to connect to Bo'ness Harbour, with a link to the E&GR west of Bo'ness Junction (later Manuel) so aligned as to allow through running from the Polmont direction to Bo'ness. The unbuilt line was absorbed into the Monkland Railways at the time of formation of that company, but the subscribed capital of £105,000 was to be kept separate. The Act of 26 June 1846 specified that the Union Canal was to be crossed by a drawbridge or swing bridge, and that screens were to be provided to avoid frightening horses drawing barges on the canal. In fact the E&GR made considerable difficulties over the construction of the new bridge to pass the S&BR line under their own main line, and construction was delayed until 1848. With a resumption of friendly relations, it now appeared that some construction could be avoided if Slamannan to Bo'ness trains used the Slamannan Junction line to Bo'ness Junction on the E&GR and then the proposed Bo'ness Junction connection towards Bo'ness, so that trains would join and then immediately leave the E&GR main line. In 1850, as construction was progressing, it was belatedly realised that the configuration of the junctions on the E&GR main line was such that a through movement would be impossible; trains would have to shunt back on the E&GR main line. In addition the E&GR made stipulations about the composition of the Monkland wagon wheels which were impracticable to comply with. Accordingly, the Monkland Railways decided (in May 1850) to complete the originally intended through line from Causewayend after all. The E&GR took umbrage at this and put further difficulties in the way of the underbridge construction and disputation dragged on until May 1851. The Monkland Railways now got a fresh Act authorising some deviations of the new line, and the substitution of a fixed bridge over the Union Canal. The approach to Bo'ness Harbour itself was to be along the foreshore there, and the Company was obliged to build a promenade on the sea side of the railway line there. John Wilson, the proprietor of important iron works at Kinneil obtained permission to run some mineral trains there while the line was still under construction, and the first trains ran from Arden on 17 March 1851, but opening from the E&GR line at Bo'ness Junction (Manuel) took place in early August 1851, with the undesirable backshunt on the E&GR main line