64 Pa. Stat. § 193
From and after the passing of this act, that in all cases of dispute or controversy respecting any boundary or boundaries in any or either of the donation districts thus respecting any lot or lots therein, as marked, surveyed and returned into the surveyor general's office, in pursuance of the act, entitled, "an act for directing the mode of distributing the donation lands promised to the troops by this commonwealth," passed March 24, 1785, the general drafts of the said surveys as returned into the surveyor general's office shall be the evidence of the location of the respective lots, and official copies of the said drafts, or any or either of them, or of any part or parts thereof, shall be evidence before any court of competent jurisdiction, in order to designate the situation of any or every lot, so far as regards its relative situation with the other lots.
64 P.S. § 193