The Invention of the Assembly Line

Gr 3–5—Some engineering feats are so deeply woven into the fabric of the United States that it is hard to imagine a time when they were only an idea, a vision. This series explores the histories of various engineering marvels from their inception to the present day. Each title begins with a page of "Fast Facts," where a half-dozen key points such as location, size, purpose, and cost are listed. A page with a time line comes next, followed by the main content. The writing is substantive and engaging. Interspersed among solid answers to the wheres and hows are stories about some of the people involved. For instance, in Golden Gate Bridge, readers learn that a safety net for construction workers cost $100,000 to install. The author adds a human element by describing how one worker, Al Zampa, was saved by the net after he fell from a steel beam. The illustrations are amazing, especially photographs of the construction process. One image, for example, depicts workers standing outside a diversion tunnel in the Hoover Dam, who are tiny compared to the tunnel—a vivid reminder of the enormity of the project.