The Hunslet Geared Locomotive.
This narrow-gauge geared loco was built for use in Natal, South Africa, probably on tea plantations.
The engine is a V4, visible below the boiler. The chimney incorporates a spark-arrester. The thing on top of the front tank is a steam-turbine generator to power the front and rear lights.
Here are some nuggets of hard fact:
Four, 6.5in diam x 8in stroke
Delivered to Natal estates in 1931.