The select and common councils of the city of Allegheny are hereby authorized and empowered to pass ordinances to establish scales, or some other method to ascertain the weight of coal sold within the limits of said city, and to regulate and compel persons to use said scales, or other mode of weighing coal, and may impose such penalties and forfeitures as they may think proper (not exceeding one hundred dollars for any offense), for violating the provisions of said ordinances.
16 P.S. § 11907