Accession No
2625
Brief Description
harpoon ship log with line, by T. Walker, English, 1865 (c)
Origin
England; London
Maker
T. Walker
Class
navigation
Earliest Date
1865
Latest Date
1865
Inscription Date
Material
metal (brass); enamel; rope
Dimensions
length 545mm; breadth 135mm; height 160mm
Special Collection
Provenance
Purchased from Sotheby’s Belgravia, London, England; lot 206, 18/07/1980.
Inscription
‘T. WALKER’S
PATENT
HARPOON
SHIP LOG
A.2.
London’
Description Notes
Walker’s harpoon log. Brass casing and fins. Brass cover with aperture rotates to reveal white enamel plate with inscription with three dials with brass indexes, recording 1 mile, 10 miles and 100 miles. Length of rope attached to ring.
References
Joshua Nall; ‘Navigational Arts’; Explore Whipple Collections online article; Whipple Museum of the History of Science; University of Cambridge; 2020: https://www.whipplemuseum.cam.ac.uk/explore-whipple-collections/astronomy-and-empire/navigational-arts
Events
Description
This is a simple method of measuring a ship’s speed through the water. One end of the line is tied to the ship’s rail, the exact time is noted, and the brass ‘harpoon’ or impeller is thrown into the water. As it is towed along, the impeller rotates, the rotations being registered on three dials. After a certain number of minutes the harpoon is brought in, and the reading taken. The ship’s speed is calculated from distance covered, divided by the elapsed time.
04/08/2008
Created by: Dr Anita McConnell on 04/08/2008
FM:44390
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