South African Class 4 4-8-2

In 1911 the Cape Government Railways placed two steam locomotives with a 4-8-2 Mountain wheel arrangement in service. A year later, when they were assimilated into the South African Railways, they were renumbered and classified as Class 4.^[1][3][4]

Manufacturer

The first 4-8-2 Mountain type locomotive of the Cape Government Railways (CGR) was designed at the Salt River shops as a heavy mixed traffic locomotive by H.M. Beatty, the Chief Locomotive Superintendent of the CGR from 1896 to 1910. Two locomotives were built by North British Locomotive Company (NBL) and delivered in 1911. While they were numbered 850 and 851 in the CGR numbering series, they were not allocated a classification. A year later, when they were taken onto the South African Railways (SAR) roster, they were renumbered 1477 and 1478 and classified as Class 4.^[3][4][5]

Development

The locomotives were a further development of the two experimental locomotives that were placed in service by the CGR in 1906, the CGR Class 9 2-8-2 (SAR Class Experimental 5) and the CGR Class 10 4-8-0 (SAR Class Experimental 6), both built by Kitson and Company.^[6]

The Class 4 had bar frames, Stephenson valve gear with "D" valves and used saturated steam. The boiler was equipped with a combustion chamber, which reduced the distance between the tube plates to 18 feet (5.486 metres) and made them excellent steamers. The two locomotives were not identical, 1477 being equipped with Ramsbottom safety valves while 1478 had Cole’s muffled type Pop safety valves.^[1][4]

Service

Both of them were placed in service in the Karoo, working between Touws River and Beaufort West. In later years they were stationed at Worcester, from where they were used extensively on and around the Cape Western system’s main line, working pick-up goods trains to De Doorns in the Hex River valley and on the Mosselbaai line via Robertson.^[1][4]

They were withdrawn from service by 1938.^[4]

See also

• South African Class 4A 4-8-2
• Tender locomotive numbering and classification
• The 4-8-2 "Mountain"
• List of South African locomotive classes

References

1. ^ ^{a b c d e} Holland, D.F. (1972). Steam Locomotives of the South African Railways, Volume 2: 1910-1955 (1st ed.). Newton Abbott, Devon: David & Charles. pp. 12-13, 137. ISBN 0715354272. 
2. ^ North British Locomotive Company works list, compiled by Austrian locomotive historian Bernhard Schmeiser
3. ^ ^{a b c} Classification of S.A.R. Engines with Renumbering Lists, issued by the Chief Mechanical Engineer’s Office, Pretoria, January 1912, pp. 8, 12, 15, 46 (Reprinted in April 1987 by SATS Museum, R.3125-6/9/11-1000)
4. ^ ^{a b c d e} Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. pp. 38-39. ISBN 0869772112. 
5. ^ Holland, D.F. (1971). Steam Locomotives of the South African Railways, Volume 1: 1859-1910 (1st ed.). Newton Abbott, Devon: David & Charles. pp. 72-75. ISBN 0715353829. 
6. ^ Durrant, A E (1989). Twilight of South African Steam (1st ed.). Newton Abbott, London: David & Charles. p. 13. ISBN 0715386387.