What is a piece of timber running the whole length of a vessel inside the timberheads. D. Kemp. To lay on the shelf, to lay aside as unnecessary or useless; to dismiss; to discard called?

shelf — (Naut.) A piece of timber running the whole length of a vessel inside the timberheads. D. Kemp. To lay on the shelf, to lay aside as unnecessary or useless; to dismiss; to discard. (Webster's 1913.)

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