- Written by Doris Montag Doris Montag
A firework requires three key components — an oxidizer, a fuel, and a chemical mixture — to produce the color. When any element burns, its electrons get excited, and it releases energy in the form of light — in this case, fireworks. But how was this discovered?
The popular legend is that a Chinese cook in the 200 BC accidentally spilled saltpeter, a flavoring salt, into an open fire. It created a powder that, in the cook’s kitchen, made a colored flame. But if it were stuffed into a bamboo tube and left in the hot fire, it exploded with a loud blast.
These early fireworks were thrown into the fire, not blasted into air. The first fireworks produced only a loud bang. This was desirable in religious fireworks because the bang was what frightened the evil spirits away.
During 600-900 AD, Chinese alchemists mixed saltpeter with sulfur and charcoal to discover a crude recipe for gunpowder. The use of gunpowder weaponry was documented in China in 1046 with a reference to a rudimentary gunpowder catapult and gunpowder bombs.
The Smithsonian reports gunpowder weaponry in use during the Crusades (1100-1300 AD). It credits the Crusaders, missionaries, and explorers like Marco Polo with introducing gunpowder into Europe and Arabia in the 13th century.
By the 1500s, inventors had developed cannons and muskets that used gunpowder.
But back to our topic: Fireworks were popular with European rulers for religious festivals and public entertainment. The addition of a fuse allowed for a controlled explosion.
In the 1700s, Italy developed self-propelled aerial shells that shot into the air before exploding with a loud bang and, by this time, an orange flame. The Italians discovered they could mix various chemicals to create colorful fireworks — strontium for red, barium for green, copper for blue, and sodium for yellow.
Circa the 1830s, Italian pyrotechnicians produced the first modern firework by adding trace amounts of metals and other ingredients to enhance the colors and create shapes.
The shells contained fuel in a cone bottom, while the scoop of the cone contained an outer layer of pyrotechnic stars. These tiny balls contained the chemicals needed to produce a desired color. The shell also had an inner bursting charge.
Today, the shape the firework produces is a product of the inner anatomy of the aerial shell.
The firework’s sounds are the result of combining multiple layers of an organic salt with the oxidizer potassium perchlorate. As each layer burns, it slowly releases a gas, creating the whistling sound associated with most firework rockets. Aluminum or iron flakes can create hissing or sizzling sparkles, while titanium powder can create loud blasts.
In America, fireworks were used to celebrate events long before the American Revolutionary War. In 1777, one year after the Declaration of Independence, fireworks became a Fourth of July celebration tradition. In 1789, fireworks were used at George Washington’s inauguration. And, as they say, the rest is history!
Historically, the largest manufacturers of fireworks have been China, Italy, and Germany. Today, China produces and exports more fireworks than any other country in the world, according to History.com.
A word of caution: Fireworks can cause serious health effects in high doses. With each explosion, heavy metals, dioxins, perchlorates, and other air pollutants are released into the atmosphere.
Alternatives to the barium nitrate and oxidizer potassium perchlorate are being developed. The challenge is creating safer alternatives as cheaply as the gunpowder model.
In 2004, Disneyland in California launched fireworks with compressed air rather than gunpowder. Compressed air reduces smoke, fumes, and pollution. Electronic timers were used to explode the shells, thus allowing fireworks to be synchronized with music.
Fireworks without the loud bang were introduced in 2015, providing all the beauty of the sparkle without the loud sounds that traumatize pets, wildlife, and many humans.
Fireworks are often a source of personal injury, with about 65% of those injuries occurring in the 30 days surrounding the Fourth of July. More than 40% of the injuries involve sparklers and rockets.
Enjoy, but be careful out there!
Doris Montag is a homespun historian and an exhibit curator who researches and displays historical collections of ordinary things, such as can openers, crochet, toy sewing machines, hand corn planters, powder compacts, egg cartons, and more. Contact or follow her on Facebook, HistoryofOrdinaryThings.