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
Samuel Ludwik Zasadius Samuel Ludwik Zasadius Samuel Ludwik Zasadius or "Zasadyus", "Sassadius" (c. 1695–1756) was a Polish religious writer, pastor and author of popular sermons and prayer-books. He was also known for propagating Polishness in Cieszyn Silesia. Zasadius was born c. 1695 in Komorzno as the son of a Polish pastor. He studied in Wittenberg and Jena. In the years of 1721–1730 Zasadius was a deacon and preacher of Jesus Church in Cieszyn. He led educational activity, published Polish magazines and learned the Polish language. In 1730 he was expelled (with pastors Johann Adam Steinmetz and Jan Muthmann) from the Austrian monarchy for