Nice maintenance photo.  I've never seen an A4 with the access hatch raised.
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The access doors to the smokebox were known as 'the cod's mouth'. The top half was opened by using a handle inserted in a hole on the far side of the locomotive and turned to operate a screw mechanism. The lower half was then lowered and retained by the chains you can see in the photograph.
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| Posted by  on February 24, 2025  |  |   
Very cool - neat to see this open. A special place for the mother-in-law to sit!
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