Use of one telephone or telegraph line by another; apportionment of cost

Whenever, after hearing upon notice, the board of public utility commissioners shall determine that public convenience and necessity require a physical connection for the establishment of a continuous line of communication between any two or more public utilities regularly engaged in the conveyance of telephone or telegraph messages, for the conveyance of such messages between different localities which are not reached by the lines or connections of one of such companies, the board may by order fix the just and reasonable terms and conditions of such physical connection, including just and reasonable rules and regulations, and the just and reasonable charge that shall be made to the public for the use of such continuous line and the division of the charge between the utilities and the apportionment of the cost of making the physical connection. The public utilities shall thereafter conform to such order of the board. No order shall be made by the board to apply where the physical connection will prevent those owning, operating, managing or controlling any part of the proposed continuous line of communication from performing their public duties, or result in serious injury to them.