Hi Graham
I like this picture very much!
It is a very different and exciting composition
I'm guessing that the steam is coming from the blowdown valve..
(Or maybe some self cleaning smokebox design which is not familiar to us in England)
Best Wishes, and stay safe!!
Peter

Thanks Peter, this seems to be fitted to Queensland locos. It wasn't on the system I knew in New South Wales. I'll put some photos up after Saturday showing how it works.
It's taken a while to get a good photo of this in action.

Awesome shot!

Thanks William.

Lovely old beast!

Thanks Diana, I agree.