This particular component of a ship's log is called a log-ship or a log-chip. Thrown into the water astern of the moving ship, the log-ship's weighted hanging flap provided enough resistance to pull the log line off the reel. When the line was checked, at the end of a set time, the log-line pulled out of the notch near the fish's tail, and the log-ship could be recovered easily, head-first. This type of log was in use from the mid-sixteenth century until the twentieth century.
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