Mold, Decay, and Dead Skin Cells: You Gotta Love That Old Book Smell

There are perhaps few cases in which a thing becomes in any way classier, or otherwise more pleasant, with the addition of mold. When bread grows mold, it’s time to buy a new loaf. When a wall grows mold, there is a problem that can eventually cause harm to both you and your home, if left untreated. Mold is broadly considered undesirable, unhygienic, and a signifier of decay.

And yet moldy cheese is considered a delicacy. Blue cheeses, veined throughout with a blueish mold, are commonly served and eaten with wine after fancy dinners, and many other occasions. The mold, in this context, brings with it a sought after taste. A pleasant something.

This might appear to have nothing to do with books. Except for one thing. That smell that old books have- that sweet, dusty, delightful smell- the one that paper book enthusiasts talk about ad nauseam? That is, in part, caused by mold and decay. So again, that signifier of decay is attracting us, rather than repelling us, as decay is usually wont to do.

[As an irrelevant aside: the distinctive, and not at all book-like, smell of many such cheeses is caused by the same bacteria that cause foot odor.]

The “old book” smell is caused by a number of factors, and is largely the result of the materials the book is made of slowly breaking down (in effect, decaying) over time. Books, particularly older books, can be made entirely of organic materials: the paper, the ink, the glue, and the fabric. So from the time that book was made, it has been slowly but surely dying. Gently decaying.

The rate at which this occurs depends on many factors from the book’s environment. Heat, light, and humidity play their part, as do chemicals within the materials of the specific book. Cheap paper that is too acidic will greatly speed up the death process.

Of course, it’s not just mold and decay The materials that books tend to be made of are in the habit of absorbing smells that they come into contact with: tobacco, food odors, coffee odors (or, less fortunately, actual coffee). These smells and substances soak into the pages, adding themselves to the overall scent that may develop over many years, decades, or even centuries.

And then as a final note to add to the book smell, there is the dust. Dust being an unavoidable factor of life, there’s a more-than-fair chance that within a book’s lifetime a considerable amount of dust will have settled upon (and within) that book. Dusty books in dusty libraries can have a certain romance to them. But dust brings us back around to decay. Domestic dust is made up of many components, among them dead hair, dead skin cells, and so on. So classy.

So enjoy that delicious old book smell. Read your books with love as they slowly perish. Think something pretentious about death and decay. But do it all classily with a slice of Stilton (or your blue cheese of choice).

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