Petrography rock was affixed to a microscope slide and then ground so thin that light could be transmitted through mineral grains that otherwise appeared opaque. The position of adjoining grains was not disturbed, thus permitting analysis of rock texture. Thin section petrography became the standard method of rock study. Since textural details contribute greatly to knowledge of the sequence of crystallization of the various mineral constituents in a rock, petrography progressed into petrogenesis and ultimately into petrology. It was in Europe, principally in Germany, that petrography advanced in the last half of the nineteenth century. The macroscopic characters of rocks, those
What Is History? sometimes been made to treat history as a branch of sociology." About the rise of social history as a subject at the expense of political history, Carr wrote:"Social history is the bedrock. To study the bedrock alone is not enough; and becomes tedious; perhaps this is what happened to Annales. But you can't dispense with it". Through Carr himself had insisted that history was a social science, he regretted the decline of history as a discipline relative to the other social sciences, which he saw as a part of a conservative trend. Carr wrote: "History is preoccupied with fundamental processes