It appears that I finally got something right !
On the Hellingly Hospital Railway, I have modelled the delivery of a set of boardroom chairs. In truth the scene was influenced by the purchase of a set of Springside whitemetal furniture rather than a deliberate attempt to recreate the prototype but that doesn't matter.
I decided that it would be unlikely that fine furniture would travel in a van without some sort of protection so the castings were wrapped in a bit of toilet paper and painted to represent hessian. The man peeking underneath makes the cameo for me and visitors to exhibitions seem to like it.
Anyway, it seems that the people at the GWR museum thought the same. On display in Steam is some furniture, and it's all wrapped up. Admittedly they have used brown paper but I suspect this might have been expediencey rather than absolute fidelity, however I assume they were working with some reliable information so we are both right.