This article is a history of how explosives developed. It does not give instructions for making any of them, and that is deliberate.
Origins in China
Black powder, the first known chemical explosive, is generally traced to China. Its ingredients are saltpeter (potassium nitrate), sulfur and charcoal. Early Chinese texts from around the ninth century describe mixtures of these substances in warnings about alchemists whose experiments produced fire or burned their hands and workshops. The link to alchemy is real: people searching for elixirs worked with sulfur and saltpeter and noticed what happened when they were heated together. The wider setting is covered in the story of alchemy and the roots of chemistry.
By the eleventh century, military manuals such as the Wujing Zongyao (about 1044) recorded powder formulas for incendiary weapons, smoke and early rockets. In these early uses, the mixture often burned rather than detonating, and was used in fire arrows, bombs and signals before it was used to throw projectiles. The date at which true guns appeared is debated, with surviving metal barrels and depictions from around the thirteenth century.
Spread westward
Knowledge of saltpeter and powder reached the Islamic world and Europe by the thirteenth century, though the route is not fully documented. A text attributed to Roger Bacon around 1267 mentions a flash and bang from a mixture, but its meaning is disputed. The story of a German monk “Berthold Schwarz” inventing the gun is a legend with no firm evidence behind it.
By the fourteenth century, cannon were used in European wars, and they were improved over time. Casting large barrels in bronze, and later iron, depended on foundry skill that came from bell-making, a link to the bronze alloy tradition. Powder-making grew into a trade of its own.
Making and improving black powder
Typical black powder was roughly three-quarters saltpeter by weight, with the remainder split between charcoal and sulfur, though proportions varied with place and period. Saltpeter was the scarce part. It had to be extracted from soil rich in decayed organic matter, such as stable floors, cellars and dovecotes, and states set up collection systems and imported it from India. Supply worries are one reason governments and chemists later welcomed synthetic nitrogen compounds, discussed in the history of industrial chemistry.
Early powder was made as a fine dust, which separated into its ingredients in transport. The introduction of “corning,” pressing the damp mixture into grains and drying it, made powder more consistent, easier to load and less affected by moisture. Water-powered stamping mills later replaced hand mixing. Mills had a serious record of accidental explosions, and the buildings were commonly spaced apart and built with light roofs for that reason.
Black powder also had peaceful uses. It was used in mining and quarrying, canal and road building, and tunneling, and the demand for rock-breaking grew along with steam in mining and the spread of railways. It was also used for fireworks and signals.
Nitrated compounds: a new family
The nineteenth century brought explosives made by treating organic materials with nitric acid, usually mixed with sulfuric acid.
- Guncotton. In 1846, Christian Friedrich Schönbein, a chemist in Basel, produced nitrated cotton. It was powerful but unstable, and several factory explosions in the following years limited its use until stabilization methods improved.
- Nitroglycerin. Ascanio Sobrero in Turin first made it in 1847 and was reportedly alarmed enough by its power to discourage its use. It is a liquid that can detonate from shock, which made handling very dangerous.
- Dynamite. Alfred Nobel, working with his family in Sweden, took up nitroglycerin and was affected by an accident in 1864 that killed his younger brother Emil and others. In 1867, Nobel patented dynamite, in which nitroglycerin was absorbed in a porous earth called kieselguhr, making it far safer to transport and handle. He also developed blasting caps to set off charges reliably.
- TNT. Joseph Wilbrand made trinitrotoluene in 1863 as a dye ingredient. Its stability and low sensitivity made it useful for shells many years later.
Dynamite shaped large engineering projects such as tunnels and canals, since it allowed faster rock work. It also created a lasting moral question about invention, and Nobel’s will established the prizes that carry his name.
Smokeless powder
Black powder produced thick smoke and fouled barrels. In 1884, French chemist Paul Vieille produced a colloidal nitrocellulose powder, often called Poudre B, which burned more cleanly and gave greater power from a smaller charge. Other countries adopted similar propellants soon afterward, including cordite in Britain. Smokeless powders changed how firearms were designed and how battles looked.
A pattern in the history
The history of explosives shows how scientific understanding can lag behind use. Black powder was used for centuries before anyone understood why it burned so vigorously. Later explosives came from a better grasp of how nitrogen-rich compounds release energy rapidly. Each advance was followed by accidents, regulations on storage and transport, and efforts to stabilize new compounds. Outcomes were uncertain along the way, and many early experimenters were injured or killed. It is a story to understand, not a method to follow.