If it be objected on the part of any property assessed for such improvement, that it will not be benefited thereby to the amount assessed thereon, and that it is assessed more than its proportionate share of the cost of such improvement, and a jury be not waived by agreement of parties, the court shall impanel a jury to try the said issue, and in such case, unless otherwise ordered by the court, all such objections shall be tried and disposed of before a single jury. The assessment roll, as returned by the officer making the same, or as revised and corrected by the court on the hearing of the legal objections, shall be prima facie evidence of the correctness of the amount assessed against each objecting owner but shall not be counted as the testimony of any witness or witnesses in the cause. Such assessment roll may be submitted to the jury and may be taken into the jury room by the jury when it retires to deliberate on its verdict. Either party may introduce such other evidence as may bear upon the said issue or issues. The hearing shall be conducted as in other cases at law, and if it shall appear that the premises of any objector are assessed more than they will be benefited by the said improvement, or more than its proportionate share of the cost of such improvement, the jury shall so find, and shall also find the amount for which such premises ought to be assessed, and judgment shall be rendered accordingly.