21 Pa. Stat. § 187
All deeds, mortgages or other instruments of writing, heretofore made or which may hereafter be made by any person or corporation, concerning lands, tenements, hereditaments or property, or any estate or interest therein, lying or being within this commonwealth, heretofore acknowledged or proved, or which may hereafter be acknowledged or proved, in the manner directed and provided by the laws of this commonwealth, before any person holding the rank of major or any higher rank in the military service of the United States in Cuba, or in Porto Rico, the Philippine Islands, or other possessions of the United States, whether in the regular or volunteer service, or before any civil officer in the service of the United States in any of the said places hereinbefore referred to, shall be valid to all intents and purposes, and be in like manner entitled to be recorded as if the same had been duly acknowledged and proven before a notary public or other officer within this commonwealth having authority to take such proofs or acknowledgments according to the existing laws of this commonwealth.
21 P.S. § 187