Railway was promoting a new trunk line from Carlisle to Glasgow and Edinburgh; it got its authorising Act of Parliament in 1845 and opened in 1847 - 1848. It sought acquisition of the Wishaw and Coltness Railway and the Garnkirk and Glasgow Railway to get access to Glasgow, and it concluded a lease of those lines. Suddenly those lines were out of the group of mutually friendly coal railways, and soon they were simply part of the Caledonian Railway. The three other coal railways (M&KR, Ballochney and Slamannan) decided that their interests lay in collaboration, and they formed a joint working arrangement from 29 March 1845; in effect the three companies worked as one. In 1844 the M&KR had built a short spur to transshipment sidings with the E&GR at Garngaber, a little east of the present-day Lenzie station. The inconvenience of the transshipment emphasised the disadvantage of the now non-standard track gauge, and it was decided to change the track gauge to standard gauge. They got Parliamentary authority and made the change on 26 July and 27 July 1847. Operating costs were high: from 1845 to 1848 the ratio for the three railways that formed the Monkland Railways averaged 55%. Giving evidence at the hearing of the Monklands Amalgamation Bill in 1848, George Knight, secretary and General Manager of the three railways explained that: The Monklands complex consisted of 36 miles of railway proper and 12 miles of sidings, and had connected it with another 48 miles of private railways built by the various extractive and industrial interests. Although a through journey of 25 miles was possible on the system—from the eastern end of the Slamannan to the Kirkintilloch canal basin—30% of all traffic travelled less than a mile, and half of it less than 2½ miles. Hence locomotives were involved in a ceaseless pattern of stopping and shunting, and averaged only 24 miles per day against the 90 miles normal on the Edinburgh & Glasgow. The sidings were expensive to work, and even private sidings required main line points which had to be renewed every three or four years ... these numerous points also meant the employment of a large number of men to supervise them. Traders could also benefit from using the company's waggons, and were not charged for their use on sidings and private lines. [The waggons] averaged only 5¼ miles per day against 23 miles