Traverse Board

The traverse board is used to keep track of changes in a vessel's speed or course over the period of a four-hour watch. At the end of each watch, the courses and speeds are added together, with the help of traverse tables, or by estimation, and marked in the logbook or on a chalkboard. A peg is put into a hole every half hour for the course steered, and another is inserted to reflect the approximate speed sailed. The traverse board, though used some in the sixteenth century, was more common in the seventeenth century.