Thought some of you may be interested in some photos that I have in an old edition Faber and Kell's I have.
Overview of the arena area, also showing the jet nozzles which are blue in photo 3.
Making a bit of an assumption but I would think that these cylinders are the other end of what you've got in photo 10. Potentially they were disused and replaced with the more modern looking one's in 15/16.
Some other photos of electrode boilers (I'd doubt that these are still there) and some schematics.
I'm not entirely sure of what is shown in photo's 15 and 16, the book I have mentions a series of Lancashire boilers, however I'm almost certain that these would of been removed and replaced with more modern equipment. They could be new thermal storage cylinders, but I'm not entirely sure.