Very early Ship’s Towing Log – Massey, London, 19th century
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.
Copies of this mechanical log can be found in the National Museum Greenwich and the Maritime Museum in Amsterdam. Four copies are described by Sharp. This shows that in the beginning there was a lot of experimentation with the design of the log. The specimen shown here is not described but is unmistakably from Massey. It appears to be an early variant, perhaps it is a prototype. The rotor has the characteristic design of Massey with cross connections between the blades. Log and rotor both have the same eye. However, the rotor has Walker’s anchor. Massey and Walker worked closely together in the development of the log. In 1861 Walker took over the production from Massey. The hands and the structure with swiveling cover have disappeared. Marked with PATENT LONDON.
Catalog: NM. 4-23
Date: 1802 – 1810
HWL: 5.4 x 15.5 x 30 cm
L rotor: 41 cm
Rotor signed: T.W. with anchor
Condition: good, structure with swivelling cover missing