GNR Class C1 (small boiler)

Specifications
Specifications
Configuration:;
• Whyte	4-4-2
• UIC	2′B1′n2s
Gauge	4 ft 8+1⁄2 in (1,435 mm) standard gauge
Leading dia.	3 ft 8 in (1.118 m)
Driver dia.	6 ft 8 in (2.032 m)
Trailing dia.	3 ft 8 in (1.118 m)
Loco weight	60.00 long tons (60.96 t; 67.20 short tons)
Fuel type	Coal
Water cap.	3,670 imp gal (16,700 L; 4,410 US gal)
Boiler pressure	170 psi (1.2 MPa) (saturated); 160 psi (1.1 MPa) (superheated)
Cylinders	Two, outside (3271: inside)
Cylinder size	18.75 in × 24 in (476 mm × 610 mm) (Saturated); 19 in × 24 in (483 mm × 610 mm) (Superheated)
Valve gear	Stephenson

Type and origin
Type and origin
Power type	Steam
Designer	Henry Ivatt
Builder	Doncaster Works
Serial number	769, 872–881, 974, 996–1003, 1005–1006
Build date	1898–1903
Total produced	22

Great Northern Railway small boiler class C1
London & North Eastern Railway class C2
Great Northern Railway small boiler class C1; London & North Eastern Railway class C2
	The first Atlantic tender locomotive in Great Britain, 990 Henry Oakley is preserved at York.
Power type
Type and origin
Power type	Steam
Designer	Henry Ivatt
Builder	Doncaster Works
Serial number	769, 872–881, 974, 996–1003, 1005–1006
Build date	1898–1903
Total produced	22
Configuration:;
Specifications
Configuration:;
• Whyte	4-4-2
• UIC	2′B1′n2s
Gauge	4 ft 8+1⁄2 in (1,435 mm) standard gauge
Leading dia.	3 ft 8 in (1.118 m)
Driver dia.	6 ft 8 in (2.032 m)
Trailing dia.	3 ft 8 in (1.118 m)
Loco weight	60.00 long tons (60.96 t; 67.20 short tons)
Fuel type	Coal
Water cap.	3,670 imp gal (16,700 L; 4,410 US gal)
Boiler pressure	170 psi (1.2 MPa) (saturated); 160 psi (1.1 MPa) (superheated)
Cylinders	Two, outside (3271: inside)
Cylinder size	18.75 in × 24 in (476 mm × 610 mm) (Saturated); 19 in × 24 in (483 mm × 610 mm) (Superheated)
Valve gear	Stephenson
Tractive effort
Performance figures
Tractive effort	15,240 lbf (67.8 kN) (Saturated); 14,728 lbf (65.5 kN) (Superheated)
Operators
Career
Operators	Great Northern Railway; London and North Eastern Railway;
Numbers	GNR: 250, 252–260, 271, 949–950, 982–990
Nicknames	Klondyke
Withdrawn	1935–1946
Preserved	990 Henry Oakley
Disposition	One preserved, remainder scrapped

The Great Northern Railway (GNR) Small Boiler Class C1 is a class of steam locomotive, the first 4-4-2 or Atlantic type in Great Britain. They were designed by Henry Ivatt in 1897. In total 22 were built between 1898 and 1903 at Doncaster Works. The class were commonly known as 'Klondykes' [sic], after the 1897 Klondike gold rush. They could reach speeds of up to 90 mph (145 km/h). They were also known as Small Atlantics.