South African Class 7B 4-8-0

In 1900 the Imperial Military Railways placed twenty-five Cape Class 7 4-8-0 Mastodon steam locomotives in service. In that same year, three Cape Class 7 locomotives that had been ordered by the Pretoria-Pietersburg Railway were also placed in service. All these locomotives were taken on to the Central South African Railways roster at the end of the Second Freedom War in 1902. In 1906 three of these locomotives were sold to the Natal Government Railways.^[2][3][7]

In 1912 twenty-six of these twenty-eight locomotives were assimilated into the South African Railways. They were followed in 1913 by the remaining two, that had been leased to Paulings. All but one of these locomotives were renumbered and reclassified to Class 7B. In 1915 one more Cape Class 7 locomotive was obtained from the Rhodesian Railways and erroneously also classified as Class 7B.^[2][3][6][7]

Background

After the outbreak of the Second Freedom War in 1899, control of all railways in the Cape and Natal Colonies remained in the hands of their civil staff, but now working in co-operation with the invading British military. As possession was obtained of the lines of the Orange Free State and the Zuid-Afrikaansche Republiek, the Oranje-Vrijstaat Gouvernementspoorwegen (OVGS) and the Nederlandsche-Zuid-Afrikaansche Spoorwegmaatschappij (NZASM) were combined into the Imperial Military Railways (IMR), in the hands of military and civilian staff appointed by the Director of Railways for the South African Field Forces, Lieutenant-colonel E.G.C. Girouard, KCMG, DSO, RE.^[2]

Manufacturer

Because of the damage caused during hostilities and the demands of the armed forces, a shortage of locomotives developed. In 1900 the IMR placed an order with Neilson, Reid and Company for twenty-five Cape Class 7 locomotives, which were numbered IMR 106 to 130 upon delivery.^[2]

Also in 1900, three Cape Class 7 locomotives that had been ordered by the Pretoria-Pietersburg Railway (PPR) were placed in service, also built by Neilson, Reid. Numbered PPR 7 to 9, these were the last locomotives to be obtained by the PPR before it ceased to exist upon its incorporation into the NZASM, which itself was subsequently incorporated into the IMR.^[2]

One more locomotive in the group that was eventually to become the South African Railways (SAR) Class 7B, was part of a batch of Cape Class 7 locomotives that was built for the Rhodesian Railways (RR) by Neilson, Reid in 1899 and placed in service in 1900.^[2]

All these locomotives were built to the same design as the 1896 to 1898 batch of Class 7 of the Cape Government Railways (CGR), later to become SAR Class 7A, with its increased heating capacity and Type ZE bogie-wheeled tenders.^[2]

Transfers and renumberings

After the cessation of hostilities on 1 June 1902, the IMR was transferred to civil control on 1 July 1902 and renamed the Central South African Railways (CSAR). The IMR and PPR Class 7 locomotives were renumbered CSAR 373 to 397 and CSAR 398 to 400 respectively.^[2]

In 1906 three of these locomotives, CSAR 384, 389 and 393, were sold to the Natal Government Railways (NGR) to work on the Harrismith-Bethlehem section in the Orange River Colony (ORC). They were renumbered NGR 327 to 329.^[2]

SAR classification

When all of these locomotives, with three exceptions, were assimilated into the newly established SAR in 1912, they were renumbered SAR 1032 to 1034, 1036 to 1039 and 1041 to 1058 and reclassified to Class 7B.^[2][3][6]

The first two exceptions, ex IMR 106 and 113, later CSAR 376 and 383 respectively, had been leased to Pauling and Company in 1911 for use on a construction contract and were only returned to the SAR in January 1913. They then received the numbers 1035 and 1040 respectively, which had been reserved for them even though the numbers were not listed in the 1912 renumbering tables.^[2][3][6][8]

Classification errors

Two locomotives that returned to South Africa from Rhodesia circa 1915, were both incorrectly classified, possibly as a result of their records getting exchanged in an apparent administrative error.^[2]

• IMR 110, the third exception mentioned above, would have become CSAR 380 in 1902, but never did since it had already been transferred, as replacement for a damaged locomotive, to the Beira and Mashonaland and Rhodesia Railways (BMR) at Umtali in March 1901, where it was renumbered to MR 19. When it was eventually sold back to South Africa and was taken onto the SAR roster in 1915, it was incorrectly classified as a Class 7D instead of a 7B and was renumbered 1355.^[2][5]
• In 1915 the sole ex RR locomotive mentioned earlier was brought onto the SAR’s Class 7B roster as SAR 949. It had started its service life as RR 1 and was renumbered twice. In the 1901 Rhodesian renumbering it was renumbered to MR 8 on the BMR. In the 1906 Rhodesian renumbering it was renumbered again, this time to 63 on the Rhodesia Railways Northern Extensions (RRM, operating north and east of Bulawayo). This locomotive was part of the same batch of ex RR locomotives that became SAR Class 7D and it was therefore incorrectly classified as a Class 7B.^[5][9]

The table shows all these renumberings except the multiple Rhodesian renumberings of SAR 949, as well as the builder’s works numbers.^[1][2][3][6]

