What is the gunwale of a ship. To lower the yards a-portoise, to lower them to the gunwale. -- To ride a portoise, to ride an anchor with the lower yards and topmasts struck or lowered, as in a gale of wind called?

portoise — The gunwale of a ship. To lower the yards a-portoise, to lower them to the gunwale. -- To ride a portoise, to ride an anchor with the lower yards and topmasts struck or lowered, as in a gale of wind. (Webster's 1913.)

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