The engineers and businessmen needed to create and finance a railway system were available; they knew how to invent, to build, and to finance a large complex system. The first quarter of the 19th century involved numerous experiments with locomotives and rail technology. By 1825 railways were commercially feasible, as demonstrated by George Stephenson (1791–1848) when he built the Stockton and Darlington. On his first run, his locomotive pulled 38 freight and passenger cars at speeds as high as 12 miles per hour. Stephenson went on to design many more railways and is best known for standardizing designs, such as the "standard gauge" of rail spacing, at 4 feet 8½ inches.