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Date: |
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Description: | ?Nederlandsche Marine?
?Pistor & Martins | Berlin | No 449?
The reflecting circle consists of a circular dark brown and yellow-lacquered brass frame, with two wooden handles. A third handle can be screwed in the back of the frame. The tangent screw, working against a spring-loaded stop, and the clamping screw are located at the bottom of the index arm. The instrument has four half-coloured shades, two red and one green. The index glass and horizon prism are non-adjustable.
Attached to the circle is a magnifier on a 135mm swivelling arm serving both verniers with a frosted glass shade. There is also a threaded telescope bracket in two parts, fitted for correcting collimation error. It has perpendicular adjustment made by a rising-piece and a milled knob. The telescope is 157 mm in length with an inverted image and two parallel cross wires. An extra drawtube is 113 mm long. Accompanying the instrument are a green shaded eyepiece, a rotating eyepiece with three red shades, and an adjusting pin. Several unidentified parts are missing.
The instrument has a polished brass limb with an inlaid silver scale indicated from 350� to 0� to 130� and from 160� to 260�, although the entire scale is divided by 10 arcminutes. The reflecting circle has two silver verniers measuring to 10 arcseconds, with the zeros in the centre.
The reflecting circle is contained in a square fitted mahogany box marked ?449?.
AUDIT - 6 parts need numbering. Inscription.
caption: Reflecting Circle - Front
caption: Reflecting Circle - Back
caption: Reflecting Circle - Inscription
caption: Reflecting Circle - Box
caption: unavailable | Publisher: | "http://collections.rmg.co.uk/" | Rights holder: | "Royal Museums Greenwich" | Subjects: | Reflecting circle Vernier reflecting circles | Source: | Royal Museums Greenwich | Identifier: | http://collections.rmg.co.uk/collections... | Go to resource |
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