A variscale is variable length mechanical scale (ruler) designed to directly measure

latitude In geography, latitude is a geographic coordinate system, geographic coordinate that specifies the north-south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from −90° at t ...

and

longitude Longitude (, ) is a geographic coordinate that specifies the east- west position of a point on the surface of the Earth, or another celestial body. It is an angular measurement, usually expressed in degrees and denoted by the Greek lett ...

USGS The United States Geological Survey (USGS), founded as the Geological Survey, is an government agency, agency of the United States Department of the Interior, U.S. Department of the Interior whose work spans the disciplines of biology, geograp ...

maps.Roos, M., 1967. Variscale stereo point marking instrument, Photogrammetric Engineering, 33(11):1260-64.

References

External links

Instructions for using the Variscale
Measuring instruments Cartography {{Cartography-stub