Prismatic reflecting circle with case.

Reflecting circle made by F.W. Breithaupt and Sohn, Kassel, Hessen, Germany, about 1870. Circular anodized brass frame, polished limb, a wooden handle. Signed on the index glass mount: F.W. Breithaupt & Sohn | Hessen Kassel. Inlaid silver scale from 0° to 140°, and twice from 180° to 80° every 20'. One index arm with a silver vernier at both ends, to 20", zeros at the right. The tangent screw, working against a spring-loaded stop, and the clamping screw are at the bottom of the index arm. Four half-coloured shades (two red, one green (broken), one missing); no horizon shades. Index-glass adjustment by screw; horizon prism without adjustment. Magnifier on a 120 mm swivelling arm serving both verniers, a frosted glass shade (missing). Threaded telescope bracket in two parts, fitted for correcting collimation error; perpendicular adjustment by rising-piece and a milled knob. Telescope (158 mm) inverted image, six parallel cross-wires and one at a right angle to them are engraved on a lens within the telescope; a rotating shaded eyepiece with choice of clear, green, red and blue. A prismatic eyepiece; some unidentified parts are missing. In a square fitted mahogany box containing a trade label for Breithaupt in Cassel and a MS list of contents.

Details

Category:
Astronomy
Object Number:
1876-997
Materials:
brass (copper, zinc alloy), glass, silver (metal) and wood (unidentified)
Measurements:
overall (estimate): 220 x 400 x 300 mm
type:
reflecting circle and instrument case
credit:
F W Breithaupt and Son

Parts

Case for prismatic reflecting circle.

Wooden case for hand held prismatic reflecting circle by F.W. Breithaupt & Sohn, Kassel, 10 inch diameter to design of Pistor & Martin.

Materials:
wood and complete
Object Number:
1876-997 Pt1
type:
instrument case
Image ©
The Board of Trustees of the Science Museum