The county board of each county in this state may borrow money in an amount sufficient to pay all valid, legally existing warrants of the county hereafter drawn on any county fund, which is legally entitled to participate in the annual allocation of revenue, but subject to the following limitations and requirements, to wit:

(1) Money shall not be borrowed in excess of the amount required to pay warrants issued and embraced within the limits imposed by law upon the right of a county to draw and issue warrants.

(2) The money so borrowed may not be used for any purpose other than payment of such warrants.

(3) The obligation thus incurred shall be evidenced by a negotiable promissory note or notes issued in the name of the county, signed by the chairman of the board and witnessed by the county clerk.

(4) The note may run for not more than one year, but shall be callable by the county at any time, and may draw interest at a rate to be determined by the county board.

(5) Such note or notes, before being negotiated, shall be presented to the county treasurer of the county and registered by said officer, and shall be payable out of the revenue collected, received and credited to such fund or funds.