The proceeds of the sale of state highway bonds shall be received by the State Treasurer and applied by him to the purposes for which issued, except that the accrued interest, if any, shall be used to discharge in part the first interest to become due on such bonds, and the premium, if any, shall be used to discharge the payment of the first installment of principal to become due on such bonds, but the purchasers of such bonds shall in no wise be liable for the proper application of the proceeds to the purposes for which they are intended.