SECTION 1. Act Numbered Five hundred and fifty-five, entitled "An Act to authorize the construction by the Manila Railway Company, Limited, owning and operating the Manila and Dagupan Railway, of two branches, one connecting Mabalacat with the main line, and one connecting Bayambang with the main line," is hereby amended by adding thereto the following sections:
"SEC. 5. The Manila Railway Company shall pay into the Treasury of the Insular Government as compensation for the granting of this franchise one and one-half per centum upon its gross income received by it from the passenger and freight traffic upon said branch railways, one connecting Mabalacat with the main line, and one connecting Bayambang with the main line. Where receipts either from freight traffic or passenger traffic shall include transportation over part of the main line and either or both of the branches herein authorized, the receipts for traffic on the branch lines shall be determined in proportion to the mileage. Said percentage of gross receipts shall be due and payable by the Manila Railway Company, Limited, monthly, and shall be in lieu of all taxes upon the privileges, earnings, income, and franchises of said railroad company, from other tax and assessments upon which said railway company is hereby expressly exempted for twenty years from the passage of this Act.
"SEC. 6. The Manila Railway Company, Limited, shall keep a record of all its receipts for the carriage of freight and passengers over the lines herein authorized, which shall be subject to the inspection of the authorities of the Insular Government, who shall audit and approve the accounts of the company at the end of each month before the payment of the percentage tax. The amounts when audited and approved as herein provided shall be conclusive evidence of the liability of the company under the provisions of section five."