[1] 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.
[1] 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.
[9] 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.