Fowler steam traction engines emerged most successfully from War Office trials in 1899 for engines to be employed in the South African war. As a consequence, machines built by John Fowler & Co Ltd of Leeds represented by far the biggest proportion of the forty or so traction engines that were in South Africa by mid-1900.
The traction engines were used for pulling trains of supplies, alongside oxen or mule transport, or towing guns to different positions. For protection against attacks on supply columns by Boer raiding parties some armoured traction engines were ordered, and the first of these vehicles, together with four bullet-proof trucks, arrived in South Africa in July 1900, followed by a second train two weeks later.
The armoured engines were Fowler model B5s of 10 nhp (nominal horse-power) or 115 to 125 maximum ihp (indicated horse-power). The bullet-proof plates completely enclosed the body of the machine in a slab-sided structure, only the chimney projecting. At the front a hinged semicircular plate protected the lower part of the boiler, and at the rear the armour was extended out either side, partly over the driving wheels. Three loopholes for the use of the crew’s weapons were provided in each of these projections. Access to the vehicle was by means of a door through the armour at the rear. The armoured trucks which went with the Fowler B5s were four wheelers, the front axle, which incorporated the tow-bar, being mounted on a turntable. The armour on each side was in three sections, which could be hinged inwards independently. Each section carried a loophole. There was no overhead armour protection. A field gun could, by means of special channels, be hauled into a truck and carried, instead of being towed.
Four Fowler B5s were armoured; numbers 8894, 8895, 8898 and 8899. The first two armoured road trains were sent to Bloemfontein on arrival, where the armour was removed from both engines and trucks and used to make armoured railway trains. Towards the end of 1901 the General Officer commanding the Kimberley District asked for further trucks to be fitted with armour so that the troops needed for road-convoy escort duties could be reduced, and the War Office was requested to supply two armoured trucks. Remembering that the first two sent had been stripped of their armour to make armoured railway trains, it is not surprising that the War Office did not meet this request.
The gun-carrying truck, mentioned above, inspired Lieutenant-Colonel von Layriz, a prominent German military writer, to suggest that quick firing guns should be mounted on the wagons to act as a sort of mobile fort to protect bridges and other important points against flying columns of Boers. This idea was not adopted, but if it had it is interesting to speculate that it would have anticipated by many years some of the elements of the tank.
B T White. 1970. Tanks and Other Armoured Fighting Vehicles 1900 - 1918. Blandford Press Ltd, London, England.
A Polish company called JB Models (http://www.jbmodels.jb-art.eu/fowler.html) make a paper/card kit in 1/50 scale; currently it is available as a free download from their web site. Other than that lone example you will have to scratch build or convert one. There is an article in the model making section of this site on how to scratch build one. Matador Models and Matchbox/Corgi ("Models of Yesteryear") both have the unarmoured version of the Fowler engine in their ranges, which may make a suitable starting point for a conversion.