64 Pa. Stat. § 194
It shall be the duty of the deputy surveyor of the proper district or county, on application made to him by any person interested, to run and distinctly mark the lines of any lot or lots, and to remark the original corners, agreeably to the true meaning and intention of the first section of this supplement; and in order to carry this into effect, it shall be the duty of the surveyor general to furnish each deputy surveyor, free of expense, with a certified copy of the general draft of the donation lands so far as they lie in his district or county, which shall be open to the inspection of any person or persons, they paying the customary fees: Provided, That nothing in this act contained shall be construed to affect the right of bona fide purchasers, in cases where the original marked lines can be ascertained.
64 P.S. § 194