No money shall be drawn from the treasury except upon the warrant of the Mayor, countersigned by the Clerk. Every warrant shall specify the fund from which it is payable, and shall be paid from no other fund. No warrant shall be drawn upon the treasury after the fund from which it should be paid has been exhausted, and if such warrant shall be drawn, it shall be void.
No warrant shall be issued until the same has been first authorized by the Council; provided, however, that warrants may be issued for the payment of labor without prior authorization of the Council if authorized by the Mayor, but the total amount of such warrants issued between any successive regular meetings of the Council shall not exceed an amount as the Council may from time to time establish.
All liquidated accounts and demands against the City shall be received and audited by the Clerk, who shall enumerate them on a regular form prescribed by Council and who, with the Mayor, shall certify as to the correctness or incorrectness of the various amounts on said list. Each invoice shall be approved by the official incurring the expenditure.