Compensation balance with Poole's auxiliary

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Compensation balance with Poole's auxiliary
Manufacturer	(unknown)
Production years	19th century
Production location	England

Balance with Poole’s auxiliary compensation. A discontinuous compensation for use with a steel balance-spring.

John Poole was one of London's best known chronometer makers and he had won prize medals at the 1855 Paris and 1862 London International Exhibitions. He also won a gold medal at the 1867 Paris International Exhibition. Tony Mercer in his book 'Chronometer Makers of the World' suggests the last known number of a chronometer produced by John Poole was number 3970. After his suicide his company was taken over by his brother James who continued to produce chronometers engraved with his brother's name.

[edit] How it works

Each short fixed arm carries a screw which at normal temperatures just touches the outside of the bi-metallic arms at a point about ¼ in. form the fixed end of the latter. At lower temperatures only the arc of the bi-metallic arm beyond this crew can move outwards; at higher temperatures the whole of the arm from its fixed end moves inwards, giving a greater movement of the weight for a given change of temperature.

[edit] Memories

Do you remember stories about clocks? Add your memories.

[edit] In the Science Museum's Records

Inv. No: 1929-70