The smell of the past

Of all the ways we try to reach the past, one is almost completely shut to us. We can read what they wrote, measure what they built, restore the colour they painted. We cannot smell what they smelled. Smell leaves no ruin and no recording. It is the one sense the historical record cannot store, which is a particular loss, because for the people who lived there it was often the loudest sense in the room.

The sense that history forgot

Sight and sound get archives. Paintings, manuscripts, scores, eventually photographs and recordings. Smell gets adjectives, and not many of those, because most languages are oddly poor at naming odours directly. We say a thing smells like another thing. We rarely say what it simply smells of.

So the historian of smell works at a disadvantage that the historian of anything else does not face. The French scholar Alain Corbin, whose book The Foul and the Fragrant more or less founded the field, had to reconstruct the olfactory world of past France from complaints, regulations, medical theories, and the language of disgust, because the smells themselves were gone the instant they happened. The most immediate sense leaves the faintest trace.

A working city was a wall of odour

We should be specific, because vagueness flatters the past. A European city before sanitation was not faintly musty. It was an assault. Human and animal waste ran in the streets or sat in cesspits under the houses. Tanneries, which turned hide into leather using urine, dung, and lime, smelled so violently that they were pushed to the edge of town and downwind by law. Slaughtering, fish markets, tallow rendering, the dye trade, all of it added its own signature, and none of it was carried away by anything but rain and time.

The horse alone reshaped the air of every city on earth until about a century ago. A large nineteenth-century city moved on tens of thousands of horses, and each horse produced many kilograms of manure a day, piled at corners, ground into the streets, drying into a dust that everyone breathed. When people complained about the coming of the motor car, one real attraction was that it did not defecate.

The single most famous smell in modern history may be the Great Stink of London in the summer of 1858, when the Thames, by then an open sewer, grew so foul in the heat that Parliament, sitting beside it, soaked its curtains in chloride of lime and seriously discussed relocating upriver. The stink, more than any report, is what finally funded the city's sewers. Sometimes the nose legislates where the eye and the conscience would not.

When smell was thought to be the disease

This was not a world that merely tolerated bad air. It feared it, literally, because for most of recorded history people believed that foul smell was not a symptom of disease but the cause of it. The miasma theory held that illness rose from corrupted air, from swamps and rot and crowded bodies. Smell was a warning system pointing, as people thought, straight at mortal danger.

So the response to smell was elaborate and constant. People carried pomanders and sniffed at clove-studded oranges. Plague doctors stuffed the long beaks of their masks with herbs and dried flowers, breathing through a filter of scent against an enemy they thought was airborne and reeking. Incense, strewing herbs, perfumed gloves, rosewater: an entire material culture grew up around the conviction that to manage smell was to manage survival. The theory was wrong about the mechanism and accidentally useful about the remedy, since the places that smelled of decay often were, in fact, dangerous.

Why the missing sense matters most

There is a reason the lost sense is the one that would hit hardest if we could get it back. Smell takes a uniquely short path to the parts of the brain that handle emotion and memory, which is why a single forgotten odour can drop you into childhood faster than any photograph. It is the sense least mediated by thought. When Proust wanted to collapse the distance of years in a single sentence, he reached not for a sight or a sound but for the smell of a cake in tea.

This is the part of the past most thoroughly closed to us, and it is exactly the part that would feel least like history and most like being there. A reconstructed street can show you the mud and the painted signs and the crowd. It cannot hand you the tannery on the wind, the bread two doors down, the particular animal warmth of a city that ran on horses. You can stand in the geometry of a vanished place and still be standing in the wrong century, because the air has changed, and the air was half of what it meant to be there.