Glossary Results for Word "Duplicate List"
|Duplicate List||When a locomotive or carriage reached the end of its accountancy or depreciation life it was normally replaced in the capital stock by a new one, which in theory replaced the older machine by another of like kind (subject to technological improvement). The new locomotive or carriage took the running number of the one displaced so as to maintain the capital stock at a constant population.
However, in many cases the old loco or carriage was not physically worn out, and was capable of further use, in some cases for many years. It was therefore transferred to what was called the “duplicate” list (locomotives) or the “supplementary” list (carriages), and assigned a different number in the series reserved for duplicate stock. If the vehicle was later broken up, then the number would be re-used. The system was complicated, but one rule was that vacated numbers were not re-issued in the same half-year, so at any given time there were never two locomotives (or carriages) with the same number.