Pt. 1. Introductory and general: scope of petrology; history; methods of study -- Chemical composition of the Earth's crust and its component minerals -- Pt. 2. Rock minerals: important properties of minerals -- The rock-making minerals -- Determination of rock minerals -- Pt. 3. Rocks: general petrology of igneous rocks -- Classification of igneous rocks -- Description of igneous rocks -- Origin and classification of sedimentary rocks -- Description of detrital sedimentary rocks -- Description of sedimentary rocks, mainly nondetrital -- Origin and classification of metamorphic rocks -- Description of metamorphic rocks -- Determination of rocks