0-4-2 ST saddle tank steamlocomotive # 4 "EDWARD THOMAS" of the Talyllyn Railway (gauge of 2 ft 3 in/ 686 mm) is pulling 4 empty slate transport wagons through the valley near Brynglas. The locomotive # 4 was built by Kerr Stuart & Co. Ltd. at the California Works, Stoke-on-Trent in 1921, it was delivered new to the Corris Railway where it ran until 1948. After that railway closed, the locomotive was brought to the Talyllyn Railway in 1951, then restored, and remains in working order at the heritage railway. It has carried the operating number 4 under four successive owners. Since 2010 the small engine is in deep bronze green, lined with black borders and yellow lining.