
Movements & Components · Pendulum clock; magnetic star-wheel escapement
Eight-day pendulum table clock with star-wheel magnetic escapement, in perspex case, 1947-1949
- Maker / attribution
- Horstmann Clifford Magnetics Ltd. (maker)
- Date
- 1947-1949
- Historical period
- Modern Mechanical Horology (1945 – 1969)
- Country of origin
- England
- Place
- Bath, Bath and North East Somerset, England, United Kingdom, Bath
- Object type
- Pendulum clock; magnetic star-wheel escapement
- Holding institution
- Science Museum Group, London
- Accession / object no.
- 1949-114/4
- Credit line
- Horstmann Clifford Magnetics Ltd.
- Catalogue title (original)
- Eight-day pendulum table clock, 1947-1949
Record summary
Held and catalogued by Science Museum Group, London (object number 1949-114/4), this is a pendulum clock; magnetic star-wheel escapement by Horstmann Clifford Magnetics Ltd., made in Bath, Bath and North East Somerset, England, United Kingdom, Bath, dated 1947-1949. The Atlas places it in the Modern Mechanical Horology period (1945 – 1969) 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
The source record does not include a narrative description. The structured fields above are reproduced from it.
Historical context
Modern Mechanical Horology (1945 – 1969)
Tool watches for divers, pilots and astronauts; electric watches anticipate the electronic age.
Automatic winding, shock protection (Incabloc), and high-beat movements; electric and tuning-fork movements appeared.
Read the period in the timelineMore movements & components from this periodEarlier: Golden Age of Mechanical Watchmaking
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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