The Commission shall have the power and authority and be charged with the duty of supervising, regulating and controlling all transportation and transmission companies doing business in this State, in all matters relating to the performance of their public duties and their charges therefor, and of correcting abuses and preventing unjust discrimination and extortion by such companies; and to that end the Commission shall, from time to time, prescribe and enforce against such companies, in the manner hereinafter authorized, such rates, charges, classifications of traffic, and rules and regulations, and shall require them to establish and maintain all such public service, facilities, and conveniences as may be reasonable and just, which said rates, charges, classifications, rules, regulations, and requirements, the Commission may, from time to time, alter or amend. All rates, charges, classifications, rules and regulations adopted, or acted upon, by any such company, inconsistent with those prescribed by the commission, within the scope of its authority, shall be unlawful and void. The commission shall also have the right, at all times, to inspect the books and papers of all transportation and transmission companies doing business in this State, and to require from such companies, from time to time, special reports and statements, under oath, concerning their business; it shall keep itself fully informed of the physical condition of all the railroads of the State, as to the manner in which they are operated, with reference to the security and accommodation of the public, and shall, from time to time, make and enforce such requirements, rules, and regulations as may be necessary to prevent unjust or unreasonable discrimination and extortion by any transportation or transmission company in favor of, or against any person, locality, community, connecting line, or kind of traffic, in the matter of car service, train or boat schedule, efficiency of transportation, transmission, or otherwise, in connection with the public duties of such company. Before the Commission shall prescribe or fix any rate, charge or classification of traffic, and before it shall make any order, rule, regulation, or requirement directed against any one or more companies by name, the company or companies to be affected by such rate, charge, classification, order, rule, regulation, or requirement, shall first be given, by the Commission, at least ten days' notice of the time and place, when and where the contemplated action in the premises will be considered and disposed of, and shall be afforded a reasonable opportunity to introduce evidence and to be heard thereon, to the end that justice may be done, and shall have process to enforce the attendance of witnesses; and before said Commission shall make or prescribe any general order, rule, regulation, or requirement, not directed against any specific company or companies by name, the contemplated general order, rule, regulation, or requirement shall first be published one time in substance in one or more of the newspapers of general circulation published in the county in which the Capitol of this State may be located, together with the notice of the time and place, when and where the Commission will hear any objections which may be urged by any person interested, against the proposed general order, rule, regulation, or requirement; and every such general order, rule, regulation, or requirement, made by the Commission, shall be published at length, in the next annual report of the Commission. The authority of the Commission (subject to review on appeal as hereinafter provided) to prescribe rates, charges, and classifications of traffic, for transportation and transmission companies, shall, subject to regulation by law, be paramount; but its authority to prescribe any other rules, regulations or requirements for corporations or other persons shall be subject to the superior authority of the Legislature to legislate thereon by general laws: Provided, However, That nothing in this section shall impair the rights which have heretofore been, or may hereafter be, conferred by law upon the authorities of any city, town or county to prescribe rules, regulations, or rates of charges to be observed by any public service corporation in connection with any services performed by it under a municipal or county franchise granted by such city, town, or county, so far as such services may be wholly within the limits of the city, town, or county granting the franchise. Upon the request of the parties interested, it shall be the duty of the Commission, as far as possible, to effect, by mediation, the adjustment of claims, and the settlement of controversies, between transportation or transmission companies and their patrons or employees.