| It's so difficult to say without seeing any more of it but, yes it could be part of a "Fan Room" and the indent could be some sort of filter arrangement or moisture eliminators which could be made more effective by increasing the available surface area.
It could also be the Captains bathroom from what we can see of it!!
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“Dirty British coaster with a salt-caked smoke stack, Butting through the Channel in the mad March days" |