All viewers and reviewers appointed for any purpose mentioned in this act, also all persons appointed to inspect any bridge as aforesaid, shall, before they proceed to the duties of their appointment respectively, make oath or affirmation to perform the same impartially, and according to the best of their judgment, which oath or affirmation may be administered to them by any magistrate of the respective county, or by any one of their number.
36 P.S. § 1784