Chapter XVIII: Section 13: authorizes any person, firm, corporation or association, any

mercantile, agricultural or manufacturing society, any body politic or municipal organization to file complaints against any common carrier subject to the provisions of the act, with the commission, whose duty it is made to forward a statement of the charges to such common carrier and call upon him to satisfy the complaint or answer the same in writing, and to investigate the matters complained of, if the complaint is not satisfied. The commission is also charged with the duty of making such investigations at the request of State or territorial railroad commissions and may even institute them at its own motion. Section 14 requires the commission to make a report in writing of any investigation it may make and to enter it of record and furnish copies of it to the complainant and the common carrier complained of. Section 15 makes it the commissioners' duty, when it is found that any law cognizable by it has been violated by a common carrier, to serve notice on such carrier to desist from such violation and to make reparation for an injury found to have been done. If any lawful order or requirement of the commission is disobeyed by a common carrier, it becomes their duty and is lawful for any company or person interested in such order to apply by petition to the Circuit Court of the United States sitting in equity in the judicial district in which the common carrier complained of has its principal office, and the court has power to hear and determine the matter speedily and without the formal pleadings and proceedings applicable to ordinary suits, and to restrain the common carrier from continuing such violation or disobedience. It is further provided by this section that on such hearings the report of the commission shall be accepted as _prima facie_ evidence.