28th Apr, 2010 12:00
Maritime and Scientific Models, Instruments & Art (Undaunted)
166
[M] A MID-19TH-CENTURY DIPLEIDOSCOPE BY E.J....
A MID-19TH-CENTURY DIPLEIDOSCOPE BY E.J. DENT
heavily constructed in brass, the lid inscribed E.I. Dent's Patent Meridian Instrument / 82 Strand & 33 Cockspur St. LONDON -- 2½in. (6.5cm.) high
The dipleidoscope was patented in 1843 by James Bloxam and marketed by Edward Dent for timing the meridian transit of the sun. The mirror cell contains a hollow, right-angled prism, with two sides silvered and one of glass. The meridian transit was determined by the coincidence of two images of the sun by single and double reflection, one from the top glass and the other from both mirrors. With the base properly levelled and oriented, the meridian transit could be read to seconds.
Estimated at £200 - £400
heavily constructed in brass, the lid inscribed E.I. Dent's Patent Meridian Instrument / 82 Strand & 33 Cockspur St. LONDON -- 2½in. (6.5cm.) high
The dipleidoscope was patented in 1843 by James Bloxam and marketed by Edward Dent for timing the meridian transit of the sun. The mirror cell contains a hollow, right-angled prism, with two sides silvered and one of glass. The meridian transit was determined by the coincidence of two images of the sun by single and double reflection, one from the top glass and the other from both mirrors. With the base properly levelled and oriented, the meridian transit could be read to seconds.
A MID-19TH-CENTURY DIPLEIDOSCOPE BY E.J. DENT
heavily constructed in brass, the lid inscribed E.I. Dent's Patent Meridian Instrument / 82 Strand & 33 Cockspur St. LONDON -- 2½in. (6.5cm.) high
The dipleidoscope was patented in 1843 by James Bloxam and marketed by Edward Dent for timing the meridian transit of the sun. The mirror cell contains a hollow, right-angled prism, with two sides silvered and one of glass. The meridian transit was determined by the coincidence of two images of the sun by single and double reflection, one from the top glass and the other from both mirrors. With the base properly levelled and oriented, the meridian transit could be read to seconds.
heavily constructed in brass, the lid inscribed E.I. Dent's Patent Meridian Instrument / 82 Strand & 33 Cockspur St. LONDON -- 2½in. (6.5cm.) high
The dipleidoscope was patented in 1843 by James Bloxam and marketed by Edward Dent for timing the meridian transit of the sun. The mirror cell contains a hollow, right-angled prism, with two sides silvered and one of glass. The meridian transit was determined by the coincidence of two images of the sun by single and double reflection, one from the top glass and the other from both mirrors. With the base properly levelled and oriented, the meridian transit could be read to seconds.
Auction: Maritime and Scientific Models, Instruments & Art (Undaunted), 28th Apr, 2010
