Sec. 2b. MONTHLY PAYMENTS OF SALARIES AND EXPENSES; PREREQUISITES. The salary and traveling expenses provided for in Sections 2 and 2a shall be paid monthly, upon the order of the County Board of Education; provided that the salary for the month of September shall not be paid until the said County Superintendent submits a certificate from the State Superintendent of Public Instruction showing that all reports required have been made to the State Department of Education. That the office expenses provided herein shall be paid by the County Treasurer on the order of the Commissioners Court as said expenses may be incurred.