Walker Patent A1 Harpoon Ship’s Log

1860’s Walker Patent A1 Harpoon Ship’s Log. Brass with enameled dial. Custom wooden display base included. Early model. Scarce. Marked #3709. Collector level patina.

Harpoon logs were dragged behind a ship to measure it's distance and speed. Daily/hourly speed and distance recordings could be taken to easily calculate the ship's overall travel. Propeller-powered, geared mechanical recording mechanism features 3 units of mile measures: 0 to 100 (in tens), 0 to 10 (in units), and 0 to 1 (in quarters). Fins feature an anchor and 'TW' (for Thomas Walker).

Though it's technology was incepted in 1699 by Robert Hooke, the first commercial patent was secured by Thomas Walker's uncle, Edward Massey in 1802. After Edward's retirement, Thomas Walker continued his uncle's work and went on to patent the Walker log, such as this, in 1861. 

Weight: 4 lbs. 11 oz. 

Dimensions: 20.00" x 6.00" x 5.00"

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