Electric clock for the prototype Pegasus computer, (attached to central processing unit), made by Ferranti Ltd's London laboratory, c. 1956.

Record summary

Held and catalogued by Science Museum Group, London (object number Y1993.46), this is a mains electric wall clock by Ferranti Limited, made in United Kingdom, United Kingdom, dated 1956. The Atlas places it in the Modern Mechanical Horology period (1945 – 1969) of its Clocks collection. Recorded dimensions: Overall: 180 mm x 180 mm 180 mm. The record is illustrated with 2 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

The source record does not include a narrative description. The structured fields above are reproduced from it.

Atlas type guide

Regulators, wall and Vienna clocks

A regulator is a precision pendulum clock used as a time standard in observatories, workshops and railway offices. Typical features are a deadbeat or Graham escapement, a temperature-compensated pendulum (mercury jar, gridiron or later invar), maintaining power and a regulator dial that separates hours, minutes and seconds. George Graham's deadbeat escapement (c. 1715) and his mercury pendulum, together with Harrison's gridiron, set the pattern for two centuries.

Wall clocks span a much wider range: the elegant Viennese Laterndluhr and Dachluhr of the Biedermeier period, the Dutch stoelklok and staartklok, English 'dial' clocks used in schools, offices and railway stations, and mass-produced spring and weight wall clocks from Germany (Gustav Becker, Junghans, Kienzle) and America.

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.

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