Garratt articulated locomotives were used by railway companies in such diverse places as Boma on the Congo River and the Cóndor railway station on the Rio Mulatos-Potosí line in Bolivia. This type of locomotive takes its name from its inventor Herbert William Garratt.
Herbert William Garratt was born in 1864. He served an apprenticeship at the North London Railway Bow works from 1879-1882. He moved to William Doxford and Son’s marine engineering works in Sunderland, later becoming an inspector for Sir Charles Fox and Sir Alexander Rendel. Garratt transferred to the Argentine Central Railway in 1889, where he became Locomotive Superintendent in 1892. Between 1900 and 1906 he worked for railways in Cuba, Lagos (Government Railway), and the Peru (Lima Railway). He returned to England in 1906.
Garratt was inspecting articulated vehicles for heavy artillery when it occurred to him that locomotives could be built in the same way. By 1907 he had developed the idea enough to apply for and be granted a patent. The locomotives are made up of three separate frames; the boiler frame, which carries the boiler and cab, is pivoted between two steam engines mounted on separate frames. Both power units carry water tanks, whilst the rear power unit also carries the fuel supply.
Garratt did not have the financial means to develop his idea therefore he had to tout it around locomotive works in the United Kingdom. Nobody was interested until he had the good luck to be at Beyer, Peacock and Company when they had an enquiry for a locomotive to run on the North East Dundas Tramway in Tasmania. This line already had a semi-articulated locomotive, a Hagans 2-6-4-0T. Garratt’s concept managed to interest the company and his new and untried design was submitted to Tasmania.
An order subsequently arrived from Australia and the drawing office had to produce a design for production. These first two Garratts (class K1) were unlike any Garratts built since. They had their cylinders on the inner ends of the bogies, with compound expansion and the low-pressure cylinders being on the leading units. A Garratt K1 locomotive is currently being preserved by the Welsh Highland Railway Society.
Soon after an engine order was received for the Darjeeling Himalaya Railway, this railway had 2 foot gauge track. Now the real prototype Garratt was produced: with simple-expansion cylinders positioned on the outer ends of the power bogies.
Garratt locomotives are able to carry much larger boiler units than conventional locomotives. They are also more flexible and can travel around tighter curves than conventional locomotives. For these reasons they have been used on railways throughout the world, particularly on narrow gauge track. The major disadvantage of a Garratt is that the adhesive weight decreases as the water is used from the front tank and coal from the rear bunker. As the weight on the wheels decreases slipping can occur.
As well as producing the locomotives, Beyer, Peacock developed and marketed the design, licensing it to other builders. After the original Garratt patents expired in 1928 Beyer, Peacock continued to market Garratts under the name Beyer-Garratt. With continuing development and patent improvements Beyer, Peacock maintained the Garratt concept. Just under two-thirds of all Garratt locomotives were built at their Gorton Foundry: the remainder were constructed by a number of licensees and a small number by non-licensed builders.
The final Garratts made to a Beyer, Peacock design were built in 1968. In Argentina Garratt’s are still being used on the Southern Fuegian Railway, the Train of the End of the World is a heritage railway into the Tierra del Fuego National Park considered, the southernmost functioning railway in the world.
Sadly, Garratt died in 1913 at the age of forty-nine so he was not able to see the international career of the locomotives bearing his name.