"Reveals in pictures, prose, and perspective the experience and knowledge gained by the author from years of acquiring, studying, and restoring sextants from earlier times and from around the world. This fascinating book owes much of its attraction to the expert description and photos of the mechanics of the sextants and their subassemblies. It is also the story of how different manufacturers, in different times and places, solved the same mechanical problems in different ways in order to perfect one of the most accurate mechanical devices ever produced by man. All of this is complemented by an historical overview which has never been published until now"--Book jacket flap.