The LMS Ivatt Class 4 2-6-0 was introduced as well as the notable "Mickey Mouse" LMS Ivatt Class 2 2-6-0 and LMS Ivatt Class 2 2-6-2T, built to replace life expired 19th century branch line 0-6-0 and motor train 2-4-2T locomotive types, and the Class WT 2-6-4T locomotives for the Northern Counties Committee.