E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Hatches.
Put on the hatches. Figuratively, shut the door. (Anglo-Saxon, hæc, a gate. Compare haca, a bar or bolt.)
1
Under hatches. Dead and buried. The hatches of a ship are the coverings over the hatchways (or openings in the deck of a vessel) to allow of cargo, etc., being easily discharged.