The seeds of Witold Rybczynski's elegant and illuminating new book were sown by The New York Times, whose editors asked him to write an essay identifying "the best tool of the millennium." The award-winning author of Home: A Short History of an Idea and, most recently, A Clearing in the Distance: Frederick Law Olmsted and America in the Nineteenth Century, Rybczynski once built a house using only hand tools. His intimate knowledge of the toolbox -- both its contents and its history -- serves him beautifully on his quest. One Good Turn is a story starring Archimedes, who invented the water screw and introduced the helix, and Leonardo, who sketched a machine for carving wood screws. It is a story of mechanical discovery and genius that takes readers from Ancient Greece to Victorian Glasgow, from weapons design in the Italian Renaissance to car design in the age of American industry. Rybczynski writes an ode to the screw, without which there would be no telescope, no microscope -- in short, no enlightenment science. The screwdriver, perhaps the last hand tool in a world gone cyber, represents nothing less than the triumph of precision. One of our finest cultural and architectural historians, Rybczynski renders a graceful, original, and engaging portrait of the tool that changed the course of civilization.