This book is about one of the most attractive and tactile forms of slide rules, the pocket-watch slide rule. Although pocket-watch slide rules were not the most

Popular Mechanics inspires, instructs and influences readers to help them master the modern world. Whether it’s practical DIY home-improvement tips, gadgets a

Popular Science gives our readers the information and tools to improve their technology and their world. The core belief that Popular Science and our readers sh

Popular Mechanics inspires, instructs and influences readers to help them master the modern world. Whether it’s practical DIY home-improvement tips, gadgets a