Share your favorites on Show & Tell

German Made Map Measure (Opsiometer)

In Tools and Hardware > Rules and Rulers > Show & Tell and Military and Wartime > World War Two > Show & Tell.
Rules and Rulers70 of 139Unknown toolHamilton Watch Co. Map Measure (Opisometer)
Love it
Like it

pops52pops52 loves this.
SEAN68SEAN68 loves this.
antiqueroseantiquerose loves this.
GeodeJemGeodeJem likes this.
officialfuelofficialfuel loves this.
kerry10456kerry10456 loves this.
TreyTrey loves this.
walksoftlywalksoftly loves this.
blunderbuss2blunderbuss2 loves this.
vetraio50vetraio50 loves this.
mikelv85mikelv85 loves this.
aghcollectaghcollect loves this.
fortapachefortapache loves this.
See 11 more
Add to collection

    Please create an account, or Log in here

    If you don't have an account, create one here.

    Create a Show & TellReport as inappropriate

    Posted 7 years ago

    (283 items)

    This Map Measure (Opsiometer) is different from the Hamilton Watch Co. Opsiometer I previously posted

    On this German made opsiometer, the dial is marked "Inches to Miles" and "Centimetres to Kilometres" instead of just "Inches" & "Centimeters" as on the Hamilton model.
    It also has a compass on the reverse side and a mechanical pencil in the handle.
    It is also believed to be made in the 1940's for use by the military.

    Wikipedia definition of an opisometer:

    An opisometer, also called a curvimeter, meilograph, or map measurer, is an instrument for measuring the lengths of arbitrary curved lines.
    An opisometer
    A simple opisometer consists of a toothed wheel of known circumference on a handle. The wheel is placed in contact with the curved line to be measured and run along its length. By counting the number of teeth passing a mark on the handle while this is done, the length of the line can be ascertained:
    line length = wheel circumference × teeth counted/teeth on wheel.
    In more sophisticated models, sometimes called a chartometer, the wheel is connected via gearing to a rotary dial from which the line length can be directly read.[1]
    The instrument is most commonly used to measure the lengths of roads, rivers and other line features on maps. Opisometers designed for this purpose provide scales reading the measured distance in kilometers and miles.
    Early versions of this instrument were patented in 1873 by the English engineer Edward Russell Morris.[2] The instruments he produced were initially described as a Patent Chartometer although later versions were sold under the curious name of Wealemefna.[3] Writing in 1881, Morris described how he had created a wholly original name in an attempt to outwit his imitators; he also refused to disclose the origin of the word.[4]

    Thanks for looking,

    Rules and Rulers
    See all
    Super Rare 24
    Super Rare 24" 3-Fold Boxwood Carpe...
    Antique Rule Sector Proportional Compass Drawing Instrument J Archbutt London
    Antique Rule Sector Proportional Co...
    Antique Tubular Nickel Drawing Instruments Tool Pencil Set Pens Rule Accessories
    Antique Tubular Nickel Drawing Inst...
    Super Rare 24
    Super Rare 24" 3-Fold Boxwood Carpe...
    See all


    1. pw-collector pw-collector, 7 years ago
      Hamilton Watch Co. Opsiometer:

    2. pw-collector pw-collector, 7 years ago
      Thanks for the appreciation:
    3. pw-collector pw-collector, 7 years ago
      Thanks vetraio50 for the appreciation.
    4. pw-collector pw-collector, 7 years ago
      Thanks BB2 for the appreciation.
    5. pw-collector pw-collector, 7 years ago
      Thanks for the appreciation:
    6. pw-collector pw-collector, 7 years ago
      Thanks Trey for the appreciation.
    7. pw-collector pw-collector, 7 years ago
      Thanks Kerry for the appreciation.
    8. pw-collector pw-collector, 7 years ago
      Thanks officialfuel for the appreciation.
      Thanks again GeodeJem for the appreciation.
    9. pw-collector pw-collector, 7 years ago
      Thanks for the appreciation:
    10. Hamish Hamish, 7 years ago
      I use microscopes for my work which is maybe where I get my love of scientific instruments from. Never even heard of one of these things before. Like it a lot!
    11. pw-collector pw-collector, 7 years ago
      Thanks Hamish for the comment.
    12. pw-collector pw-collector, 5 years ago
      Thanks pops52 for the appreciation.

    Want to post a comment?

    Create an account or login in order to post a comment.