Steam Locomotives of a More Leisurely Era
1895 Rack Locomotives
Snowdon Mountain Railway
For working Britain’s only mountain railway, with its gradient of 1 in 5½, special locomotives incorporating the ‘ABT’ rack-and-pinion system have to be used. This consists of a double rack of steel between the running rails, which engage the teeth of the two geared cogwheels fitted to the engine. The teeth of each rack are staggered so that at least three teeth are in gear at any one moment. The maximum speed is about 5 mph both up and down. The locomotives, which always face up the mountain, have inclined boilers which preserve an approximately horizontal position when the engine is on the gradient. They were constructed by the Swiss Locomotive Company, and are of a type at one time widely employed in that country, with its numerous mountain railways, all of which are now, however, electrified.
Snowdon Mountain Railway. No.2 ‘Enid’ SLM 0-4-2T 924 of 1895, at Llanberis Shed, shunting at the end of the day. Most visitors never see the front of these engines as they always push the carriages. 19th July 2005 Photographer – A.M.Hurrell This file is licensed under the Creative Commons Attribution 2.5 Generic license.
The first three engines were No.1 ‘Ladas’, 2 ‘Enid’ and 3 ‘Wyddfa’, built in 1895, followed by two more, No.4 ‘Snowdon’ and No.5 ‘Moel Siabodd’ in 1896. Three more of an improved design followed in 1922-3, Nos.6 ‘Padarn’, 7 ‘Aylwin’, and 8 ‘Eryri’.
Snowdon Mountain Railway. No.6 ‘Padarn’ SLM 0-4-2T 2838 of 1922, at Llanberis Shed, waiting for its first duty of the day. 19th July 2005 Photographer – A.M.Hurrell This file is licensed under the Creative Commons Attribution 2.5 Generic license.
No.1 had a very short life indeed as it was blown over the mountainside in a gale in 1896, and never recovered. The others are still in existence but No.4 has not worked since 1939. (As in 1959).
Gauge of railway – 2’ 7½”, Driving wheels – 655 mm (Approx 2’ 1¾”), Cylinders – 300 mm x 600 mm (Approx 11¾” x 23¾”), Pressure – 200 lb., Rack pinions – 1’ 10¼” diameter, Weight 17¾ tons (Nos. 1-5), 18½ tons (Nos.6-8).
Upward train as seen from a downward train. © Copyright Christine Matthews and licensed for reuse under this Creative Commons Licence.