7 inch altazimuth theodolite by Troughton, early 19th century 7 inch altazimuth theodolite by Troughton 1801-1850
Refracting telescope of 2 1/4 inch aperture and 36 inch focal length by Trougton, London on an adjustable equatorial mounting with spirit level and tripod stand and box. Accessories include, 2 eyepieces, key , diagonal and filar micrometer. Refracting telescope of 2 1/4 inch aperture and 36 inch focal length by Trougton 1790-1826
18 inch repeating circle, by Troughton, engraved F5TO, 3 eyepieces 3 dark glasses, 1 plumb bob, 4 brass clips, 2 brass labels with chains, instrument is exhibited on stand with 3 levelling screws, circles are divided into twelths of a degree and read to 5" arc by vernier 18 inch repeating circle 1790-1826
Hassler's reflecting circle, 11-inch diameter with counterpoise stand, by Troughton, London in case, no key [RAS No.43, Sheepshanks No.17]. Presented to the Royal Astronomical Society in 1857 by Miss Anne Sheepshanks sister of Rev. Richard Sheepshanks. Hassler type reflecting circle with case. 1790-1826
Altazimuth theodolite, 4.5-inch, with box, by Edward Troughton, Fleet St., London, England, 1780-1826 Altazimuth theodolite, 1780-1826 1780-1826
Circular protractor by Edward Troughton, London, 9 inch with folding arms, divided on silver to 1/3 degree reading by vernier to 1-inch, engraved "Troughton, London" & "F^O 40", in case Circular protractor by Edward Troughton
Reflecting circle made by Edward Troughton, London, about 1823. Signed on the index arm: Troughton | 219 | London. Polished brass limb with inlaid silver scale from 140° to 0° to 140°; the entire circle is divided every 20'. Three silver verniers reading to 20", zeros at the left. Circular lacquered brass frame with a wooden handle. A detached U-shaped bracket holds a second handle with a brass-lined threaded hole for a third handle, which can also be screwed on the front of the frame. Three rigidly connected index arms on the back of the frame, a double-ended tangent screw and clamping screw are on the back of one of the arms. Three shades (two red, one green); three horizon shades ( two red, one green). Index glass without adjustment; adjustment of the horizon glass by a screw and a capstan screw. One detached magnifier on a 55 mm swivelling arm, for all three verniers. Threaded telescope bracket in two parts, fitted for correcting collimation error; perpendicular adjustment by rising-piece and a milled collar. Telescope (77 mm) erect image; telescope (179 mm) inverted image two parallel cross-wires; extra draw tube (90 mm) inverted image; extra draw tube (90 mm) inverted image, two parallel cross-wires. Sight tube (132 mm); sight tube (131 mm, probably from a different instrument); three shaded eyepieces (one red, two orange); a magnifying glass. Three unidentified parts. Box not seen WMB. The circle is mounted on a lacquered brass column on a tripod stand with three milled levelling screws. The counterbalanced swinging mount can be locked into the desired position by milled screws. Brass framed reflecting circle with case. 1820-1825
Circular instrument dividing engine made by Edward Troughton, London, England in 1793 and described by him in 1809. It was later modified by William Simms, his business partner after 1826, with the additional of a self-acting mechanism, the details of which Simms published in 1843. The engine has a 34-inch cast brass dividing plate with 2,160 teeth and a worm with 20 threads to the inch, all mounted on a wooden tripod base. Circular instrument dividing engine. 1793
Zenith sector telescope by Edward Troughton, London, 1800-1822. Used in America and later in Denmark Zenith sector telescope, British, 1800-1822, with components 1800-1822
Drawing in glazed frame of an early transit instrument made by Edward Troughton for his friend, Sir James South [see 1931-352]. Drawing in glazed frame of an early transit instrument made by Edward Troughton 1820