A rather handsome old clockwork O-gauge 4-4-2 tank locomotive, complete with a rake of wagons - it sat on the shelf in my old office for a long time before I was evicted when we built the new photographic studio (it's alright, I've be rehomed into a new upstairs office now).
Can't find any maker's mark on it, no doubt one of our tinplate experts will identify who built it and when.