Battenberg's course indicator Mark III.

Battenberg's course indicator Mark III. © National Maritime Museum, London

Repro ID: D9249

Description: Station, speed and distance indicators were developed from the mid-19th century. With the introduction of fast steam ships, it became more important to be able to calculate the course and speed of other vessels within sight. This device, made by Elliot Brothers Ltd of London, was developed by Prince Louis of Battenburg, First Sea Lord at the outbreak of World War I. The outer edge is marked in compass points and degrees. The guide's bar, with the large pointer, is set to the compass course of the guide ship. The bar pivoted at the centre of the small circle has a scale for speed and the other two bars have scales for distance. The device proved especially useful in wartime convoys, for maintaining station on another ship.

Creator: Elliot Brothers Ltd

Date: c. 1925

Credit line: National Maritime Museum, London