53 Pa. Stat. § 4431
From and after the passage of this act it shall be unlawful for any keeper, owner, proprietor, or employé of any junk-shop within any city within this commonwealth, or for any owner, proprietor, or employé of any second-hand store within any such city, to barter, purchase, exchange, buy or accept from any person whatsoever, except plumbers holding licenses as such from such city, or the owner or owners of buildings from which the material is taken, any pipe, faucet, boilers, spigots, coils, or any other like material whatever, or to barter, purchase, exchange, buy, receive or accept any other second-hand goods, wares, or merchandise of any kind or nature whatever, without providing and keeping books, and making therein at the time of such purchase, exchange, receiving or accepting, the entries hereinafter provided.
53 P.S. § 4431