Petrographic methods, the authorized English translation of Part I, Anleitung zum Gebrauch des Polarisationsmikroskops (3d. rev. ed.) and Part II, Die gesteinbildenden Mineralien (2d. rev. ed.)
A laboratory manual on the polarizing microscope and rock-forming minerals, translated by Robert Watson Clark from Ernst Weinschenk's German texts and issued by McGraw-Hill in New York in 1912 for geology students and petrographers. The plates are line diagrams: crystal sections with Miller indices and angle measurements, optical axis figures, and ruled prisms showing light paths, useful as fine-line geometric ornament and technical labelling.
