Construction history The prototype E850 named Lord Nelson was ordered from Eastleigh railway works in June 1925 but production proceeded slowly, at Maunsell's insistence, to ensure that the weight was kept to a minimum at every stage, so the locomotive did not appear until August 1926. It was tested on a variety of duties over the next year, with sufficiently encouraging results for an initial order for ten more locomotives for delivery between May 1928 and April 1929 to be placed. These were originally scheduled to be allocated to Battersea depot and fitted with 4,000 gallon 6-wheeled tenders suitable for the Continental ports. However, during construction, it was decided to equip half of the class with 5,000 gallon 8-wheeled tenders necessary for the longer West of England routes and to allocate them to Nine Elms depot. A further batch of ten locomotives was ordered in 1928, before the previous batch had been delivered, but when it became apparent that the Stock Market Crash of 1929 would be likely to reduce the demand for Continental travel, this second order was reduced to five. Naming the locomotives The locomotives were all named after famous Royal Navy admirals, with the doyen of the class being named Lord Nelson. As a result, the rest of the locomotives belonged to the Lord Nelson (LN) class. Modifications The performance of the new locomotives was mixed, depending upon the experience of the crew and the circumstances under which they were operating. At times it was no better than their smaller predecessors. Maunsell therefore undertook a number of experiments to try to improve the performance of the new locomotives. No. E859 was fitted with smaller driving wheels to see if this would improve performance over the heavily graded London-Dover line, but the difference was marginal. No. E860 was fitted with a longer, heavier boiler but once again with little improvement. The whole class however benefitted from the fitting of smoke deflectors during the late 1920s. Maunsell was aware of the reputation for poor steaming enjoyed by the class and attempted to address it by the fitting of twin Kylchap blastpipes to No. 860 in 1934. However, the problem was ultimately solved by Oliver Bulleid, Maunsell's replacement as Chief Mechanical Engineer of the Southern in 1938. He fitted larger diameter chimneys and Lemaître multiple jet blastpipes, which effectively transformed their performance. Thereafter the class was highly respected. Operational details