been a mystery to me for awhile but surely someone must know what it is. The handle screws down forcing the rubber washer to expand and seal the container, some kind of egg coddler device maybe?
It looks too complicated for a darning egg. Made in England Reg No------ Registration Number 73 Prov Pat ----Provisional Patent ?
It is hard to see how big it is, and whether it would be feasible for such use as Taupou suggests. It also seems a darning egg would not need such a fancy washer/sealing system. Is the egg shaped portion hollow, such that it could have held a liquid (either heated or chilled)?
I think it just has a registered design number, ive never had much luck getting any info from them only patent numbers on espace.net