Athens was dropped from the railroad name on 18 February 1885,[REF] and the Monson Railroad requested legislative authorization to extend the main line south from Monson Junction for connection with the standard gauge Sebasticook and Moosehead Railroad (later the Maine Central Railroad Harmony branch.)
Portland Slate Company built a new mill on the Monson Main line in 1904, and six new flat cars were built by Laconia Car Company in 1905 to handle loadings from the new shipper.