R.I. Gen. Laws § 39-9-4: Charges for transfer of shipments to connecting line.

Whenever merchandise is transported over any portion of two (2) railroads that form a connecting line, and the tracks of which so unite that cars can pass from one to another, no charge shall be made for the loading or unloading or for the carriage of the merchandise from the cars of one of the railroads to the cars of the other.