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Date: |
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Description: | George Bradford, 99 The Minories, Londo
?Spencer, Browning & Rust, London?
The repeating circle consists of a circular polished brass frame, with a detached wooden handle. A detached U-shaped bracket holds a second handle. The index arm caries the index glass and the telescope arm carries the horizon glass. The tangent screws and clamping screws are located on the back of the index arm and on the back of the telescope arm at the objective end. The instrument has three detached shades, two red and one green, and two square detached red horizon shades. Index-glass adjustment is made by a screw and on the horizon-glass by a screw and a capstan screw.
Attached to the circle are two threaded telescope brackets with perpendicular adjustment made by a rising-piece and milled knobs on both. The telescope is 115 mm in length with an inverted image and two parallel cross wires. Accompanying the instrument is an adjusting pin and a magnifying glass, which is missing.
The instrument has a polished brass scale from 0� to 720� by 30 arcminutes. The repeating circle has two verniers measuring by 1 arcminute, with the zeros at the right.
The repeating circle is contained in a square fitted wooden box with a blank brass plate on the lid. The box is lined with green paper and contains in the lid a trade label for George Bradford, 99 The Minories, London (1817-51). There is also an unidentified London trade label over which a paper is stuck with the handwritten note ?Patent Reflecting-Circle?.
The U-shaped bracket was recommended by Mendoza Rios, and according to him first applied by Troughton.
Audit - object needs marking with its NAV number. Nine unnumberd parts. Inscription. In fitted wooden box containing; 1 wooden screw on handle, 1 `U' shaped brass bracket with wooden handle, 5 shades \&\ 1 tommy bar.
caption: Reflecting Circle - front
caption: Reflecting Circle - back
caption: Reflecting Circle - inscription
caption: Reflecting Circle - box
caption: Reflecting Circle - box label
caption: unavailable | Publisher: | "http://collections.rmg.co.uk/" | Rights holder: | "Royal Museums Greenwich" | Subjects: | Vernier reflecting circles | Source: | Royal Museums Greenwich | Identifier: | http://collections.rmg.co.uk/collections... | Go to resource |
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?G. Bradford. 99 Minories London?…
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