There were fifteen hundred in the Survey, and the quality of their work, their capacity for visualizing plunging synclines and recumbent folds, tended to vary. She looked upon some of them as “losers.” Such people were sent to what she privately described as “penal quadrangles”: the lesser bayous of Louisiana, the Okefenokee Swamp. If they did not know strike from dip, they could go where they would encounter neither. She did not feel pity. Better to be a loser in the United States, she thought, than to be a geological peasant in China. There are four hundred thousand people in the Chinese Geological Survey. “It’s a hell of an outfit,” in Anita’s words. “If they want to see exposed rock, they don’t depend on streambanks and roadcuts, as we do. If an important Chinese geologist wants to see a section of rock, the peasants dig out a mountainside.” She was a map editor for seven years, during all of which she flexplek huren amsterdam continued her conodont research, almost wholly on her own time. Collecting rock from Maryland and Pennsylvania, she crushed it and “ran the samples” at home. Running samples was not just a matter of pushing slides past the nose of a microscope. After pulverizing the rock and dissolving most of it in acid, she had to sort its remaining components, and this could not be done chemically, so it had to be done physically. It was a problem analogous to the separation of uranium isotopes, which in the early nineteen-forties had brought any number of physicists to a halt. It was also something like sluicing gold, but you could not see the gold. Anita primarily uses tetrabromoethane, an extremely heavy and extremely toxic fluid that costs three hundred dollars a gallon. Granite will float in tetrabromoethane. Quartz will float in tetrabromoethane. Conodonts sink without a bubble. Her hands in rubber gloves within a chemical hood, she pours the undissolved rock residue into the tetrabromoethane. The lighter materials, floating, are removed. Inconveniently, conodonts are not all that sink. Pyrite, among other things, sinks, too. With methylene iodide, a fluid even heavier than tetrabromoethane, she turns flexplek huren eindhoven the process around. In methylene iodide, the pyrite and whatnot go to the bottom, while the conodonts, among other things, float. Electromagnetically, she further concentrates the conodonts.