53 Pa. Stat. § 16365
All and singular the duties, rights and powers of the city of Philadelphia, concerning all property and estate whatsoever, dedicated to charitable uses or trusts, the charge or administration of which is now or shall hereafter become vested in or confined to the city of Philadelphia, shall be discharged by the said city through the instrumentality of a board composed of fifteen persons, including the mayor of said city, the presidents of the select and common councils for the time being, and twelve other citizens, appointed as hereinafter provided, to be called directors of city trusts, who shall exercise and discharge all the duties and powers of said city, however acquired, concerning any such property appropriated to charitable uses, as well as the control and management of the persons of any orphans or others, the objects of such charity, to the extent that the same have been or hereafter may be, by statute law or otherwise, vested in or delegated to the said city or the officers thereof.
53 P.S. § 16365