Article snapshot taken from Wikipedia with creative commons attribution-sharealike license.
Give it a read and then ask your questions in the chat.
We can research this topic together.
During 1860, the LCDR had ordered 29 passenger locomotives designed by Thomas Russell Crampton, the Tiger and Echo classes, which were subsequently delivered during 1861 and 1862. A further five Echo class locomotives had been provisionally ordered by Crampton from Sharp, Stewart and Company, but in late 1860 or early 1861, once Martley was in full control, he decided to cancel these in favour of five 2-4-0s from the same makers of a new design.
The order for what were to become the Dawn class was placed with Sharp Stewart in February 1861, for five locomotives with tenders at £3,234 each. As with the Tiger, Echo and Acis classes, the locomotives were equipped with the Cudworth coal-burning firebox. On a visit to Sharp Stewart to check on the progress of the Dawn class together with seven Acis class locomotives that were also being built there, Martley decided to cancel one of the Acis class locomotives and substitute it with one more of the Dawn class, bringing the totals to six of each. The six members of the Dawn class were delivered to the LCDR between October and November 1862. Whilst they were being delivered, a further six were ordered in October 1862, also from Sharp Stewart. These incorporated several design changes, and because of this they were known as the Bluebell class. They were delivered between April and June 1863.
Compared to the Dawn class, the Bluebell class had a boiler three inches smaller in diameter, but six inches longer, with the wheelbase increased by the same amount. Different materials were used for some components. Various modifications carried out at intervals between 1868 and 1893 eliminated some of the differences between the two classes, but also introduced differences within each class.
Like other LCDR locomotives delivered prior to 1874, the locomotives had no numbers at first, being distinguished by name. In November 1875, William Kirtley (who had replaced Martley following the latter's death in 1874) allotted the class letter N to the Dawn class, and P to the Bluebell class. The locomotives were then given the numbers 32–43, but the names were usually retained until the boiler was next replaced. All were still in service when the South Eastern and Chatham Railway (SECR) was formed at the start of 1899: their numbers were increased by 459 to avoid duplication with former South Eastern Railway locomotives, and so they became SECR nos. 491–502. Six (nos. 492–4/8/9, 502) were transferred to the duplicate list in 1903 and 1904 when their numbers were needed for new locomotives, and their numbers were suffixed with the letter "A". Withdrawal occurred between October 1903 and May 1908.
.jpg){kind=small}
