On the first Monday of each month, detailed statements of the receipts and expenditures of the officers and departments for the preceding month shall be made to the auditor by the departmental heads. The auditor shall countersign each receipt given by the treasurer before it is delivered to the person entitled to receive it, and shall charge the treasurer with the amount thereof. If the auditor approves any vouchers contrary to the provisions of this title, he and his sureties shall be individually liable for the amount thereof.
(R.C. § 733.14)