LB&SCR I2 class

The LBSCR I2 class was a class of 4-4-2 steam tank locomotives designed by D. E. Marsh for suburban passenger service on the London, Brighton and South Coast Railway. The I4 class were of the same design but incorporated a superheated boiler.

I2 class

In 1907, following the failure of his I1 class, Douglas Earle Marsh sought to fix some of their flaws with a new 4-4-2T design with a longer wheelbase, larger boiler and detailed changes to the front end.Template:Sfn In the original order, five of the locomotives would incorporate a superheated boiler to be supplied by the North British Locomotive Company, and the remainder traditional saturated steam boilers from Brighton railway works.Template:Sfn In the event, the superheated boilers were delayed in construction and so all ten I2 locomotives had traditional boilers.Template:Sfn

I4 class

File:LBSCR I4.jpg

An I4 incorporating a superheated boiler

When the superheated boilers eventually arrived they were used for five further locomotives of the same design as the I2, but these were classified as I4.Template:Sfn

However neither the I2 nor I4 class addressed the fundamental problems with the I1 class, that being a small firebox.Template:Sfn As a result, the two classes had relatively short lives working lightly loaded secondary services, and the Stroudley D1 and Billinton E4 classes which they were meant to replace continued working.

Numbering

LB&SCR numbers were 11-20 and 31-35. The Southern Railway, which acquired the locomotives in 1923, initially numbered them B11-B20, B31-35 and later 2011-2020, 2031-2035.

Withdrawal

All the I2 were withdrawn between 1933 and 1939Template:Sfn but two locomotives, numbers 2013 and 2019, saw further service on the Longmoor Military Railway where they survived until at least 1947. There they were numbered 2400 and 2401 respectively. These numbers were later changed to 72400 and 72401.Template:Sfn The I4 class were withdrawn between 1936 and 1940. No examples of either class have been preserved.

Locomotive summary

I2 class locomotive fleet summary

LB&SC Number	Built	S.R. Number	Withdrawal	Notes
11	Template:Dts	2011	Template:Dts	I2
12	Template:Dts	2012	Template:Dts	I2
13	Template:Dts	2013	Template:Dts	I2, became W.D. 72400 Earl Roberts
14	Template:Dts	2014	Template:Dts	I2
15	Template:Dts	2015	Template:Dts	I2
16	Template:Dts	2016	Template:Dts	I2
17	Template:Dts	2017	Template:Dts	I2
18	Template:Dts	2018	Template:Dts	I2
19	Template:Dts	2019	Template:Dts	I2, became W.D. 72401
20	Template:Dts	2020	Template:Dts	I2
31	Template:Dts	2031	Template:Dts	I4
32	Template:Dts	2032	Template:Dts	I4
33	Template:Dts	2033	Template:Dts	I4
34	Template:Dts	2034	Template:Dts	I4
35	Template:Dts	2035	Template:Dts	I4

External links

• Marsh I2 Class 4-4-2T at semgonline.com