The smell of snow is a paradox - it is extremely ethereal and often described as a distinctly neutral watery freshness or even as an acute absence of odor. We meet it as a symbolic means of conveying the feeling of being somewhere in between, of non-presence, of restraint and of stagnation. It's elusive, but always present during the short winter days, thus being a perfect metaphor for frustration, isolation, illness, eternity, death, but also rebirth. Snow covers everything, soothes feelings, softens the bitter bitterness of days gone by. In Edith Wharthon's novel Ethan Frome, snowy winter is a psychologically and physically stifling force, with its white hues masking collective handicaps and weaknesses; in James Joyce's Dubliners, snow falls indiscriminately on the living and on the dead; in Erich Maria Note's Heaven Has No Favorites, the snow is the equivalent of the medieval moats around the lazar houses that muffle the distant rumble of the outside world; in Laura Munson's story The Smell Of Snow, it's the way to describe something unsettling that comes your way. There is somewhere between the scent of the winter breeze and the rainy day. The main thing about snow in literature and in perfumery is that it is most often seen in relation to other things that somehow are in contact, appear nearby, or demonstrate recognizable visual similarity. The most unusual fragrant allusions, however, appear in Russian literature from the end of the 19th - beginning of the 20th century: seasonal fruits, preserved or candied, often exotic for the inhabitants of the snowy lands, such as watermelon, apples and cranberries, or even vegetables and watery vegetables, like cucumber. The smell and appearance of snow is very associative in Europe and North America: it resembles the smoky scent of stoves and fireplaces, where charcoal and birch or pine wood burn, and years of childhood with the innocent and milky smells of his body, of wool and winter games and sports. It most certainly smells of Christmas Eve and festive delicacies, and the taste of powdered sugar. And it's also widely used as a metaphorical descriptor for something taboo: associations with the smell of snow can get bloody and metallic, but it takes a long story with a few accompanying images to unfold. The smell of snow is a priori more complex than any smell of a flower or fruit, because it is a multi-layered sensation, not only olfactory, but also trigeminal, which has much more to do with tactile perception and a cold-sense modality. The smell of snow resembles watermelon and iron due to traces of unsaturated aldehydes and their epoxy derivatives. These substances appear in the snow thanks to the vital activity of unicellular algae with the romantic nickname of snow algae or snow watermelon, or blood snow - lat. Chlamydomonadas nivalis: microorganisms that feel comfortable in icy blanket. Their metabolic activity transforms linoleic acid into several aldehydes, including normal and nonadienal - their smell resembles that of fresh cucumber, watermelon and violet leaf. Besides chlorophyll, snow algae produce a pigment, astaxanthin, which makes them cheeky pink - they are also responsible for the characteristic rich pink color of the feathers and salmon flesh of the American flamingo. The bigger they feel, the more they reproduce, thus giving a pink appearance to entire snowy valleys hence their name, pink or snow watermelon, but 4 � C is already too hot for them. Cold activates the trifacial nerve and the smell of algae metabolites, and this is what makes the smell of snow so different from the smell of fresh water - or the smell of rain as as such, for example. The snowy shade in perfumery is usually recreated using aldehyde, aquatic and ozonic scent substances, but the textual replication of the scent of fresh snow is rarely good enough and usually does not stand up to scrutiny.