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The air during the dinosaur age -

Have you ever wondered what the Earth smelled like 252 million years ago? During the Mesozoic Era, the air would have been tainted with the rancid whiff of manure, a smell not unlike a modern-day livestock pasture. This is because sauropods, dinosaurs like Aeolosaurus (pictured), munched endlessly on leaves and plants. This in turn produced huge amounts of methane, which combined with the dinosaurs' digestive juices would produce a foul odor that they'd expel either through belching or some serious rear-end venting!

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Triassic Period -

The Mesozoic Era included the Triassic Period. This is a time when the global climate was mostly hot and dry. Beasts like Plateosaurus (pictured) roamed across an arid, desert-like wilderness, which smelled of dust and dirt.

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The Jurassic Period -

The Jurassic Period, also part of the Mesozoic Era, was characterized by tropical heat and humidity. The air would have been moist and heavy with the odor of rotten leaves and sodden Earth—an environment perfectly suited to the predatory Tyrannosaurus rex.

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The Cretaceous Period -

The near-end of the Mesozoic Era included the Cretaceous Period. It's during this epoch that the first flowering plants appeared on Earth. Suddenly the air was filled with the fragrant bouquet of blooming flora, much to the delight of dinosaurs like the Secernosaurus.

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Fresh breath confidence -

According to a scientific study undertaken by archaeologists, the breath of some ancient humans very likely smelled of tree bark sap. It seems the material was often used as a remedy against halitosis, with traces of the substance found in the jawbones of our distant cousins.

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Odors of Antiquity -

Antiquity provides us with a written record of what ancient civilizations smelled like, facts also depicted in art. Pictured is a detail of a painting from the tomb of Nakht showing three ladies at a feast. They wear perfumed cones in their hair and elaborate necklaces. The figure on the right is also smelling a lotus flower.

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Ancient perfumes -

These perfumes were made with a variety of raw ingredients. The most popular 'brand' was Kyphi, likely made with terebinth resin, saffron, raisins, cinnamon, wine, myrrh, honey, and other ingredients. The exact recipe remained a secret out of respect to the gods.

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Incense odor -

We know from numerous frescos that the burning of incense was commonplace in the ancient world. These combustible bouquets were composed of herbs like cassia, cinnamon, styrax, and sandalwood.

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Scented resins -

Frankincense and myrrh are both mentioned in the Bible. These aromatic and earthy scents are derived from tree resin and are long associated with religion and spirituality.

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Roman sarcophagi -

The Romans used myrrh and turpentine (obtained by the distillation of resin harvested from living trees, mainly pines) to scent the interior of sarcophagi prior to burial during funeral ceremonies. The pungent odor was believed to deter evil spirits from entering the soul of the deceased.

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Smell of death -

Medieval cities have often been described as places reeking of death, decay, and waste. And as this 15th-century woodcarving clearly illustrates, the emptying of chamber pots onto the street would have done little to clear the air!

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Slaughterhouse stench -

Slaughterhouses were notorious for their lack of hygiene. The entrails of many a hapless animal usually ended up on the pavement, left to rot and putrefy. The stench would have been sickening.

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Medieval latrine -

Likewise, your typical medieval latrine wasn't much more than a hole in the floor. And before the advent of a decent sewage system, yesterday's dinner would likely be found decorating the cobblestone outside the front door.

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Parisian public latrines -

Curiously in medieval France, public latrines were deliberately left unsanitized, the belief being the pungent aroma of overflowing toilets could shield the public from airborne contagion. Pictured is a public urinal in 19th-century Paris.

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Miasmas -

It's no wonder plague ravaged much of Europe throughout the Middle Ages. So-called plague doctors wore a crude version of protective clothing, with the beak mask holding spices thought to purify air. In fact, these "quacks" advised their patients against breathing in foul odors like those emanating from cesspools, garbage dumps, and animal carcasses. Known as miasmas, these smells were thought to harbor germs—a belief that endured until germ theory became more widely accepted in the late 19th century.

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Sovereign scents -

For the most part, royalty and the nobility were spared the awful sights and bad smells of their realm. The last Tudor monarch, Elizabeth I (1533–1603) reportedly washed her hands in perfumed water before every meal, a luxury afforded the fortunate few.

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Pomanders -

Wealthy individuals carried pomanders, small spherical balls often made of gold or silver and filled with scented material. This one opens out into eight segments, some of which are inscribed with the name of the contents, including rose and musk.

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Gunpowder -

Anyone breathing in 18th-century air would have recognized the unmistakable smell of gunpowder, or rather the crystallization of saltpeter, the principal ingredient in gunpowder. Mills everywhere were producing this chemical explosive, but it was across battlefields in the 19th century where the sulfuric compounds from gunpowder were particularly prevalent, for example at Waterloo.

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Tanning -

Tanning, the process of treating skins and hides of animals to produce leather, was considered such a noxious or "odoriferous trade" that its practice was relegated to the outskirts of towns and cities.

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Industrial Revolution -

One of the biggest environmental impacts of the Industrial Revolution was the number of pollutants it released into the environment. Air quality was lamentable, and the thick, sooty, stench of factory smoke hung over many cities in Great Britain, across Europe, and the United States.

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Poisonous pigments -

Some of the pigments used by history's greatest artists were dangerous to the nose, with a few containing up to 60% arsenic! Pictured is a self-portrait by French painter Édouard Manet (1832–1883).

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A smell of history -

In an interesting experiment, the Institute for Sustainable Heritage at UCL, a London university, has identified the chemical recipe for old book smell—specifically capturing the scent of the library at St Paul's Cathedral in London prior to a renovation that started in 2018, according to a report carried by CNN. The idea is to recreate and archive the historic book smell for future generations. The library is pictured in 1950.

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The real smell of napalm -

Forget the smell of napalm in the morning. Many veterans shudder when recalling its odor, with one describing it as gasoline and laundry detergent, according to Information Today. The United Nations banned napalm usage against civilian targets in 1980.

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Typewriter ribbon -

Some smells recall the odor of items no longer in use, discarded in the wake of new technology. One example is the inky aroma of a fresh typewriter ribbon.

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School dinner -

Smell is a sense very much associated with memory. Our autobiographical memories are filled with vivid smell episodes. Take school meals, for example. The aromas of certain cooked foods can whisk you straight back to childhood and waiting in line to be served.

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Funeral -

More poignantly, the surviving partner of a loved one will often keep an item of clothing left by the departed, their scent the last intimate trace of their being.

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Scent recreations -

Intriguingly, scents are being recreated of disappearing and threatened environments. The New York Times reports of an artist working together with a perfumer in the Netherlands to produce a fragrance based on the smell of a polder, a low-lying tract used for irrigation and dairy farming—a landform that's increasingly being lost to flooding and housing development.

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Odeuropa -

Odeuropa is a European research project that explores olfactory heritage. With the help of new technologies, chemists and archaeologists can examine flavors and smells of the past. To that effect, researchers from different disciplines across the continent have joined forces to create something like an encyclopedia of smells.

Sources: (CNN) (The Guardian) (Smithsonian Magazine) (Information Today) (The New York Times) (Odeuropa)

See also: Sniff out 30 amazing facts about the sense of smell

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