
Movements & Components · Weight-driven pendulum clocks; gravity escapements; turret clocks
Escapement model by E.Dent and Co.Ltd; Grimthorpe, Edmund Beckett, Baron, 1816-1905, England, 1939
- Maker / attribution
- E.Dent and Co.Ltd; Grimthorpe, Edmund Beckett, Baron, 1816-1905 (maker); E Dent & Company Limited (maker); Edmund Beckett Grimthorpe (maker)
- Date
- 1939
- Historical period
- Golden Age of Mechanical Watchmaking (1900 – 1945)
- Country of origin
- England
- Place
- London, London, Greater London, England, United Kingdom
- Object type
- Weight-driven pendulum clocks; gravity escapements; turret clocks
- Holding institution
- Science Museum Group, London
- Accession / object no.
- 1969-513
- Credit line
- E Dent & Company Limited
- Catalogue title (original)
- Three train, flatbed turret clock by E. Dent with double three-legged gravity escapement, c. 1939.
Record summary
Held and catalogued by Science Museum Group, London (object number 1969-513), this is a weight-driven pendulum clocks; gravity escapements; turret clocks by E.Dent and Co.Ltd; Grimthorpe, Edmund Beckett, Baron, 1816-1905, made in London, London, Greater London, England, United Kingdom, dated 1939. The Atlas places it in the Golden Age of Mechanical Watchmaking period (1900 – 1945) of its Movements & Components collection. The record is illustrated with 1 photograph.
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
Movement of a 3-train turret clock by E. Dent and Co., made about 1939; the going train has Grimthorpe's double 3-legged gravity escapement; the striking train and Westminster quarters are controlled by locking plates; with 1 1/2 second pendulum and double trestle frame for support.
Historical context
Golden Age of Mechanical Watchmaking (1900 – 1945)
The wristwatch displaces the pocket watch; waterproof cases, self-winding and grand complications.
Precision lever movements, electric clock mechanisms and new alloys (invar, elinvar) characterised the period.
Read the period in the timelineMore movements & components from this periodEarlier: Industrial Revolution
Atlas type guide
Escapements and escapement models
The escapement is the heart of every mechanical clock and watch: it releases the gear train one tooth at a time and gives small impulses to the oscillator (pendulum or balance) to keep it swinging. The verge (thirteenth century), anchor (c. 1670), deadbeat (c. 1715), cylinder (1720s), lever (c. 1755), detent (1780s) and co-axial (1970s) escapements each solved problems of friction, recoil and isochronism in different ways.
Large demonstration models of escapements were made for teaching in horological schools, for patent applications and for exhibitions. They are valuable because they make visible, at large scale, the minute interactions that take place in a watch many times per second.
What to look for
- The shape of the escape wheel teeth: crown wheel (verge), pointed (anchor), club-toothed (Swiss lever), ratchet (English lever), or two-tiered (co-axial).
- Pallets: flags on an arbor (verge), anchor-shaped, jewelled lever fork, or a detent spring.
- Whether impulse is given directly, through a lever, or in one direction only (detent).
- Teaching models usually carry the name of a school or demonstrator.
Dating clues
- Verge: c. 1275–1850.
- Anchor and deadbeat for clocks: after c. 1670 and c. 1715.
- Club-tooth Swiss lever: standard after c. 1880; co-axial in series from 1999.
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 escapementAnchor (recoil) escapementDetached lever escapementSpring detent escapementCo-axial escapementGrasshopper escapementEscapement simulation lab
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