E J DENT ‘Watchmaker to the Queen’ London. No 9507

14147

£ 1,450.00

Rare early 'simple split-seconds' chronograph by this most famous maker.

More details

Silver engine-turned case with gold joints hallmarked 1846, casemaker AT (Alford Thickbroom, Clerkenwell). Fullplate fusee movement with cap jewels on balance (diamond) and escape, with balance-brake for setting exactly to time, and with Gougy's Patent 'simple split' chronograph work mounted under the dial. Single-roller detached lever escapement. Compensation balance, spiral balance-spring. Signed enamel dial with seconds at 12, having two hands, one of which can be stopped via a push in the pendant. 52.5 mm diameter.

The firm of E J Dent, Cockspur Street, and later at the Strand and Royal Exchange, London, one of the most important English watch, clock and chronometer makers of the second half of the 19th century. See the book on the various Dent firms by Vaudrey Mercer for more information, copies of which can usually be found on my website - these rare chronograph watches are not mentioned.


NB: These watches are a step towards Nicole's fully developed chronographs of post 1862, with start, stop and return to zero mechanism in addition to a watch train that continues to tell the time, ie, a true chronograph. Wikipedia and many other Swiss website references to the simple timer of Moinet being the first chronograph are, at best, being economical with the truth, made worse by the endorsement of the Guiness Book of Records ridiculous award! Nor did Rieussec or Winnerl invent the first chronograph - the work of Daniel Delander preceded this by around 100 years.


Pierre Frederick GOUGY, Patent 8308, December 1839. "The introduction into watches...of a supplementary second hand, so adjusted by mechanism that it may be stopped while the other second hand is going, and on being set free will recover its original position." Examples of this simple split-seconds mechanism are rare. The two seconds hands are connected by a spiral hairspring, the outer end of which is connected to a steel disc. Pushing on the pendant allows a sprung lever to stop the disc and thus one of the hands, and the time can be noted. Releasing the push allows the disc and thus the hand to catch up with the standard seconds hand, with which it then continues to revolve as one. 


If the push is held down, the standard seconds hand will continue to move but the spring joining the two will tighten until the watch is forced to stop. This is NOT how such watches were intended to be used. This mechanism should rightly be seen as an improvement on the earlier inking chronographs. At the start of an event the push is activated and the time noted, and the push then released. At the end of the event the push is again activated and the time noted, a quick subtraction giving the precise time taken - and all without having to remove ink marks from an otherwise fragile dial, not to mention the hands.


Repair to dial edge between 5 and 7, otherwise a fine, complete and original example of this rare chronograph variant.


Reserved

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