An incorrigible tinkerer with boundless curiosity, the author of The Elements brings the perfect combination of know-how, humor, and daring-do to every project or demonstration, be it scientific or mechanical. Looking back on an era when objects were physical rather than virtual, Theodore Gray explores the mechanical underpinnings of dozens of types of machines and mechanisms, offering succinct explanations and color photos of locks, radios, the cotton gin, the wristwatch, a sewing machine, the industrial loom, and those landline phones that were attached to the wall by an annoying cord.