Carl Elsener Sr. Carl Elsener Sr. Carl Elsener Sr. (also known as Charles Elsener, born 6 July 1922 in Ibach, † 1 June 2013 in Schwyz) was a Swiss entrepreneur. Carl Elsener was the grandson of Karl Elsener (1860-1918) and the son of Carl Elsener (1886-1950). Karl Elsener had opened a factory in Ibach for the production of knives and surgical instruments, from which the knife factory Victorinox developed. Carl Elsener led the company initially with his father and his brother Eduard Elsener (b. 1926). After the death of his father in 1950, he took over the management. The Swiss Army Knife is
Karl Weissenberg studied at the Universities of Vienna, Berlin and Jena with Mathematics as his main subject. He published on the theories of Symmetry groups and Tensor and Matrix algebra, then applied mathematics and experimentation to crystallography, rheology and medical science. Karl Weissenberg Karl Weissenberg (11 June 1893, Vienna – 6 April 1976, The Hague) was an Austrian physicist, notable for his contributions to rheology and crystallography. The Weissenberg effect was named after him, as was the Weissenberg number. He invented a Goniometer to study X-ray diffraction of crystals for which he received the Duddell Medal of the Institute of Physics in