You know the sensation of pressing your nose into an antique book or walking through a historic library. But we’ve long struggled with the exact adjectives to describe these scents. Thankfully, two University of London researchers have developed guidelines for describing these characteristics through chemical analysis of volatile organic compounds. To translate this academic approach to the sensory world, the team partnered with visitors of the Birmingham Museum and Art Gallery. They formed a panel of “library smellers” and tackled St Paul’s Cathedral’s iconic Wren Library, selecting scents like “woody” and “earthy” from a list to describe their experience. These notes now populate the first ever Historic Book Odor Wheel. Learn more over at Smithsonian magazine.