13 pounder on experimental mounting, 1924-5

Of this vehicle BT White, in British Tanks and Fighting Vehicles 1914-1945 states;

A contemporary of the Birch guns, although designed for lighter field pieces, was the Light Artillery Transporter built by Sir WG Armstrong, Whitworth & Co Ltd in 1924. This vehicle, which carried a 13 pr gun (although a 3.7 in howitzer could be substituted) had the engine - a 48hp AEC 4-cylinder type - at the rear and the gun mounted at the front. There was no armour protection for the crew, but the Transporter was designed to be inconspicuous to make it more suitable for close support work. Only the prototype of this experimental vehicle was built.