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Salamanca was the first commercially successfulsteam locomotive, built in 1812 byMatthew Murray ofHolbeck, for theedge-railedMiddleton Railway betweenMiddleton andLeeds, England[1] and it predatedStephenson's Rocket by 17 years.[2] It was the first to have two cylinders. It was named after theDuke of Wellington's victory at theBattle of Salamanca which was fought that same year.
Salamanca was also the firstrack and pinion locomotive, usingJohn Blenkinsop's patented design forrack propulsion. A single rack ran outside thenarrow gauge tracks and was engaged by a largecog wheel on the left side of the locomotive. The cog wheel was driven by twin cylinders embedded into the top of thecentre-flue boiler. The class was described as having two 8"×20" cylinders, driving the wheels through cranks. The pistoncrossheads slid in guides, rather than being controlled by aparallel motion linkage like the majority of early locomotives. The engines saw up to twenty years of service.[3]
It appears in the first painting of a steam locomotive, a watercolour by George Walker (1781–1856) published in hisThe Costume of Yorkshire.[4]Four such locomotives were built for the railway.Salamanca was destroyed six years later, when itsboiler exploded. According toGeorge Stephenson, giving evidence to a committee ofParliament, the driver had tampered with the boiler's safety valve.[5]
Salamanca is probably the locomotive referred to in the September 1814 edition ofAnnals of Philosophy: "Some time ago a steam-engine was mounted upon wheels at Leeds, and made to move along a rail road by means of a rack wheel, dragging after it a number of waggons loaded with coals." The item continues to mention a rack locomotive about a mile north of Newcastle (Blücher atKillingworth) and one without a rack wheel (probablyPuffing Billy atWylam).[6]
A model of the locomotive, built by Murray in 1811, is part of the collection held atLeeds Industrial Museum, and is the world's oldest model locomotive.[7]