Page 46 - Demo

MOVEMENT
The movement has typically brass plates with rare triple-divided front plate secured in Knibb’s usual fashion with long delicate latches for the ten ringed pillars. The going train has verge escapement and triple gut fusees and spring barrels; the strike trains flanking the going train operate on Knibb’s double- six hour regimen employing two countwheels; the calibrated quarter wheel with lifting pins and later steel cross-arm lever over to the later hour countwheel: The hours are struck on the larger bell, the quarters on the smaller bell. The back plate is exquisitely engraved with tulip heads amongst scrolling foliage and it is signed Joseph Knibb Londini Fecit in a downward curve. The movement is secured by means of turnscrews at the back of the dial and now also with two later steel bolts into bottom pillars.
DOUBLE-SIX HOUR STRIKING
Double-six hour striking was a method imported from the Continent. The first six hours are struck as normal. The clock then reverts to one blow at seven o’clock, through to six blows at twelve o’clock. This economical method uses only forty-two blows on the bell in a twelve hour period, as opposed to seventy-eight on a normal clock.
Ronald Lee (The Knibb Family Clockmakers, Manor House Press, 1964, p.112) writes of Joseph Knibb: “Of all makers Joseph was by far the most daring when it came to methods of striking the hours and subdivisions of the hour”.
PROVENANCE
Wetherfield Collection, No. 112
Christie’s, London, 5th July 2002, lot 88 – sold for £108,000
LITERATURE
Eric Bruton, The Wetherfield Collection of Clocks, NAG Press, 1981, p.86, pl. 21. Dr. John Taylor O.B.E., Horological Masterworks, AHS, 2003, pp.172-175
EXHIBITED
The Museum of the History of Science, Oxford, 2003 Exhibit No. 38
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