Designed to protect America's riches from every threat, these beautiful devices represent the evolution of lock technology during the nineteenth century, its most creative period. Many of the hand-crafted masterpieces are decorated with beautiful engraving and casting, despite the fact that their mechanical interiors would rarely be seen. They reflect the great pride in creative workmanship and the mechanical genius that characterized America at the time. Here for the first time is a comprehensive compendium of these marvels of complexity and their the fascinating history. Stunning photographs by Anne Day and learned text by the authors illuminates a remarkable but little-known chapter in American technological achievement. Over 400 color photographs.