1791 Pa. Laws 105, A Supplement to the Act, Entitled “An Act for Securing the City of Philadelphia and the Neighborhood Thereof from Damage by Gun-powder, § 1.

That it shall and may be lawful for the owners of gun-powder not deposited , or to be deposited, in the said magazine, the square to the south of Vine street, to remove and deposit the same in the said new magazine; and all gun-powder brought into the city of Philadelphia, from and after the first day of July next, shall be deposited and kept in the said new magazine subject to the regulation contained in the said first recited act.