From the late 17th century gunpowder came into use in Cornish mines.
Holes were drilled and then charged with gunpowder and blasted. Although blasting enabled larger quantities of rock to be broken, it was also a risk for those involved. Many miners were injured or killed when charges went off early, or when they returned to re-light fuses, often unreliable and made from goose quills.
Gunpowder was very expensive. It was made by grinding charcoal, sulphur and saltpetre together in ‘incorporating mills’. The process was complex and extremely dangerous. Gunpowder was imported into Cornwall in 1808 when the first Cornish gunpowder factory opened at Cosawes Wood, Perran-ar-Worthal, about 5 miles from Falmouth. The adoption of gunpowder was a great technological breakthrough. In 1836 alone, 30 tonnes of gunpowder were used in Cornish mines. By the 1860s high explosives were being used far more efficiently and had become far more refined.