Although a short line, it succeeded in achieving profitability, eventually being absorbed on generous terms by the Glasgow and South Western Railway.

At this early date, thought was given to reaching Portpatrick, which was the port for a short sea route ferry service to Donaghadee in the north of Ireland.

The G&BUR was to run by way of Patna, and a third line was proposed to cross the wild country of Galloway, the Ayrshire and Galloway Railway (A&GR); it would form a junction with the G&BUR at Smithston, near Patna, and run through Dalmellington to Castle Douglas, there linking with the British and Irish Union Railway.

The frenzy of railway schemes lasted for a while but then the bubble burst in 1846, and ambitious and expensive proposals found that they could not get the financial support they needed.

The B&IUR announced that it was not proceeding on 21 April 1846, and the A&GR scheme was cut back drastically, to run from Smithston to Dalmellington only, a tiny fraction of its intended extent.

The G&BUR was authorised in the face of grave financial difficulty, and when the shareholders considered the reality of the situation, the decision was taken not to proceed with construction, and the expensively-won powers were allowed to lapse.

[2][1] In October 1850, the GPK&AR merged with another company and the Glasgow and South Western Railway (G&SWR) was created.

The lure of reaching Portpatrick remained, and at the end of 1852, the prospectus for an Ayr, Maybole and Girvan Railway was published.

Yet another truncated scheme was presented to Parliament in the 1854 session, and this time it was passed, as the Ayr and Maybole Junction Railway Act 1854 (17 & 18 Vict.

The negotiations dragged on and the G&SWR agreed a "perpetual working agreement" with a sliding scale of charges between 39% and 45% of gross receipts.

[1][4][5] When the company was originally promoted, a direct rail connection between Glasgow and Portpatrick was contemplated; the A&MJR saw itself as a link in that chain.

The G&SWR vice chairman was asked to explain the generous terms at the extraordinary general meeting called to ratify the deal, and he replied that "we could not get it for less".

[9] The Maybole terminus closed to passengers on 24 May 1860 when the Girvan line opened; it remained in use as a goods depot until closure in 1965.