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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