Astronomical alarm clock

Record summary

Held and catalogued by Royal Museums Greenwich (object number ZAA0525 ZAA0525 TA/AC4 D7113), this is an astronomical alarm clock, made in London, England, dated 1815. The Atlas places it in the Precision & Scientific Horology period (1750 – 1850) of its Clocks collection. Materials and techniques recorded by the source: Metal Metal Metal. Recorded dimensions: Overall: 310 x 265 x 170 mm. 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.

Atlas type guide

Alarm clocks

Alarm work is among the oldest clock functions: monastic clocks woke monks for night prayers, and Renaissance table clocks often carried an alarm disc set by a pin. A separate spring or weight is released at the set time and drives a hammer against a bell. Some early alarms also lit a candle by striking a flint — the 'tinder pistol' alarm.

The cheap, mass-produced alarm clock arrived in the second half of the nineteenth century. American firms such as Seth Thomas and Westclox (the 'Big Ben' of 1910) and German makers such as Junghans and Kienzle made millions of drum-shaped alarms with pin-pallet escapements. Electric, quartz and digital alarm clocks followed in the twentieth century.

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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