Gunpowder

Historians believe gunpowder reached Europe around the 13th century, originating from China and India and was the only explosive known until the 19th century.

Although at first, this product was frowned upon and associated with “black magic”, by the time the Tudors were in power, gunpowder makers had become highly trained and well-regarded by their peers. Records show that gunpowder started being produced at the Tower of London in 1346, and by 1515, the King employed several gunpowder makers on a permanent basis.

The Chemistry

Tudor gunpowder makers were skilled at mixing very carefully the right amounts of charcoal (C), sulphur (S) and saltpetre (potassium nitrate, KNO3) to obtain the best results. The charcoal was traditionally produced from the willow tree, but other trees were also used, including hazel, pine and laurel. Although these early chemists did not know the exact chemical reactions, they knew that charcoal and sulphur acted as fuel and saltpetre was the “trigger” (oxidiser). In fact, the reaction also occurs without potassium nitrate, but it becomes a very slow process, closer to burning wood than explosives. Very quickly, alchemists took advantage of the heat and gas produced in this reaction, and started using gunpowder as a propellant in both fire arms and fireworks.

10 KNO3 + 3 S + 8 C → 2 K2CO3 + 3 K2SO4 + 6 CO2 + 5 N2

A further improvement was the refinement of saltpetre used, by mixing with ashes (containing potassium carbonate, KCO3), resulting in the precipitation of calcium, followed by adding a solution containing alum (potassium aluminium sulfate), blood and turnip slices to generate a colourless solution.

The Invention Of Bullets

A major development in this area was the incorporation of distilled spirits or wine when grinding the ingredients. Initially this was done to reduce the risk of explosion, but other advantages were discovered, including easier storage and more powerful blasts. This paste – referred to as mill cake - was rolled into balls and allowed to dry, and the first bullets were born. Unfortunately, as these were done by hand, there was great variation and results were sometimes unpredictable. To overcome this problem, gunpowder manufacturers started forcing mill cake through sieves to produce gunpowder balls of specific sizes, incredibly more powerful than dry gunpowder.

The principle of wetting ingredients to avoid de-mixing and ensuring accurate concentration is an important principle still valid in the pharmaceutical industry today, ensuring each tablet contains the same concentration. A remnant of Tudor achievements.