scupper-hole

Another method of dealing with hands who could not keep their eyes open when on watch was to reeve a rope through the scupper-hole, attach one end to the person, and the other to a coal basket, which was thrown overboard.

The Shellback's Progress In the Nineteenth Century Walter Runciman 1892

He must have thought this fine sport, just as captains of fire engines love to point the tube of their hose; for he kept me running after him with full buckets of water, and sometimes chased a little chip all over the deck, with a continued flood, till at last he sent it flying out of a scupper-hole into the sea; when if he had only given me permission, I could have picked it up in a trice, and dropped it overboard without saying one word, and without wasting so much water.

Redburn. His First Voyage Herman Melville 1855