The system of measurement for most of the world is the metric system, and for a time in the 1970s the United States appeared ready to switch from American standard measurement. The reasons it never happened get to the root of who we think we are, just as American measurements are woven into the ways we think. John Marciano chronicles the origins of measurement systems, the kaleidoscopic array of standards throughout Europe and the thirteen American colonies, the combination of intellect and circumstance that resulted in the metric system's creation in France in the wake of the French Revolution, and America's stubborn adherence to the hybrid United States Customary System ever since. As much as Whatever Happened to the Metric System? is a tale of quarters and tenths, it is a human drama, replete with great inventors, visionary presidents, obsessive activists, and science-loving technocrats.

Anyone who reads this inquisitive, engaging story will never read Robert Frost's line "miles to go before I sleep" or eat a foot-long sub again without wondering, Whatever happened to the metric system?