NUTS AND BOLTS

The author of Built returns with an exploration of the “fundamental building blocks without which…complex machinery wouldn’t exist.”

As structural engineer Agrawal ably demonstrates, from the dishwasher to the International Space Station, modern life depends on some combination of the nail, wheel, spring, magnet, lens, string, and pump. With the invention of the nail, our ancient ancestors could build houses, boats, weapons, and other vital things. Made by hand until the 19th century, metal nails were so expensive that people who moved often burned down their house to recover them. A family of nail cousins—rivets, screws, and bolts—followed. So ingenious is the wheel that some historians argue that it wasn’t independently invented many times, as some believe, but by a single genius whose invention quickly spread across Eurasia. Wheeled transportation conquered much of the world nearly overnight about 6,000 years ago. Springs store and release energy when they change shape. Perhaps the first was the bow, but today they take part in the widest range of inventions. As dampers against noise, vibration, and earthquakes, springs support machinery and even entire buildings. The magnet, a natural phenomenon, is the basis of essentials in the modern world from light bulbs to the internet. Curved glass (i.e., lenses) was known since the dawn of civilization, but humanity didn’t hit the jackpot until the 17th century produced the microscope and telescope. Readers searching for simple explanations of how things work may prefer Henry Petroski; Agrawal, an expert guide, emphasizes the big picture. She often compellingly digresses into related areas such as the varieties of string instruments and her personal experience with in vitro fertilization. Discussing the final invention on her list—the pump—the author emphasizes the heart, but also covers breast pumps and related topics.

A quirky, entertaining riff on the building blocks of engineering.