Upon receiving the petition, signed by a majority of the members of the board of trustees, the supervisors shall fix a time for hearing the petition, which shall not be more than 30 days thereafter, and shall cause a notice, stating the time and place of hearing, and the object of the petition in general terms, to be published for 10 days prior to the day of hearing in a newspaper published in the library district, if there is one, and if there is no newspaper published in the library district, then in a newspaper published at the county seat of the county in which the library district or part thereof is situated.