This drawing shows the original starboard side square box boilers. On the right is a 3 furnace boiler and towards the stern are two smaller auxillary boilers. Chris Ramsey has discovered that the auxillary boilers had 2 furnaces each. On the port side were two more three furnace boilers.
Drawing reproduced by permission of Oxford University Press Australia from "The Royal Australian Navy", David Stevens. www.oup.com.au
The engines are to the left of the boilers with the engine room platform above. Stokers