closed and, thereby, the chemical liquid in the measuring cylinder 2 is dripped under gravity from the pouring port 17 of a lower end of the pouring pipe 15.