36 Pa. Stat. § 3422
The word "bridge," whenever used in this act, shall include the actual bridge between the shore lines of the river and the approaches thereto, including the substructures and superstructures of both. The word "approaches," whenever used in this act, shall be construed to mean all that portion of the bridge extending from the beginning of the approach to the furthermost abutment of the bridge on the same side of the river, but not to include such abutment. The word "superstructure," whenever used in this act, shall be construed to mean all that portion of the bridge between the approaches. The term "substructure," whenever used in this act, shall include all that portion of the bridge not included within the meaning of the definition of superstructure or the approaches, and shall include the piers and abutments. The term "cost of construction," as used in this act, shall include the cost of constructing the superstructure and substructure of the bridge and the approaches thereto, and the cost of acquisition of the ground for the site of said bridge and the approaches thereto, including any franchises, easement, rights, or damages incident thereto or consequent upon the taking thereof. The "Pennsylvania Commission," as used in this act, shall be construed to mean the Governor, the Auditor General and the State Treasurer of the Commonwealth of Pennsylvania, the Mayor of the city of Philadelphia, and four other citizens of the Commonwealth, to be appointed by the Governor. The term "interstate bridge commission," as used in this act, shall be construed to mean the New Jersey Inter-state Bridge and Tunnel Commission. The "joint commission," as referred to in this act, shall mean the New Jersey Inter-state Bridge and Tunnel Commission and the Pennsylvania Commission, acting as a joint commission for and on behalf of the Commonwealth of Pennsylvania and the State of New Jersey. The term "owner," as used in this act, shall be construed to mean all individuals, incorporated companies, and religious, benevolent, literary, or other societies or associations, having any title or interest in lands, structures, rights of way, franchises, easements, or other interests in lands.
36 P.S. § 3422