Book excerpt: Million-copy bestselling author of The Elements, Molecules, and Reactions Theodore Gray applies his trademark mix of engaging stories, real-time experiments, and stunning photography to the inner workings of machines, big and small, revealing the extraordinary science, beauty, and rich history of everyday things. Theodore Gray has become a household name among fans, both young and old, of popular science and mechanics. He's an incorrigible tinkerer with a constant curiosity for how things work. Gray's readers love how he always brings the perfect combination of know-how, humor, and daring-do to every project or demonstration, be it scientific or mechanical.In How Things Work he explores the mechanical underpinnings of dozens of types of machines and mechanisms, from the cotton gin to the wristwatch to an industrial loom. Filled with stunning original photographs in Gray's inimitable style, How Things Work is a must-have exploration of stuff--large and small--for any builder, maker or lover of mechanical things.