16 Pa. Stat. § 8351
In case any of said claimants shall appeal from the award of said viewers, the said county commissioners may, upon filing in the said court, and having approved thereby, a bond in double amount of said award to the said owners and claimants for the benefit of the persons owning said ground, with at least two sufficient sureties, conditioned for the payment by the county of such an amount as the owner or owners shall be entitled to receive for said ground, when the same shall have been finally ascertained by due course of law, lawfully enter upon and take possession of said ground, and the said court shall thereupon proceed to determine the estates and interests of said claimants in said ground, as is hereinbefore provided, when the valuation money is paid into court. Which said proceedings shall be finally determined before the issue framed upon the said appeal shall be tried, and if it be determined that the party appellant has no estate or interest in said ground, his appeal shall be disallowed.
16 P.S. § 8351