Under the Whyte notation for the classification of steam locomotives, 4-6-4 represents the wheel arrangement of four leading wheels on two axles, usually in a leading truck, six powered and coupled driving wheels on three axles, and four trailing wheels on two axles, usually in a trailing truck. In France, where the type was first used, it is known as the Baltic, while it became known as the Hudson in most of North America. Other equivalent classifications are: UIC classification: 2C2 (also known as German and Italian classifications) French classification: 232 Turkish classification: 37 Swiss...