Highland Railway X Class

The Highland Railway Drummond 0-6-4T, known as the X class, were large tank engines designed by Peter Drummond and originally intended for banking duty. The first four were built by the North British Locomotive Company and delivered in 1909, and a second batch of four was delivered in 1911. The design was derived from the railway's Class K 0-6-0 tender engines, with a larger boiler and firebox. Crews did not like them, finding them heavy and clumsy, with problems of water capacity and axleboxes that ran hot. All entered London, Midland and Scottish Railway ownership in 1923 and were renumbered 15300 to 15307, and withdrawal ran from 1932 to 1936.