The river rises northwest of Halle (Westf.) on the Große Egge, crosses the Hermannsweg, flows through the villages of Hesseln and Hörste in Halle borough, then through the borough of Versmold through Oesterweg, continuing through the town of Sassenberg and along the southern edge of Milte in the borough of Warendorf, before emptying into the Ems near Warendorf-Einen.
Jules et Jim was based on the triangle between Roché, Franz Hessel, who translated Marcel Proust into German, as did the character Jules, and Helen Grund, who became Hessel's wife.
Prior to this posthumous re-publication of Hessel's investigations, similar findings had been reported by the French scientist Auguste Bravais (1811–1863) in Extrait J. Math., Pures et Applique ́es (in 1849) and by the Russian crystallographer Alex V. Gadolin (1828 - 1892) in 1867.
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Hessel also found Euler's formula disobeyed with interconnected polyhedra, for example, where an edge or vertex is shared by more than two faces (e.g. as in edge-sharing and vertex-sharing tetrahedra).
Hessel's best known invention is probably the Femidom, also called the female condom, launched worldwide in 1991, and today sponsored by World Health Organization and the United Nations.