Brass reflecting circle.

Reflecting circle made by Pistor and Martins, Berlin, Germany, about 1870. Black-lacquered brass disc with a bright brass limb, the handle is missing. Signed on the limb: Pistor & Martins Berlin. Marked on the limb: 806. Marked on the knob fixed of the magnifier's arm: KM. | 5. (for Kaiserliche Marine, see notes). Inlaid silver scale indicating from 350° to 0° to 130° and from 180° to 240°; the entire scale is divided every 20' (digits engraved in the brass limb). Two silver verniers to 20", zeros at the right, at either end of the index arm. The tangent screw (missing) and clamping screw (missing) are at the bottom of the index arm. Three half-glass shades (two red, one green); no horizon shades. Index- and horizon glass without adjustment. Magnifier on a hinged 100 mm swivelling arm, serving the entire scale. Threaded telescope bracket, perpendicular adjustment by rising-piece and milled knob. Sight tube (63 mm); second sight tube (63 mm, incomplete). A prismatic eyepiece; an adjusting pin (perhaps from another instrument). Telescope and other parts are missing. In a square fitted mahogany box.