Rare Harpoon log – Heath & CO, London
From the 17th century onwards people had made many attempts to devise a mechanical log which would automatically record the ships distance done. Edward Massey invented a mechanical log in 1802 with four blades which was used by the Admiralty from 1807-1815. When dragged behind the ship the log vins rotates and the revolutions were transformed in miles on the dials, to be read after the log was brought in. The design of Massey was further refined by Thomas Walker and Son, who took out a patent for the A1 Harpoon Log in 1861. Heath & Co., instrumentmakers in London from 1845-1910, made only a few harpoonlogs based on Walkers patent of 1861, also with stabilizer.
On the log there are three dials, the first registers dozens of miles up to 100, the second registers the units up to 10 mile, the third registers quarters of a mile.
Like all Heath harpoon logs, this one also has a little tolerance on the propulsion with the blades. Behind the blades there is damage to the floating body.
With original rope.
Date: 1860 – 1880
LD: 49,5x14cm (19,5×5,6 in)
HEATH & Co (LIMITED)
WALKER’S PATENT 1861
Condition: good and complete