Section 9. If the trustees of any town library shall vote not to keep or receive any of the books and reports which the state secretary is authorized to send thereto, the secretary, at the request of the supervisor of public records, may discontinue sending them. Any of said books and reports in the custody of any town library may be returned at its expense to the state library, or, with the sanction of the board of library commissioners, may otherwise be exchanged or disposed of.