Petrography Petrography Petrography is a branch of petrology that focuses on detailed descriptions of rocks. Someone who studies petrography is called a petrographer. The mineral content and the textural relationships within the rock are described in detail. The classification of rocks is based on the information acquired during the petrographic analysis. Petrographic descriptions start with the field notes at the outcrop and include macroscopic description of hand specimens. However, the most important tool for the petrographer is the petrographic microscope. The detailed analysis of minerals by optical mineralogy in thin section and the micro-texture and structure are critical to understanding the
What Is History? art. Though Carr conceded that historians cannot predict exact events in the future, he argued that historical generalizations can supply information useful to understanding both the present and the future. Carr argued that since scientists are not purely neutral observers, but have a reciprocal relationship with the objects under their study just like historians, that this supported identifying history with the sciences rather than the arts. Likewise, Carr contended that history like science has no moral judgements, which in his opinion supports the identification of history as a science. Carr was well known for his assertions in "What Is History?"