The judges of the Supreme Court shall appoint a librarian for the Supreme Court Library, located at the Supreme Court Building, and prescribe his duties and fix his compensation to be paid as other expenses of the Supreme Court are paid. Such librarian, before entering upon the duties of his office, shall give bond payable to the People of the State of Illinois in the penal sum of $5,000 with security to be approved by 2 judges of said court conditioned for the due preservation of the books belonging to the library, in his charge, and for the faithful performance of his duties as such librarian.