Photogravure after a painting by Beltz, c 1860. Christian Friedrich Schonbein (1799-1868) was a German chemist. He taught at the University of Basel, Germany, first as the chair of chemistry and physics, and later as a profesor. He is best known for his discovery of ozone in 1840, and for developing guncotton and collodion through his work on nitrocellulose in 1846. From a collection of portraits of scientists published by Photographische Gesellschaft, Berlin, c 1910. Dimensions: 460mm x 340mm.
© Science Museum / Science & Society Picture Library