Under the Whyte notation system, a steam locomotive that has two leading wheels followed by two sets of coupled driving wheels, and no trailing wheels.

Under the Whyte notation system, a steam locomotive that has four leading wheels arranged in a leading truck, eight coupled driving wheels and six trailing wheels in a trailing truck. The C&O had one planned as their class J4, but it was never built.

Under the Whyte notation system, a steam locomotive that has four leading wheels arranged in a leading truck, eight coupled driving wheels and two trailing wheels in a trailing truck.

Under the Whyte notation system, a steam locomotive that has a four-wheel leading truck followed by a single driving axle.

Under the Whyte notation, a steam locomotive that has six coupled driving wheels followed by four trailing wheels, with no leading wheels.

Under the Whyte notation system, a steam locomotive that has two leading wheels arranged in a leading truck, four coupled driving wheels and two trailing wheels in a trailing truck.

Under the Whyte notation system, a steam locomotive that has four coupled leading wheels, ten coupled driving wheels, and one pair of trailing wheels.

Under the Whyte notation system, a steam locomotive that has two leading wheels followed by two coupled driving wheels and four trailing wheels.

Under the Whyte notation system, a steam locomotive that has four leading wheels arranged in a leading truck, two driving wheels and two trailing wheels.

Under the Whyte notation system, a steam locomotive that has four coupled leading wheels, twelve coupled driving wheels, and one pair of trailing wheels.