All the grounds taken within the boundaries of the Fairmount park by the first section of this act shall be subject to all the powers and control given, by the act to which this is a supplement, to the city of Philadelphia and the park commissioners designated by or appointed under said act; and the owners of all ground taken for the park, and others interested therein, shall be compensated as in said act is directed and provided.
53 P.S. § 16506