It shall be the duty of the chairman of the board of county commissioners to preside at the meetings of said board, and he shall have the power to administer oaths to any person concerning any matter submitted to the board or connected with their powers and duties; and all orders made by the board of county commissioners, and all warrants drawn on the county treasurer, shall be signed by the chairman and attested by the clerk.
R.L. 1910, § 1589.