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    Optic cased for comments

    Hi,

    please tell more about this optic,
    it was just found in the house of an old "résistant" .

    and please give me an idea of value because i plan to sell it
    Attached Files

    #2
    optic
    Attached Files

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      #3
      Looks like an unusual Teodolite.
      Seems the functions are all there, but the design is weird.

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        #4
        Thank you Mike !
        More opinions are welcome ...

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          #5
          Hello LOTHRINGEN,

          I'm sure that there's an official name for it, but it's basically a simple Theodolite / Level for surveying & construction. The upper telescope-mounted section resembles an 'Abney Level' whereby a target is sighted thorough the telescope and the Vertical angle is adjusted using the thumb-screw until the spirit-level is levelled (when viewed through a reflection in a mirror inside the lower portion of the telescope).

          Your example is staff-mounted, and includes an Azimuth (Horizontal) so that angles between targets can also be taken, so overall a very useful instrument for simple construction or mapping where speed and portability is paramount over accuracy.

          I don't have any period photos of them in use, so I can't confirm for what purposes they were actually used (or by whom), but as a general surveying instrument I would expect it to be used for mapping and quick / simple construction where speed is more important than accuracy, and consequently used instead of a full-blown Theodolite with tripod and targets etc.

          Within the telescope, and in addition to the simple cross-hair, are there additional horizontal 'Stadia' lines both above and below the central horizontal line? - although I wouldn't expect this to be the case unless the telescope had a significant >10x optical magnification, please confirm? Also please confirm whether the telescope has any magnification at all?

          I'm unfamiliar with the vertical scale range of 0 to 20 measurement range to represent a 90-degree elevation, so I am unsure of units. Also, I can't read the other scale that is engraved onto the instrument (although I'd guess that it's a Tangent scale?), so I would be grateful if you can add additional close-up photos of the vertical scale engravings from 0 to 20 on the inside, and also that of the outer scale that will perhaps explain their units and usage?

          Kind regards,
          Paul

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            #6
            Have you seen this one ?

            http://www.ebay.de/itm/Messinstrumen...54258105949670

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