Upon the return of said summons, or as soon thereafter as the business of the court will permit, the said court shall proceed to the hearing of such petition and shall adjudicate whether the proposed condemnation is for a public use, and if its judgment is that the proposed use is public, it shall empanel a jury to ascertain the just compensation to be paid for the lands or property taken or damaged, unless a jury be waived; but if any defendant or party in interest shall demand, and the court shall deem it proper, separate juries may be empaneled as to the separate compensation or damages to be paid to any one or more of such defendants or parties in interest. Should the court determine that the proposed use is not public, it shall dismiss the proceeding.