Section 18. If a suit, in which the right of a body politic or corporate to effect a particular public improvement or to make a particular taking is drawn in question, is brought within the time for filing a petition to the proper tribunal for an award or assessment of the damages caused by such improvement or taking, or within six months after the determination of an earlier suit involving the same question, brought within the time for filing such petition, which failed for want of jurisdiction, defect of form or other like cause not decisive of the merits of the controversy, the petition may be filed within six months after the final determination of such suit.