MAURITS SNELLEN was born on April 1, 1840, in the village of Zeist, not far from Utrecht. After visiting the gymnasium at Gouda, he entered the University of Leiden and devoted himself to the study of mathematics and physics. As a result of this study, he obtained the degree of doctor of mathematics and physics in 1865. From 1863 to 1864 he was a teacher of physics and mechanics at Leiden, then from 1864 to '67, teacher of physics in the gymnasium at Groningen, and lastly from '67 to '73 teacher of mathematics at Delft.