If the commission finds it to be in the public interest and to be practicable, without substantially impairing the ability of a carrier owning or entitled to the enjoyment of terminal facilities to handle its own business, it shall have power to require the use of any such terminal facilities, including main- line track or tracks for a reasonable distance outside of such terminal, of any carrier, by another carrier or other carriers, on such terms and for such compensation as the carriers affected may agree upon, or, in the event of a failure to agree, as the commission may fix as just and reasonable for the use so required, to be ascertained on the principle controlling compensation in condemnation proceedings. Such compensation shall be paid or adequately secured before the enjoyment of the use may be commenced. If under this paragraph the use of such terminal facilities of any carrier is required to be given to another carrier or other carriers, and the carrier whose terminal facilities are required to be so used is not satisfied with the terms fixed for such use, or if the amount of compensation so fixed is not duly and promptly paid, the carrier whose terminal facilities have thus been required to be given to another carrier or other carriers shall be entitled to recover, by suit or action against such other carrier or carriers, proper damages for any injuries sustained by it as the result of compliance with such requirement, or just compensation for such use, or both, as the case may be.
Trunk lines, or principal railroads, shall, in the distribution of cars and the furnishing of facilities, treat industries and shippers, located on and tributary to lateral, industrial or tap lines, as if they were located directly on the track of the trunk lines or principal railroads, and not discriminate between such industries and shippers and those which may be located in direct proximity to their own tracks. And trunk lines or principal railroads shall allow and pay to the lateral, industrial or tap lines, a reasonable and equitable portion of the rate, consistent with the service rendered, giving due consideration to the fact that such lateral, industrial or tap line originates and assembles the freight. But nothing out of the main line rate shall be allowed the shipper or owner for the use of what may be termed "plant facilities."