Accession No
6273
Brief Description
pair of parabolic mirrors for sound experiments, French or German, circa 1840
Origin
France or Germany
Maker
Class
sound
Earliest Date
1840
Latest Date
1840
Inscription Date
Material
metal (brass, white metal, steel); wood; glass; ceramic
Dimensions
height 910mm; base diameter 315mm; mirror diameter 420mm
Special Collection
Provenance
Purchased from Peter Delehar, 146 Portobello Road, London, England, before 1998.
Inscription
Description Notes
Both mirrors (6273.1, 6273.2) have a turned wooden base supports turned wooden pillar; whose height is adjustable by means of a wooden screw partway up the pillar. Hinged to the top of the pillar is a brass shaft which carries the brass parabolic mirror.
6273.1 has a horizontal brass bar attached to the pillar, length adjustable. The end of this bar carries a vertical brass shaft with a hook at the bottom end. A stopwatch (presumably later) hangs from the hook: white metal case with glazed ceramic dial; main minute dial with smaller inset seconds dial.
Condition good; complete.
References
Torben Rees; 'Parabolic sound mirrors: to reflect and focus sound'; Explore Whipple Collections online article; Whipple Museum of the History of Science; University of Cambridge; 2009: https://www.whipplemuseum.cam.ac.uk/explore-whipple-collections/acoustics/parabolic-sound-mirrors
Events
FM:43693
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