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 conclusion which does not need strengthening by what could have been found in the destroyed research material". (Another problem is the boy:girl ratios in the study; the ratio in the control group is 1:1, whereas the ratio in the index groups is 4:1.) The major Swedish newspapers have had tens of stories on the controversy: Dagens Nyheter, Svenska Dagbladet, Göteborgs-Posten, etc. There was also a one-hour program about DAMP on Swedish TV that discussed the controversy over Gillberg's Gothenburg study at length. In Norway, the newspaper Dagsavisen ran a series of critical stories. The Gothenburg Study of Children with DAMP