Erika

Basis
The Great Northern Railway (GNR) Class C1 is a type of 4-4-2 steam locomotive. One, ex GNR 251, later LNER 2800, survives in preservation. Much like their small boiler cousins, they were capable of reaching speeds of up to 90 mph (145 km/h). They were also known as Large Atlantics.

The first engine, No. 251, was introduced in 1902, with eighty more being built at Doncaster Works between 1904 and 1908. Although they suffered from a number of teething troubles, the Atlantics were generally very successful. They were originally fitted with slide valves, but later gained piston valves, which produced a notable improvement in performance. The Atlantics remained in front-line service for many years, sometimes being called upon to haul trains of over 500 long tons (508 t; 560 short tons). They were known for reaching speeds of up to 90 miles per hour.

On the GNR, the classification C1 was used for all of their 4-4-2 tender locomotives, but there was considerable variation within the 116 locomotives making up this group. The LNER divided them into two classes: C2 for the 22 locomotives built in 1898–1903 with boilers of 4 feet 8 inches (1.42 m) diameter; and C1 for the remaining 94, which mostly had boilers of 5 ft 6 in (1.68 m) diameter – but there were several locomotives within the latter group that differed significantly from the others.

The "standard" variety of large-boiler C1 was represented by nos. 251, 272–291, 293–301, 1400–20 and 1422–51 built at Doncaster between 1902 and 1908. These had boilers producing saturated steam at a pressure of 175 lbf/in (1,210 kPa) and two outside cylinders, having a diameter of 18+ in (480 mm) and a stroke of 24 in (610 mm) using simple expansion driving the rear coupled wheels and fed through slide valves.