PURPOSE: To improve a glazing state and a treating speed by constituting the device in such a manner that the glaze slip in a glaze tank flows a specific looped flow and flows at nearly the same speed as the transporting speed of body roof tiles.

CONSTITUTION: A partition wall 4 is provided in the glaze tank 1 to form the looped flow passage consisting of a forward path 5a which passes the glaze slip 2 together with the body roof tiles 3, a backward path 5b which passes the slip opposite therefrom and communicating paths 6c, 5d which communicate both ends of the two paths 5a, 5b. The glaze slip is partly sucked from a suction port 7 toward a blank arrow 8 direction by a pump 6 and is discharged from a discharge port B in a blank arrow C direction, by which the flow velocity of the glaze slip 2 is so regulated as to be nearly equaled to the transporting speed of the body roof tiles 3. The dried body bricks 3 are suspended in this state to chucking hangers 10 of a trolley conveyor 9 and are continuously transported in a black arrow A direction, by which the body roof tiles 3 are dipped in the glaze slip 2.