LB&SCR H1 Class:
The London, Brighton and South Coast Railway H1 class was a class of 4-4-2 steam locomotives for express passenger work. They were designed by D. E. Marsh and were built by Messrs Kitson & Co. in 1905 and 1906.
Prior to taking up office as the Locomotive Superintendent of the London, Brighton and South Coast Railway in 1905, Douglas Earle Marsh had worked for the Great Northern Railway at Doncaster Works. There he had been involved in the design of the Klondyke class designed by Henry Ivatt in 1897. There was an urgent need for new large express passenger locomotives for the LB&SCR and so he obtained a set of drawings from Doncaster, and made only detailed amendments before ordering them from the manufacturer. He did however increase the boiler pressure from 175 to 200 pounds per square inch (1.21 to 1.38 MPa).