Crampton locomotive

The main British builders were Tulk and Ley and Robert Stephenson and Company.

This helped to give this design a low centre of gravity, so that it did not require a very broad-gauge track to travel safely at high speeds.

Another feature on some Crampton locomotives was the use of a boiler of oval cross-section, to lower the centre of gravity.

It was later seen as a major flaw, because the internal pressure would tend to push the boiler into a circular cross-section and increase the risk of fatigue.

Crampton locomotives were used by some British railways and speeds of up to 120 km/h (75 mph) were achieved on the LNWR.