An Act amending the act of May 29, 1945 (P. L. 1134, No. 405), entitled "An act to create a commission to act jointly with commissions appointed for like purpose by the States of West Virginia and Maryland, the Commonwealth of Virginia and the District of Columbia, which, together with three members to be appointed by the President of the United States, shall constitute the Interstate Commission on the Potomac River Basin, with power to cooperate in the abatement of the existing pollution, and in the control of future pollution of the waters of the drainage basin of the Potomac River within the States of Maryland and West Virginia, the Commonwealth of Virginia and the District of Columbia;....," further providing for the members of the Interstate Commission on the Potomac River Basin for the Commonwealth.