If the board shall find that such improvement will materially benefit said lands, will be conducive to the public health, convenience, welfare, benefit, or utility, and that the law has been complied with as to form and substance of the petition, the service of notice, and the survey and report of the engineer, and that said improvement should be made, then if any claims for damages shall have been filed, further proceedings shall be continued to an adjourned, regular, or special session, the date of which shall be fixed at the time of adjournment, and of which all interested parties shall take notice, and the auditor shall appoint three appraisers to assess damages, one of whom shall be an engineer, and two freeholders of the county who shall not be interested in nor related to any person interested in the proposed improvement, and the said appraisers shall take and subscribe an oath to examine the said premises, ascertain and impartially assess all damages according to their best judgment, skill, and ability.