Before the churn of factories and the tang of coal smoke came to dominate modern life during and after the Industrial Revolution, the smells of daily life were intensely organic, shaped by proximity to animals, bodies, plants, and decay. Urban and rural environments offered distinct olfactory experiences, but both were pungent, earthy, and changed with the seasons.

Once industrialization and modern sanitation systems had taken hold in the industrialized world by the mid-1800s (following a transformation that lasted about a century), the smells of waste, sewage, manure, and other organic materials were significantly less common, even in rural areas. Changes in agriculture, the decline of small cottage industries, and advances in chemistry also pushed scents away from earthy and toward synthetic. But understanding these historical odors offers a visceral glimpse into how people once experienced the world — as they say, “the nose knows.”