The first 19 locomotives ordered by Isambard Kingdom Brunel for the Great Western Railway included six 2-2-2 Charles Tayleur locomotives. They were built by Charles Tayleur and Company, which became later the Vulcan Foundry. The locomotives were unsuccessful and rapidly supplemented by the Star Class locomotives ordered by Daniel Gooch once he had been appointed as the Locomotive Engineer. As built, they comprised two groups of three: the first group, delivered in 1837, had cylinders having a bore of 14 inches (360 mm) and the second group, delivered in 1838, had cylinders having a bore of 12 inches (300 mm); all had a stroke of 16 inches (410 mm).