No order shall be drawn on the county treasurer unless authorized by a special order or appropriation of the county court, except that when any bond, note or written evidence of the debt of the county, or any installment of interest thereon, is payable, or where money is directed by law to be paid at fixed times or intervals, as in the cases of officers entitled to an annual salary payable at stated intervals, the president and clerk of such county court, without such special order or appropriation, may make and deliver to the person entitled thereto an order on the county treasurer for any sum so due and payable.