Horse traction was used on the level sections between the inclined planes. From September 1833 steam locomotives were introduced: no. 1, "Earl of Airlie" and no. 2, "Lord Wharncliffe" were delivered (on 20 and 25 September respectively) from J and C Carmichael of Dundee. They had the 0-2-4 wheel arrangement. They had single-acting vertical cylinders driving the front wheels through bell cranks; the trailing wheels were mounted in a bogie, a very early implementation of that construction. A third locomotive, no. 3, nicknamed "Trotter" was delivered from James Stirling and Co on 3 March 1834; it was similar to the earlier engines, but a little smaller. A fourth engine, named "John Bull", was acquired from Robert Stephenson & Co in April 1836. It was an 0-4-0 of the "Planet" type. The four locomotives cost about £3,300.