This fascinating loco actually has a vertical water-tube boiler, which can be seen in the cab. The chimney (smokestack) can be seen directly up from the boiler and sticks out through the cab roof. The boiler powers a multiple-cylinder, high speed enclosed engine. The cylinders are actuated by poppet valves and the final drive is by chain, which can be seen around the driving wheels. The loco was built by Sentinel in 1929. The company built around 850 locos of the type, but few are now left .