Amending the act of May 11, 1889 (P.L.188, No.210), entitled "A further supplement to an act, entitled 'An act to establish a board of wardens for the Port of Philadelphia, and for the regulation of pilots and pilotage, and for other purposes,' approved March twenty-ninth, one thousand eight hundred and three, and for regulating the rates of pilotage and number of pilots," further providing for rates of pilotage and computation, for pilotage fees and unit charge and for charges for services.