Smells affect us strongly since they are linked to primal activities, like eating and mating, which are in turn connected to our survival as individuals and as a species. Probably as a result, smelling can be more powerful than seeing. Consider the difference between seeing a sewer pipe and inhaling its fumes.
Like sounds, odors alert us to things we cannot see, such as the smell of leaking gas. Perhaps precisely because we use it less often, when our sense of smell is aroused by a pungent odor, we react strongly and recall it acutely.
Once, years ago, camping with my friend Richard along the Atlantic coast I contracted a bad cold. We had stopped for the night at a lonely tidewater stretch where a farmer was showing us places to pitch our tent. I favored a lovely spot, protected by a chest high mortared wall but with a view out to the breaking waves and setting sun. Richard demurred, insisting on a more exposed rocky site along the shore. When the farmer left, Richard explained, “Behind that wall was the manure pit. It stank to high heavens. You just couldn’t smell it because of your cold!” He undoubtedly remembers the smell—and the place—vividly; I remember the fun and folly of not smelling it.
Just as we look for other people, we sense them odiferously as well. As someone approaches us, we shift from seeing to seeing and smelling, especially after the person starts talking. We can begin to smell their breath, sweat, or cologne. Smell, and to a greater degree touch, serve as a basis for allowing—or preventing—others entering the range of intimacy, that is, within 2-3 meters/6-10 ft of us.
Smells are also linked to the earth, defining its places and seasons—spring’s flowers, summer’s mown hay and grass, fall’s damp earth and burning leaves (do people somewhere still burn leaves?), winter’s wood smoke. Thus, smell can be an effective design attribute. “We know a Greek garden redolent of ouzo and onions, and a Turkish garden that reeks of raki and roses,” wrote the architect Charles Moore. “Recollections of Indian gardens are evoked, for us, by the scents of incense, coconut oil, teapots, or smoke from picnic fires.”
Odors are not simply site identifiers. They can actively stimulate other functions of our bodies. Pleasant odors like lily of the valley, citrus, and peppermint have been linked not only to pleasant feelings of happiness and optimism but also to physical activation and alertness. Other research indicates the smell of rosemary may improve memory.
Despite the power of odors, most humans rely on them very little to interpret the world. The human smell sensors, the olfactory bulbs, have shriveled to a third the normal proportional primate size, which is already tiny by mammalian standards. We can see the result on any walk with a hunting dog. It is zigzagging forward and back, side to side, immersed in a world abuzz with the smells of creatures that have passed this way.
More than that, contemporary humans seem bent on avoiding smells. We work assiduously to remove odors from antiseptic office buildings and hybridize flowers to be large, colorful, and scentless. Even the words “smell” and “odor” now almost invariably refer to unpleasant scents.
Beyond avoiding the undesirable, design can still focus on smell, for the deaf, blind, or fully sensed. For a blind client, architect Moore incorporated a variety of smells into a house he helped design. The odors identified regions of the house as the homeowner moved around.
Meanwhile, fragrant early-blooming shrubs like viburnums planted close to house entries still help draw us outdoors. In several seasons, chamomile, woolly thyme, and other low-growing herbs perfume lightly used treadways, especially when crushed underfoot. Fragrances are especially suited to strolling paths where they can be fully appreciated.
Despite our predilections, smells light and heavy, fragrant and putrid link us back instantly years later, like the tasting of a madeleine, to a particular time and place.