Pocket watch by Leroux, John, England, 1785 — view 1 of 4
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Pocket Watches · Watch; lever movement

Pocket watch by Leroux, John, England, 1785

DocumentedDocumented from the holding institution's catalogue record.
Maker / attribution
Leroux, John (maker)
Date
1785
Country of origin
England
Place
London, Greater London, England, United Kingdom, London
Object type
Watch; lever movement
Holding institution
Science Museum Group, London
Accession / object no.
L2015-3365
Credit line
Lent by the Worshipful Company of Clockmakers
Catalogue title (original)
Gold lever escapement watch by John Leroux

View the source record ↗

Record summary

Held and catalogued by Science Museum Group, London (object number L2015-3365), this is a watch; lever movement by Leroux, John, made in London, Greater London, England, United Kingdom, London, dated 1785. The Atlas places it in the Precision & Scientific Horology period (1750 – 1850) of its Pocket Watches collection. The record is illustrated with 4 photographs.

Assembled from the source record's structured fields. Dates and attributions are given as the source states them; where a field is missing the Atlas leaves it blank rather than estimating.

Catalogue description

Science Museum Group description

This is the earliest example of a watch with a lever escapement in the Clockmakers' Museum collection. The original detached lever escapement as devised by Thomas Mudge in the 1750’s, was developed and refined by a number of different watchmakers over the following century. It is still seen in many mechanical watches produced today, in the form of the Swiss lever escapement. Leroux’s escapement is thought to be the first to have incorporated draw; a safety feature designed into the escapement to prevent it from accidentally unlocking. This is one of only two known lever escapement watches by Leroux. Leroux became a Freeman of the Worshipful Company of Clockmakers in 1781. Clockmakers' Museum No. 454.

Historical context

Precision & Scientific Horology (1750 – 1850)

Harrison solves longitude; Mudge invents the lever; Breguet's Paris workshop defines the modern watch.

From 1750 to 1850 the watch became a precision instrument. Mudge's lever escapement, the cylinder escapement, Lépine's thin bar calibre, Breguet's innovations (overcoil, tourbillon, perpétuelle) and the pocket chronometer of Arnold and Earnshaw all date from this period, while verge watches remained common in cheaper production.

Read the period in the timelineMore pocket watches from this periodEarlier: Early Modern Horology

Atlas type guide

Pocket watches

The pocket watch was the dominant personal timekeeper from the late seventeenth century until the First World War. Its development tracks the history of the escapement: verge watches with fusees until the late eighteenth century; Thomas Mudge's lever escapement (c. 1755) and the cylinder escapement popularised by George Graham and later by Swiss makers; and the Swiss and English lever watches of the nineteenth century. Lépine's bar-bridge calibre and keyless winding made watches thinner and easier to use.

Industrialisation transformed the trade: American factories such as Waltham (from 1850) and Elgin produced interchangeable parts by machine, and Swiss makers responded with their own mechanisation after the 1876 Philadelphia Exhibition. By 1900 a reliable watch was affordable to millions; the finest makers continued to produce complications and precision watches.

What to look for

  • The escapement: verge (crown wheel), cylinder, duplex, English or Swiss lever.
  • Key winding (a square arbor in dial or back) or keyless crown winding.
  • Signatures and serial numbers on the movement, dial and inside case back.
  • Hallmarks, case maker's marks and gold or silver standards stamped in the case.
  • Dial material: enamel, silver, gold, later printed metal.

Dating clues

  • Verge watches dominate before c. 1800; cylinder watches c. 1770–1900; lever watches after c. 1820.
  • Keyless winding: increasingly common after c. 1860.
  • Manufacturer serial number lists exist for Waltham, Elgin, Longines, Omega, Patek Philippe and others.

General guidance written by the Atlas editors about this kind of object. It is not a statement about this particular piece; for that, rely on the source record above and on physical examination.

Read next:Verge escapementFuseeIdentification Centre

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