Steinhaus longimeter

The Steinhaus longimeter, patented by the professor Hugo Steinhaus, is an instrument used to measure the lengths of curves on maps. It is a transparent sheet of three grids, turned against each other by 30 degrees, each consisting of perpendicular lines spaced at equal distances 3.82 mm. The measurement is done by counting crossings of the curve with grid lines. The number of crossings is the approximate length of the curve in millimetres.

Bibliography

* Hugo Steinhaus: "Mitteilungen der Sächsischen Akad." 82, 120–130, 1930.
* Hugo Steinhaus: "Przeglad Geogr." 21, 1947.
* Hugo Steinhaus: "Comptes Rendus Soc. des Sciences et des Lettres de Wrocław", Sér. B, 1949.
* Hugo Steinhaus: " [http://books.google.com/books?id=N63XpD1oJ6IC&printsec=frontcover&source=gbs_summary_r&cad=0 Mathematical Snapshots] ", 3rd ed. New York: Dover, pp. 105–110, 1999.

External links

* [http://mathworld.wolfram.com/Longimeter.html Weisstein, Eric W. "Longimeter."] From MathWorld — A Wolfram Web Resource.
* [http://www.rechnerlexikon.de/en/artikel/Longimeter Informations about patent] (DRGM 1241513)