Original sentence: Curiously, the first order number issued was for a batch of locomotives, but the class was referred to as 'A12' rather than 'A1'.From 1887 the principal LSWR works at Nine Elms (and, subsequently, Eastleigh) used an order number series that ran from A1 to Y1, then A2 to Y2, A3 to Z3 and so on (the letter I, J, Q, U, W an Z were omitted).Self-evidently this meant there was no continuity in the LSWR locomotive classification system
Edited sentence: Curiously, the first order number issued for a batch of locomotives was 'E1', but the class was referred to as 'A12' rather than 'E1'.From 1 January 1879 the principal LSWR works at Nine Elms (and, subsequently, Eastleigh) used an order number series that ran from A1 to Y1, then A2 to Y2, A3 to Y3 and so on (the letter I, J, Q, U, W and Z were omitted).Self-evidently this meant there was no continuity in the LSWR locomotive classification system; save that if the letters be ignored, higher figures generally meant a more modern design.The first three orders ('A1', 'B1', and 'C1') were for components: cylinders, tender wheels, and copper fireboxes respectively.The system was brought to the LSWR by William Adams from the Stratford Works of the Great Eastern Railway, where an almost identical system was in use from 1856 until after Grouping