Weirdly, Canals and Trains Made Pre-Civil-War Americans Smaller

A strange thing happens on the way to modernity: people get sicker and shorter.

That’s the “Antebellum Puzzle,” a term for the measurable decline in health of the U.S. population in the four decades ahead of the Civil War, even as urbanization and industrialization sent GDP skyrocketing. Historians have shown that during the economic-boom decades between 1820 and 1860, heights and lifespans shrank for the average American—including white men and women, as well as free black men and women—by as much as an inch.