The South African Railways Class 19C 4-8-2 of 1935 was a steam locomotive. In 1935, the South African Railways placed fifty Class 19C steam locomotives with a Mountain type wheel arrangement in service. It was the first South African locomotive class to use rotary cam poppet valve gear and also the first to be built new with a Watson Standard boiler. Manufacturer When the need for more branch line locomotives became apparent in 1934, tenders were invited by the South African Railways (SAR) for another fifty Class 19B locomotives with Walschaerts valve gear, but redesigned by Chief Mechanical Engineer A.G. Watson with his Watson Standard no. 1A boiler. When the tenders were received, it was found that the North British Locomotive Company of Glasgow, Scotland, had also tendered for a locomotive with rotary cam poppet valve gear as an alternative to Walschaerts valve gear. Even though this would increase the cost per locomotive by £200, Watson decided to accept this tender in view of the good reports he had received concerning poppet valve gear. This variation on the design led to these locomotives being designated Class 19C when they were delivered in 1935. Characteristics Tenders All fifty Class 19C loco­motives were erected at the Salt River shops and numbered in the range from 2435 to 2484, and many remained stationed at Cape Town while being subjected to exhaustive testing. As built, the Class 19C was delivered with Type MT tenders with a coal and a water capacity, even though the axle load of of these tenders exceeded the permissible limits on the branch lines for which the Class 19C was intended. Upon delivery, their new Type MT tenders were exchanged for the smaller modified Type MP1 tenders from some of the reboilered mainline locomotives. The Type MP1 had a lighter axle load of and was therefore more suitable for branch line work. This policy was followed with all the Classes 19B, 19C and 19D, except the last batch of Class 19D which was delivered with Type MX torpedo tenders. Watson Standard boilers Soon after A.G. Watson was appointment as CME in 1929, he set out on a program of standardisation of locomotive boilers and engine parts which ultimately led to a considerable reduction in the time taken for locomotive repairs. At the time, 88 different types of locomotive were in service, for which some fifty types of replacement boiler were