A liquid dispensing circuit is provided with: a multi-way cock (1) a first line a second line a third line a fourth line a fifth line and a casing which houses some of the above. When a cock (3) in the multi-way cock (1) is situated in a priming position, a distal opening (334) in a second part (332) of a first flow channel (33) communicates with a first port (P1), and a distal opening (335) in a third part (333) communicates with a second port (P2) thus, the first port (P1) and the second port (P2) are in an open state wherein the ports are connected to each other via the first flow channel (33), whereas a third port, a fourth port, and a sixth port are in an open state wherein the ports are connected to one another via a second flow channel.