Optical diagrams showing light shone through prisms and the resulting spectral patterns. Four figures lettered ga-gb and Ea-Eb. Plate 6 from the monograph "Merkwurdige phanomene an und durch verschiedene prismen: zur richtigen wurdigung der Newton'schen und der von Gothe'schen farbenlehre", [Remarkable phenomena at and through different prisms to correct Newton's and Goethe's theories of colours] by Johann Friedrich Christian Werneburg (Nuremberg, 1817). Engraved top right "Tabula 6" J F C Werneburg (1777-1851) was a Professor at the University of Jena.