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
The Gothenburg Study of Children with DAMP The Gothenburg Study of Children with DAMP The Gothenburg Study of Children with DAMP was a study of six-year-old children in Gothenburg, Sweden that began in 1977. The purpose was to find out what proportion of the children had Deficits in Attention, Motor control and Perception (DAMP), formerly known as Minimal Brain Disorder (MBD), and to follow the development of that group over the years. The results and discussions have been published in four dissertations and approximately 30 scientific papers. The first phase of the study was designed mainly by Christopher Gillberg and Peder Rasmussen. Initially, preschool teachers in all