5,310 CHF
“Early Keyless Winding, Universal Temperature Compensation” John Roger Arnold, London, Patent No. 132. The case by Thomas Hardy with London hallmarks for 1825. Very fine and rare, 18K gold, early keyless pocket watch with ruby cylinder escapement, early keyless winding system, and unusual temperature compensation . Five-body, “bassine et filets”, by Thomas Hardy (mastermark TH), engine-turned, reeded band. Hinged gold cuvette. Gold with engine-turned center and outer border, painted radial Roman numerals, subsidiary seconds. Blued steel "pear" hands, the minute hand secured by a screw. Gilt brass three-quarter plate with cylindrical pillars, free-standing barrel passing through the back plate and secured by a bridge, ruby cylinder escapement, plain polished steel three-arm flat-rim balance, flat blued steel balance spring with unusual bimetallic compensation curb on the index regulator, early Prest keyless winding system, patented in 1820. Movement signed. Diam. 52 mm. Notes In 1820, Thomas Prest obtained a patent No. 4501, for a keyless winding watch, it was described as follows: "A New and Additional Movement applied to a Watch, to enable it to be wound up by the pendant Knob without any Detached Key or Winder " John Roger Arnold therefore came to some arrangement with Thomas Prest and straightaway in 1820, they proceeded to produce a series of lovely watches with ruby cylinder escapements, going barrel, compensation curb, flat steel balance and the new Prest keyl
Auctioneer:
Antiquorum
Date:
2006-05-14
