Louis Émile Javal of text, but make short rapid movements (saccades) intermingled with short stops (fixations). Javal's observations were characterised by a reliance on naked-eye observation of eye movement in the absence of technology. Javal's interest in strabismus was due to the disorder affecting his father and sister. Javal himself had heterochromia. At middle-age Javal developed glaucoma, and by 1900 was totally blind. He was a friend of Ludwik Łazarz Zamenhof (1859-1917), the inventor of Esperanto, and he stressed the importance of learning this language by the blind. In addition, he was involved in social reform issues that included education and circumstances surrounding
Ludwik Kalkstein October 1994, in Munich, Germany. Ludwik Kalkstein Ludwik "Hanka" Kalkstein, also known as Ludwik Kalkstein-Stoliński, (13 March 1920, Warsaw – 26 October 1994, Munich); was one of the better known German Gestapo agents during the Warsaw Uprising as well as a Stalinist informant following the Soviet takeover of Poland. Along with his wife (Blanka Kaczorowska "Sroka"), they became traitors to the Armia Krajowa under not just one but two consecutive totalitarian regimes. Kalkstein was responsible for the arrest and execution by the Nazis of at least fourteen Polish underground officers, including the General Stefan Rowecki. Arrested by the Gestapo in