E Deck Features

Along the length of Scotland Road, the plans show several "Portable Plate for Shipping Furnaces" located at intervals down the corridor. What were these?

Also, a number of second class cabins (for example, E100, E103, etc.) have an odd, criss-crossed feature just inboard of the porthole - what were these?

1677784257696.pngPortable Plate.png

I read something about these very recently - apparently they could be removed to allow heavy machinery items to be moved into/out of the boiler rooms for repair/maintenance. Thread's here somewhere but I can't remember where! Sorry - can't help with the other question...
See post #57. Might be the one you referred too. Cheers