In early 1887 it was decided to complete the circle as originally planned; Caledonian approval was obtained for this and a Bill presented in the 1887 Parliamentary session. The G&SWR opposed the Bill, but the Royal Assent was obtained on 19 July 1887, capital £145,000. The route did not involve the difficult earthworks of the eastern section of the loop and was to be cheaper to build; cheap land was to be gifted by the Pollok Estate. Although the first section was heavily used, shareholder dividends had been considerably lower than promised and it proved difficult to generate subscriptions; after a time the Caledonian agreed to make the necessary subscription to let the line proceed. In fact the Caledonian exercised gradually increasing minority control of the CDR. An Act of 1889 had empowered it to invest £100,000 in the CDR and to guarantee the interest on the CDR's debenture stock.