Free Pendulum Clock, William Shortt Synchronome Co, London, 1925
Record status
Individual type · partial
Period
circa 1925
Impulse clock designed and built by William Hamilton Shortt, in association with the Synchronome Co, London, 1925. About 100 Shortt impulse clocks were made and used in observatories around the world. Shortt no. 5 was installed in the Melbourne Observatory in 1925, to run the Melbourne Observatory time service.
It was transferred to the P.M.G. (Post-Master General) Research Laboratories in 1945, which took over Victoria's civil time service, and in 1955 transferred to the P.M.G. in South Australia, where it was used until 1968. The clock comprises a free pendulum in an evacuated brass cylinder, and a slave pendulum in a Syncrhonome clock. The two pendulums swing together in precise sympathy, using a hit-and-miss synchronizer, so that the slave clock accomplishes the release of the gravity arm of the master clock and gives an impulse to the free pendulum.
Evidence at a glance
- Linked sources
- 1
- Photograph views
- 4
- Catalogue references
- 0
Counts describe this entry’s documentation, not authenticity, rarity or completeness. Photographs may show one specimen; check each caption and licence.
Physical characteristics
- Material
- brass
- Dimensions
- Overall Dimensions: 20 cm (Length), 40 cm (Width), 140 cm (Height)
Technical characteristics
- Maker recorded
- Synchronome Co Ltd; Shortt, William Hamilton
- Place recorded
- England, Great Britain
Identification
- Source note
- Transcribed from the Museums Victoria, Melbourne collection record for this single object (sentences kept verbatim apart from removed sale or rarity wording); how far it represents a wider collectible type has not been independently verified.
- Candidate id
- mv-407878
- Museum object name
- Free Pendulum Clock - William Shortt & Synchronome Co, Impulse Type, No.5, London, England, 1925
- Holding institution
- Museums Victoria, Melbourne
- Museum object number
- ST 28899
- Published references
- F. Hope-Jones, Electrical Timekeeping, 1940.
Catalogue references
No catalogue numbers recorded. Numbers are only published once transcribed from a verified edition of a standard catalogue — they are never inferred.
Research required
- Research required: confirm the wider type, maker and dating against a specialist reference; this entry documents one recorded example.