Class 7 sub-classes

Other Class 7 locomotives that came onto the SAR roster from the Colonial and other railways in the region, namely the CGR, the NGR, some from the RR and, in 1925, from the New Cape Central Railways (NCCR), were grouped into six different sub-classes by the SAR, becoming SAR Classes 7, 7A and 7C to 7F.^[4][6]

Modifications

During their CSAR days, many of these locomotives were equipped with larger cabs and one, CSAR 381, later SAR 1058, was reboilered. The reboilered locomotive was reportedly also equipped with Drummond tubes in its firebox, but according to a note on a published dimensional drawing of the "Class 7B reboilered, CSAR", these were found to be unsatifactory and were soon removed.^[5][7]

During the 1930s many of the Class 7 series locomotives were equipped with superheated boilers and piston valves. On the Class 7C this conversion was sometimes indicated with an "S" suffix to the class number on the locomotive number plates, but on the rest of the Class 7 family this distinction was rarely applied. The superheated versions could be identified by the position of the chimney on the smokebox, with the chimney displaced forward to provide space behind it in the smokebox for the superheater header.^[4][6][7]

Service

Government railways

In SAR service, the Class 7 series worked on every system in the country. During the South West African Campaign in World War I twenty-nine Class 7 series locomotives were sent to South West Africa (SWA) to assist the expeditionary forces. Five of these were Class 7B locomotives, numbers 1042 to 1044, 1051 and 1052.^[5][7]

They proved so successful in that territory that more were gradually transferred there in later years. By the time the Class 24 arrived in SWA in 1949, there were still fifty-three Class 7 series locomotives in use there. Most remained there and were only transferred back to South Africa when the Class 32-000 diesel-electric locomotives replaced them in 1961. In South Africa they remained in branch line service, particularly at Tarkastad and Ladysmith and also on the line from Touws River to Ladismith, until they were finally withdrawn in 1972.^[7]

Industrial

In 1966 two Class 7B locomotives, numbers 1037 and 1040, as well as two Class 7 and four Class 7A locomotives were sold to the Zambesi Saw Mills (ZSM) in Northern Rhodesia (Zambia). The company worked the teak forests that stretched 100 miles (160 kilometres) to the northwest of Livingstone in Northern Rhodesia and it built one of the longest logging railways in the world to serve its sawmill at Mulobezi. These eight locomotives joined eight ex RR Class 7 locomotives that had been acquired by the ZSM between 1925 and 1956.^[5]

Railway operations ceased at Mulobezi around 1972, whilst operation of the line to Livingstone was taken over by the Zambia Railways in 1973. While most of the Class 7 series locomotives remained at Mulobezi out of use, Class 7A 1021 and Class 7B 1040 were installed at the Livingstone factory to supply steam for curing wood. Number 1040 was still in use in October 1995, when it was found in steam.^[9]

Gallery

The main picture shows SAR Class 7B 1056 (ex IMR 123, ex CSAR 389, ex NGR 328) at Voorbaai, Mosselbaai, on 4 September 1997.

See also

• South African Class 7 4-8-0
• South African Class 7A 4-8-0
• South African Class 7C 4-8-0
• South African Class 7D 4-8-0
• South African Class 7E 4-8-0
• South African Class 7F 4-8-0
• Tender locomotive numbering and classification
• The 4-8-0 "Mastodon"
• List of South African locomotive classes

References

1. ^ ^{a b c} Neilson, Reid works list, compiled by Austrian locomotive historian Bernhard Schmeiser
2. ^ ^{a b c d e f g h i j k l m n o p q} Holland, D.F. (1971). Steam Locomotives of the South African Railways, Volume 1: 1859-1910 (1st ed.). Newton Abbott, Devon: David & Charles. pp. 105, 122-124, 126. ISBN 0715353829. 
3. ^ ^{a b c d e f g} Holland, D.F. (1972). Steam Locomotives of the South African Railways, Volume 2: 1910-1955 (1st ed.). Newton Abbott, Devon: David & Charles. pp. 32, 139. ISBN 0715354272. 
4. ^ ^{a b c} South African Railways and Harbours Locomotive Diagram Book, 2’0” & 3’6” Gauge Steam Locomotives, 15 August 1941, as amended
5. ^ ^{a b c d e f} Pattison, R.G. (1997). The Cape Seventh Class Locomotives (1st ed.). Kenilworth, Cape Town: The Railway History Group. pp. 12-15, 24-32, 38-39, 56. ISBN 0958400946. 
6. ^ ^{a b c d e f g} Classification of S.A.R. Engines with Renumbering Lists, issued by the Chief Mechanical Engineer’s Office, Pretoria, January 1912, pp. 8, 12, 15, 39 (Reprinted in April 1987 by SATS Museum, R.3125-6/9/11-1000)
7. ^ ^{a b c d e f g} Paxton, Leith; Bourne, David (1985). Locomotives of the South African Railways (1st ed.). Cape Town: Struik. pp. 46-48. ISBN 0869772112. 
8. ^ Information supplied by John N. Middleton
9. ^ ^{a b} Pattison, R.G. (2005). Thundering Smoke, (1st ed.). Sable Publishing House. pp. 42-48. ISBN 0-9549488-1-5