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REDTA double-image reduction tachymeter
REDTA double-image reduction tachymeter

REDTA double-image reduction tachymeter

Date1930-1940
Inventory Number2003-1-0130
ClassificationTheodolite
Subject
    Maker Carl Zeiss Jena 1904 - 1948
    Cultural Region
      Place of Origin
        Dimensionsupright: 40.3 × 15.8 × 17.5 cm (15 7/8 × 6 1/4 × 6 7/8 in.)
        Material
          DescriptionThe REDTA instrument by Carl Zeiss Jena has the optical path of a theodolite with self reduction capabilities and a double-image distance meter.

          It has a fully reversible verticle range (i.e., it can transit) but a narrow range in azimuth and internal focusing. Three screws on the mounting plate and bubble levels are used to level the instrument.

          The instrument has an optical scale. Angles may be read through the microscope next the main telescope eyepiece.

          The bullet-shaped case is missing.
          Signedon top of optical tube assembly: CARL ZEISS / JENA [in lens logo]
          Inscribedon optical tube assembly: Redta serial number on tube assembly: Nr. 60749
          FunctionA tachymeter (or tacheometer) is a surveying instrument used for the rapid determination of distances, elevations, and bearings.

          Self-reducing double-image tacheometers are based on the system patented by Bosshardt in 1922. The first production model of the Zeiss–Bosshardt (Redta) self-reducing double-image tacheometer came out in 1927.
          transit theodolite
          Buff & Buff Manufacturing Company
          Date: circa 1905
          Accessories: wood case; leather case; right-angle prism; plumb bob; oil flask; tripod (5174b)
          Object number: 5174a
          student transit theodolite
          C. F. Casella & Co. Ltd.
          Date: 1910-1930
          Object number: 2006-1-0072
          Zeiss stand Ic photomicrographic compound microscope
          Carl Zeiss, Optische Werkstätte, Jena
          Date: circa 1902
          Accessories: oculars (5); objectives (5); microplanar objectives (2); iris diaphragm; abbe condenser; collars and sleeves for photography; parts box; Leitz object micrometer (1308b); cardioid condenser (1308d); immersion oil bottle (1308c) ; Leitz erecting prism (1308e); standing case with key
          Object number: 1308a
          Zeiss stand Ia laboratory compound microscope
          Carl Zeiss, Optische Werkstätte, Jena
          Date: circa 1898
          Accessories: oculars (4): 2, 4, and compensating oculars 6, 8; objectives: AA, DD, a2, and apochromat HI 2.0 mm; triple nosepiece; swing-out condenser with iris-cylinder diaphragm; disk diaphragm and central stop diaphragm; filter; eyepiece micrometer, brush, spare stage clips; large mechanical stage (2006-1-0114b); centering glass (2006-1-0114c) with instructions; magnification tables (2); standing case; key; leather traveling case (2006-1-0114d).
          Object number: 2006-1-0114a
          simple theodolite and circumferentor
          Benjamin Cole
          Date: 1720-1740
          Accessories: sight vane (2), key (box)
          Object number: 5253
          altazimuth theodolite with telescopic sights
          Larose fils
          Date: 1780-1790
          Object number: DW0934
          Zeiss stand Ia laboratory compound microscope
          Carl Zeiss, Optische Werkstätte, Jena
          Date: circa 1885
          Accessories: objectives (4): A, C, F, and DD; 1 ocular: 5; small-parts box with ocular micrometer case; key; Abbe drawing camera in separate box (1125c); box to hold objectives; standing case.
          Object number: 1125
          Mohn cloud theodolite
          Norwegian
          Date: circa 1885
          Object number: 1996-1-0111
          altazimuth theodolite
          Andrew Yeates
          Date: circa 1840
          Accessories: case, second eyepiece, plumb bob
          Object number: 5235
          transit theodolite with solar attachment
          W. & L. E. Gurley
          Date: ca. 1884
          Accessories: solar attachment; case; level; green filter; sun shade; tripod (5163b)
          Object number: 5163a
          altazimuth theodolite
          Jones & Son
          Date: 1784-1790
          Object number: 5223
          Scribola adding and printing machine
          Ruthardt & Company
          Date: 1917-1927
          Object number: 1997-1-0241