10 Innovations That Led to the Modern Bullet

Gunpowder and dirt hang in the air as the U.S. Army's 1st Cavalry Division horse detachment make their traditional 'cavalry charge' to conclude a March 25, 2009, ceremony at Fort Hood, Texas. Image courtesy U.S. Army (CC By 2.0 license)

The invention of black powder may have been one of humankind's most significant achievements, but it led to a messy battlefield. In a protracted fight, during which soldiers discharged their weapons many times, a thick veil of smoke filled the air, sometimes rendering the enemy invisible. By the 1800s, chemists and inventors were hunting for a better propellant.

The answer came from the plant kingdom, in the form of cellulose. This macromolecule, or long chain of repeating glucose units, is common in plant cells and can be obtained from wood pulp or the short fibers of cotton. In 1846, the Swiss chemist Christian Friedrich Schönbein took cotton and dipped it in a mixture of nitric and sulfuric acids, causing the hydroxyl groups of the cellulose to be replaced by nitro groups. The result was an extremely flammable substance known as nitrocellulose or guncotton. Unfortunately, it tended to decompose spontaneously and explode without warning. Then, in the 1880s, French engineer Paul Vieille found that when nitrocellulose was mixed with certain stabilizers, it became much less volatile. This led directly to a new type of gunpowder, commonly known as smokeless powder, that revolutionized ammunition. Now a soldier could fire his weapon and not disappear behind a plume of white smoke.

The modern form of smokeless powder -- cordite -- contains nitrocellulose, nitroglycerine and petroleum jelly. In its final form, it looks like small, graphite-colored grains.