Sulphur, the 16th element on the periodic table and one of the most abundant elements in Earth's crust, was familiar to mankind even in ancient times. This nonmetallic element has no odour or flavour but has a distinctive yellow colour and amorphous crystalline structure in its most common elemental form. Sulphur has many industrial uses today as it did in ancient times, although those uses have changed.
While sulphur's utility has varied over the millennia, one use spans both ancient and modern times. Black gunpowder requires sulphur as one of its constituents. Sulphur, saltpetre and charcoal made up the earliest versions of gunpowder; Chinese alchemists used this flammable substance in weaponry and in fireworks. Other civilisations used gunpowder almost exclusively as a weapon. By the 15th century, sulphur in the form of gunpowder provided cannons at sea and on land with their explosive force.
To the modern nose, burning sulphur and sulphur compounds has an unpleasant smell. Early alchemists, shamans and priests considered this strong and acrid aroma a potent force for driving away evil spirits or bad air. Roman purifying rituals included fumigating a building or personal belongings with the smoke from burning sulphur. To sweeten the strong scent for more delicate noses, priests might blend sulphur with more pleasant aromatics, such as myrrh or dried herbs.
Although sulphur's ability to ward off evil spirits might be hard to determine, its ability to drive away insects keeps it useful today. Burning sulphur in a home purportedly drives off mice, roaches and other vermin; powdered sulphur sprinkled in the corners of a pantry supposedly keeps the foods stored within safe from foraging creatures. Ticks, fleas and lice dislike sulphur-containing compounds; for ancient people who lacked modern conveniences, such as running water and machine-laundered clothing, sulphur powder provided a way to rid the home of these painful nuisances.
Ancient and medieval medical practitioners made frequent use of sulphur powder taken internally as a vermifuge (deworming agent) and as a means of balancing the body's "humours." As sulphur burns, medieval physicians considered it a choleric element that would neutralise phlegmatic or melancholic illnesses. Humans suffer few ill effects from minor amounts of sulphur, but another common alchemical and medicinal ingredient, quicksilver, did far more damage. Quicksilver, or mercury as modern scientists know it, held as much importance as sulphur to medieval medics. Zosimos of Panoplis averred that "Sulfur is in effect the father and quicksilver in effect the mother" of alchemy and, therefore, of medicine.