This is a C19th nutmeg grater. in the shape of the wine bottle of that period. The top pulls off to reveal the grater. There is storage for the nutmegs inside.
It has the original ebonised black finish to correspond to the black glass of the wine bottles in the 19th century.
These pocket nutmeg graters were popular, being carried around and when you bought mulled wine you could grate fresh nutmeg grater onto it.
It measures 10cm h x 4cm w.