LNWR 3P 4-6-2T No 1186 up fast on Bushey troughs in c1920.
1186 is an example of one of Bowen-Cooke's superheated 4-6-2 tanks first introduced in 1910 thus prior to the 4-6-0 Prince of Wales class appearing. 1186 entered traffic in March 1911 and was initially non-superheated in which condition it is shown here but received Superheating in March 1914 so the photo was probably taken early in its life pre WW1. Note the absence of the electrified suburban lines to Watford Junction which were not completed until 1917


Photo: H. Gordon Tidey / Rail Archive Stephenson