preservation

Cecilia Bembibre and Matija Strlič remember how it smells to enter the library of Dean and Chapter.

The library is nestled above the main floor of St. Paul’s Cathedral in London, tucked away behind the southwest tower. Coming through the long stone corridors of the cathedral, a visitor is met with a tall wooden door, usually kept closed. The outside world might be full of the smell of fumes from central London’s busy roads or the incense that wafts through the church, but once you open that door, a different smell envelops you. It’s woody, musty, and a little bit familiar.

“It is a combination of paper, leather, wood ... and time,” said the pair.

Bembibre and Strlič are scientists from the University College London’s Institute for Sustainable Heritage. Many people might find the aroma of an old, yellowing book nostalgic, but for Bembibre and Strlič, it can be so much more.

For them, what we smell is just as much a part of our heritage as what we see or hear — and they’re on a mission to preserve it.

Though the first thing to come to mind when imagining a "historic odor" might be something like London’s Great Stink, odors don’t just need to be exceedingly unpleasant to be historically relevant. Anyone born after 1960 might get a whiff of childhood nostalgia when smelling Play-Doh’s sweet, yet pungent aroma, for example. Bembibre and Strlič want to create a scientific way to describe those kinds of smells.

For their latest work, the pair used both high-tech chemistry and an old-fashioned human nose to document the smell of books.

Volunteers were asked to describe either the aroma of the cathedral library (woody, smoky, vanilla) or antique books (chocolate, burnt, mothballs). Bembibre and Strlič then combined these descriptors with analyses of the faint, airborne scent-laden chemicals (known as VOCs) that the items or locations were giving off.

The pair then synthesized these findings into the Historic Book Odour Wheel, which pairs the chemical signatures and human descriptors together. Using it, you can see that a book with a rich caramel smell might be impregnated with the chemical furfural or one with an old-clothing funk might be giving off the chemical hexanal.

This wheel is a step toward creating a more standardized scientific vocabulary around aromas, which could be useful for many areas, not just books. Museums, for instance, could use this kind of chemical analysis to build scent profiles of modern cultural attractions or reverse engineer the smell of some long-gone food, event, or time.

"By documenting the words used by the visitors to describe a heritage smell, our study opens a discussion about developing a vocabulary to identify aromas that have cultural meaning and significance,” said Bembibre in a press release.

Museums and organizations are already embracing scent as a part of our heritage.

The Jorvik Viking Centre in York, England, for example, used scents to recreate the authentic aroma of 1,000-year old Vikings. On the sweeter-smelling side of things, the town of Grasse, located in the hills of the French riviera, is pushing UNESCO to officially recognize their centuries-old perfumeries.

In 2001, Japan’s Environmental Ministry created a list of 100 natural and cultural sites with especially beautiful or poignant scents, such as the smell of sulfurous hot springs, lavender blossoms, or grilled eel.

“We hope that this will raise awareness of people at the local level and lead to a rediscovery of fragrant areas and their preservation,” said ministry official Tetsuo Ishii at the time.

“Our knowledge of the past is odourless,” the authors write in their paper. But our lives aren’t.

Perhaps it’s fitting for us to finally consider odors as part of our historical heritage, given their special relationship with memory. Unlike sight, sound, or touch, our olfactory bulbs have direct connections to the parts of the brain that control emotion and memory. This could be why research has shown that odor memories are often unusually vivid and emotional.

“Every day we encounter hundreds of smells, and they have an impact on how we think, feel and behave," said the authors in an email. Though we tend to ignore them, we can all conjure up personal, emotional memories through smells, whether it's the scent of cherry blossoms, your dad's cologne, or even opening up a special book.

The authors are now inviting other scientists, philosophers, and researchers to talk about what a heritage smell archive would look like. Perhaps it’d be made up of physical samples or detailed chemical signatures or stories of human life. Perhaps all of the above.

Their work was published in the journal Heritage Science.