If, at any time, the state controller, upon an examination of the books and accounts of any treasurer of any county, and the funds under the control, or in the custody of, such treasurer, as authorized by law, shall find that any such treasurer is a defaulter, he shall at once report such defalcation or inability of such treasurer to the board of county commissioners of the county interested, which board of county commissioners shall, upon receiving such notice, have authority to suspend such treasurer, and to appoint a treasurer temporarily, and to continue such suspension until such defalcation shall have been made good: provided, however, that such board of county commissioners shall have power, in case it shall appear to their satisfaction that such defalcation cannot be made good, to declare said office vacant, and to fill the same by appointment as required by law in case of vacancies arising in any such office.