No member of the board, nor any one connected with the board, shall have any interest, direct or indirect, in the gains or profits of any investment made by such board, nor as such, directly or indirectly, receive any pay or emoluments for his services. Nor shall any such person as an agent or partner of others borrow any funds or deposits, or in any manner use the same, except to make such current and necessary payments as are authorized by the board. Nor shall any member of said board, or anyone connected with said board, become an endorser or surety or become in any manner an obligor for moneys loaned by or borrowed of any such board.