TheEach expense of incurred for repair and maintenance pursuant to § 31-13-19 shall must be paid, on the presentment of itemized and verified vouchers approved by the county highway superintendent, to the county auditor, by warrants drawn on the county treasurer payable out of township funds belonging to the township which are in the hands of the county treasurer or out of the first funds belonging to such township which thereafter come into the county treasury; but such. The expense incurred by the county highway superintendent shall may not exceed the sum of two thousand and five hundred dollars for any one each mile of road during any each year. 11