What is "dredging box"

Dredger \Dredg"er\, n. (Cookery) A box with holes in its lid; -- used for sprinkling flour, as on meat or a breadboard; -- called also dredging box, drudger, and drudging box.

n. 1 A dredger (container with a perforated lid used for scattering sugar or flour). 2 (context military historical English) A copper box with a perforated lid, used for sprinkling meal powder over shell fuses.