RETAILED BY LUND & BLOCKLEY, LONDON. LAST QUARTER 19TH CENTURY

Details

An unusual Redier's patent mahogany-cased mercurial registering barometer
Retailed by Lund & Blockley, London. Last quarter 19th Century
The case with glazed front door and hinged side panel, the inside mounted with a brass plaque inscribed REDIER'S PATENT REGISTERING BAROMEMETER/LUND & BLOCKLEY/42 PALL MALL/LONDON, with slide recording pencil and runner above a 14 in. long brass recording barrel with brass counter weight and driven by the main time movement with silvered platform to bimetallic lever balance, the glass siphon barometer tube (mercury removed) mounted on to the mahogany backboard and raised and lowered by fluctuations in barometric pressure by the mechanical servo-motor (in turn moving the recording pencil)
42 in. (107 cm.) high

Special notice

No VAT will be charged on the hammer price, but VAT at 15% will be added to the buyer's premium which is invoiced on a VAT inclusive basis.

Lot Essay

COMPARATIVE LITERATURE:
W.E. Knowles Middleton, The History of the Barometer, Trowbridge, 1994, p.325

Louis and Antonin Redier devised a series of barographs incorporating mechanical servo-systems. This particular system incorporates two mechanical motors. One is regulated by a platform lever escapement and is constantly raising the barometer tube at a greater rate than the mercury in the tube can fall. The other motor, which is not regulated by an escapement but governed by a fly, runs when released by a float on the mercury surface and allows the tube to descend twice as fast as the first motor can raise it. The motion of the tube is magnified and communicated to the recording pencil.

More from Important Clocks and Marine Chronometers

View All