850 Class
The GWR 850 Class was a long-running series of 0-6-0 saddle-tank shunting and short-distance goods locomotives designed by George Armstrong at Wolverhampton Works and introduced in 1874. Armstrong, who was responsible for the GWR's northern division works at Wolverhampton, produced the 850 Class as a practical and economical workhorse for yard shunting, short goods trips, and light branch work across the GWR system.
The basic configuration was simple and robust: inside cylinders, six coupled wheels of 4 ft 1 in diameter giving good adhesion for shunting and slow-speed goods haulage, and a saddle tank wrapping over the top of the boiler — the tank design that characterised GWR small tank engines before the subsequent widespread conversion to the panniers hung on the side of the boiler. Wolverhampton produced the class over an extended period, and the basic type proved sufficiently successful that it directly influenced the development of the later pannier tank variants that became ubiquitous across the GWR and its successors.
The 850 Class is historically significant as an early step in a design lineage that eventually produced hundreds of GWR pannier tanks in various sub-classes — one of the most numerous and long-lived locomotive families in British railway history. None of the original 850 Class saddle tanks was preserved, but the pannier tank descendants they inspired are well represented in preservation.
Design and development
George Armstrong designed the 850 Class at Wolverhampton Works in 1874 as a practical shunting and light goods engine for the GWR northern division. The 0-6-0ST configuration with 4 ft 1 in coupled wheels and a saddle tank over the boiler was a straightforward and reliable layout well suited to slow-speed yard and branch work. The design directly influenced the subsequent development of the GWR pannier tank variants, which replaced the saddle tank arrangement with panniers hung on the boiler sides.
Service and withdrawals
The 850 Class entered service in 1874 and worked GWR yard shunting and light goods duties for many years. The saddle tank configuration was progressively superseded by the pannier arrangement on later GWR tank classes. None of the original 850 Class was preserved, but the pannier tanks they helped inspire survive in significant numbers in preservation.
Identification features
Inside-cylinder 0-6-0 with saddle tank over the boiler, 4 ft 1 in coupled wheels.
Notable locomotives
- Various — the design evolved into the pannier tanks
Allocations and regions
Distributed across the GWR system for yard shunting, short goods trips, and light branch duties from 1874, concentrated particularly on the northern division served from Wolverhampton Works.